Network device level optimizations for latency-sensitive RDMA traffic

Abstract

Described herein is a framework for provisioning customized processing for various classes of traffic. A network device in a communication path between a source host machine and a destination host machine extracts a tag from a packet received by the network device. The packet originates at a source running on the source host machine and is destined for the destination host machine. The tag is set by the source and indicates a first traffic class to be associated with the packet, the first traffic class being selected by the source from a plurality of traffic classes. The network device determines, based on the tag, that the first traffic class corresponds to latency sensitive traffic and processes the packet using one or more settings configured in the network device for processing packets associated with the first traffic class.

Description

[Technical field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims the benefit of the filing date of U.S. Provisional Application No. 63 / 332,851, filed April 20, 2022, and U.S. Nonprovisional Application No. 17 / 935,279, filed September 26, 2022, each of which is incorporated by reference in its entirety for all purposes.

[0002] Field The present disclosure relates to a framework for provisioning customized handling for different classes of RDMA traffic. In particular, the present disclosure relates to parametric optimization performed based on different classes of RDMA traffic. [Background technology]

[0003] background Organizations continue to migrate their business applications and databases to the cloud to reduce the costs of purchasing, updating, and maintaining on-premise hardware and software. High performance computing applications consistently consume all available computing power to achieve a specific outcome or result. Such applications require dedicated network performance, fast storage, high computing power, and large amounts of memory - resources that are in short supply in the virtualized infrastructure that makes up today's commodity clouds.

[0004] Cloud infrastructure service providers offer newer and faster graphical processing units (GPUs) to address the requirements of these applications. In one example, remote direct memory access (RDMA) provides the high throughput and ultra-low latency required for modern data center applications with low CPU overhead. RDMA is deployed using the RDMA over converged Ethernet (RoCE) protocol, which relies on priority-based flow control (PFC) to enable drop-free networks. However, RDMA workloads running on network clusters rarely achieve the desired level of throughput. One reason for this is that the RoCE congestion management protocol running on network clusters is not optimized. The embodiments described herein address these and other issues. Summary of the Invention

[0005] overview The present disclosure generally relates to a framework for provisioning customized processing for different classes of RDMA traffic. In particular, the present disclosure relates to parametric optimization performed based on different classes of RDMA traffic. The RDMA traffic may include latency sensitive RDMA traffic, bandwidth intensive RDMA traffic, and the like. The bandwidth intensive RDMA traffic may also be referred to as bandwidth sensitive RDMA traffic. As an example, a single queue may be utilized for latency sensitive RDMA traffic, while multiple queues may be utilized to optimize network traffic for bandwidth intensive RDMA traffic (i.e., jitter sensitive traffic). In another example, multiple latency sensitive traffic classes may be used to prevent a situation where different types of latency sensitive traffic cause queuing (and thus jitter) with each other. In other words, multiple latency sensitive queues may be utilized to prevent a head of line (HOL) blocking situation. Various embodiments are described herein, including methods, systems, non-transitory computer readable storage media storing programs, codes, or instructions executable by one or more processors, and the like. These example embodiments are mentioned not to limit or define the disclosure, but to provide examples to aid in understanding the disclosure. Additional embodiments are described and further explanations are provided in the detailed description section.

[0006] One embodiment of the present disclosure is directed to a method that includes extracting, by a network device in a communication path between a source host machine and a destination host machine, a tag from a packet received by the network device, where the packet originated at a source executing on the source host machine and has a destination at the destination host machine, the tag indicating a first traffic class set by the source and associated with the packet, the first traffic class being selected from a plurality of traffic classes by the source; determining, based on the tag, that the first traffic class corresponds to latency sensitive traffic; and processing, by the network device, the packet using one or more settings configured at the network device for processing packets associated with the first traffic class.

[0007] Aspects of the present disclosure provide a network device comprising one or more data processors and a non-transitory computer-readable storage medium containing instructions that, when executed on the one or more data processors, cause the one or more data processors to perform some or all of one or more methods disclosed herein.

[0008] Another aspect of the disclosure provides a computer program product, tangibly embodied in a non-transitory machine-readable storage medium, that includes instructions configured to cause one or more data processors to perform some or all of one or more of the methods disclosed herein.

[0009] The foregoing, together with other features and embodiments, will become more apparent when considered in conjunction with the following specification, claims, and accompanying drawings.

[0010] The features, embodiments, and advantages of the present disclosure will be better understood when the following detailed description is read in conjunction with the accompanying drawings. [Brief description of the drawings]

[0011] [Figure 1] FIG. 1 is a high-level diagram of a distributed environment illustrating a virtual cloud network or overlay cloud network hosted by a cloud service provider infrastructure, according to an embodiment. [Diagram 2] FIG. 2 illustrates a simplified architectural diagram of physical components in a physical network within CSPI, according to one embodiment. [Diagram 3] FIG. 2 illustrates an exemplary arrangement within CSPI in which a host machine is connected to multiple network virtualization devices (NVDs), according to one embodiment. [Figure 4] A diagram illustrating connections between host machines and NVDs to achieve I / O virtualization to support multi-tenancy functionality in one embodiment. [Diagram 5] FIG. 2 illustrates a simplified block diagram of a physical network provided by CSPI, according to one embodiment. [Figure 6] FIG. 2 is an exemplary tree diagram illustrating various parameter settings, according to an embodiment. [Figure 7] FIG. 2 is an exemplary tree diagram illustrating various configuration options for differentiated services code point (DSCP) settings, according to an embodiment. [Figure 8] FIG. 1 is a schematic diagram illustrating a mechanism utilized to mark explicit congestion notification (ECN) packets, according to an embodiment. [Figure 9] 1 is a table illustrating different parameter settings for different types of RDMA traffic, according to an embodiment. [Figure 10]FIG. 1 is a schematic diagram of identifying network locations within a cloud infrastructure to which different parameter markings are applied, according to an embodiment; [Figure 11A] 4 is an exemplary flowchart illustrating steps performed in processing a data packet based on a traffic class of the data packet, according to an embodiment. [Figure 11B] 4 is an exemplary flow chart illustrating steps performed in processing data packets belonging to a bandwidth-sensitive type of traffic class, according to an embodiment. [Figure 11C] 4 is an exemplary flow chart illustrating steps performed in processing data packets belonging to a latency sensitive traffic class according to an embodiment. [Figure 11D] 4 is an exemplary flow chart illustrating steps performed in tagging a portion of a header of a data packet, according to an embodiment. [Figure 12] FIG. 1 is a block diagram illustrating one pattern for implementing a cloud infrastructure as a service system, according to at least one embodiment. [Figure 13] FIG. 1 is a block diagram illustrating another pattern for implementing a cloud infrastructure as a service system, according to at least one embodiment. [Figure 14] FIG. 1 is a block diagram illustrating another pattern for implementing a cloud infrastructure as a service system, according to at least one embodiment. [Figure 15] FIG. 1 is a block diagram illustrating another pattern for implementing a cloud infrastructure as a service system, according to at least one embodiment. [Figure 16] FIG. 1 is a block diagram illustrating an exemplary computer system in accordance with at least one embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] Detailed Description In the following description, for purposes of explanation, specific details are set forth in order to provide a thorough understanding of certain embodiments. It will be apparent, however, that various embodiments may be practiced without those specific details. The figures and descriptions are not intended to be limiting. The word "exemplary" is used herein to mean "serving as an example, instance, or illustration." Any embodiment or design described herein as "exemplary" is not necessarily to be construed as preferred or advantageous over other embodiments or designs.

[0013] Example architecture of cloud infrastructure The term cloud services is typically used to refer to services made available on demand (e.g., by a subscription model) by a cloud service provider (CSP) to users or customers using systems and infrastructure (cloud infrastructure) provided by the CSP. Typically, the servers and systems that make up the CSP's infrastructure are separate from the customers' own on-premise servers and systems. Thus, customers can utilize cloud services provided by the CSP without needing to purchase separate hardware and software resources for the services. Cloud services are designed to provide subscribing customers with easy and scalable access to applications and computing resources that do not require the customers to invest in procuring the infrastructure used to provide the services.

[0014] There are multiple cloud service providers offering different types of cloud services. There are different types or models of cloud services, including Software-as-a-Service (SaaS), Platform-as-a-Service (PaaS), Infrastructure-as-a-Service (IaaS), etc.

[0015] A customer may subscribe to one or more cloud services offered by a CSP. A customer may be any entity, such as an individual, an organization, a business, etc. When a customer subscribes or registers for a service offered by a CSP, a tenancy or account is created for that customer. The account then enables the customer to access one or more subscribed cloud resources associated with the account.

[0016] As mentioned earlier, infrastructure as a service (IaaS) is one particular type of cloud computing service. In the IaaS model, the CSP provides infrastructure (called cloud services provider infrastructure or CSPI) that can be used by the customer to build their own customizable network and deploy their resources. Thus, the customer's resources and network are hosted in a distributed environment by the infrastructure provided by the CSP. This differs from traditional computing, where the customer's resources and network are hosted by the infrastructure provided by the customer.

[0017] CSPI may comprise interconnected high performance computing resources including various host machines, memory resources, and network resources that form a physical network, also referred to as a foundation or underlay network. The resources in CSPI may be distributed across one or more data centers that may be geographically distributed across one or more geographic regions. Virtualization software may be executed by these physical resources to provide a virtualized distributed environment. This virtualization creates an overlay network (also known as a software-based network, software-defined network, or virtual network) on top of the physical network. The physical network of CSPI provides an underlying foundation for creating one or more overlay or virtual networks on top of the physical network. The virtual or overlay network may include one or more virtual cloud networks (VCNs). The virtual network is implemented using software virtualization techniques (e.g., hypervisors, network virtualization devices (NVDs) (e.g., smart NICs), top-of-rack (TOR) switches, functions performed by smart TORs that implement one or more functions performed by the NVDs, and other mechanisms) to create a layer of network abstraction that may run on top of the physical network. Virtual networks can take many forms, including peer-to-peer networks, IP networks, etc. Virtual networks are typically either Layer 3 IP networks or Layer 2 VLANs. This method of virtual or overlay networking is often called a virtual Layer 3 network or an overlay Layer 3 network.Examples of protocols developed for virtual networks include IP-in-IP (or Generic Routing Encapsulation (GRE)), Virtual Extensible LAN (VXLAN - IETF RFC 7348), Virtual Private Networks (VPN) (e.g. MPLS Layer 3 Virtual Private Networks (RFC 4364)), VMware's NSX, Generic Network Virtualization Encapsulation (GENEVE), etc.

[0018] In the case of IaaS, the infrastructure provided by the CSP (CSPI) may be configured to provide virtualized computing resources over a public network (e.g., the Internet). In the IaaS model, the cloud computing service provider may host the infrastructure components (e.g., servers, storage devices, network nodes (e.g., hardware), deployment software, platform virtualization (e.g., hypervisor layer), etc.). In some cases, the IaaS provider may provide various services (e.g., billing, monitoring, logging, security, load balancing, and clustering, etc.) to accompany those infrastructure components. Thus, these services may be policy-driven, so that IaaS users may implement policies to drive load balancing to maintain application availability and performance. CSPI provides infrastructure and a set of complementary cloud services that enable customers to build and run a wide range of applications and services within a highly available, hosted, distributed environment. CSPI provides high-performance computing resources and computing power as well as storage capacity within a flexible virtual network that is securely accessible from various networked locations, such as from the customer's on-premise network. When a customer subscribes or registers for an IaaS service offered by a CSP, the tenancy created for that customer is a secure, isolated partition within the CSP where the customer can create, organize, and manage their cloud resources.

[0019] Customers can build their own virtual networks using compute, memory, and network resources provided by CSPI. One or more customer resources or workloads, such as compute instances, can be deployed into these virtual networks. For example, customers can build one or more customizable private virtual networks, called Virtual Cloud Networks (VCNs), using resources provided by CSPI. Customers can deploy one or more customer resources, such as compute instances, into the customer's VCN. Compute instances can take the form of virtual machines, bare metal instances, etc. Thus, CSPI provides infrastructure and a set of complementary cloud services that enable customers to build and run a wide range of applications and services within a highly available hosted virtual environment. Customers do not manage or control the underlying physical resources provided by CSPI, but they do have control over the operating system, storage, deployed applications, and in some cases, limited control over selected network components (e.g., firewalls).

[0020] The CSP may provide a console that allows customers and network administrators to configure, access, and manage resources deployed in the cloud using CSPI resources. In one embodiment, the console provides a web-based user interface that can be used to access and manage the CSPI. In some implementations, the console is a web-based application provided by the CSP.

[0021] CSPI may support single-tenancy or multi-tenancy architectures. In a single-tenancy architecture, a software component (e.g., application, database) or hardware component (e.g., host machine or server) serves a single customer or tenant. In a multi-tenancy architecture, a software component or hardware component serves multiple customers or tenants. Thus, in a multi-tenancy architecture, CSPI resources are shared among multiple customers or tenants. In a multi-tenancy situation, precautions are taken and safeguards are implemented within CSPI to ensure that each tenant's data remains isolated and invisible to other tenants.

[0022] In a physical network, a network endpoint ("endpoint") refers to a computing device or system that is connected to the physical network and communicates with the connected network. A network endpoint in a physical network may be connected to a local area network (LAN), a wide area network (WAN), or other types of physical networks. Examples of traditional endpoints in a physical network include modems, hubs, bridges, switches, routers, and other network devices, physical computers (or host machines), and the like. Each physical device in a physical network has a fixed network address that can be used to communicate with the device. This fixed network address can be a layer 2 address (e.g., a MAC address), a fixed layer 3 address (e.g., an IP address), and the like. In a virtual environment or network, the endpoints can include various virtual endpoints, such as virtual machines hosted by components of the physical network (e.g., hosted by a physical host machine). These endpoints in the virtual network are addressed by overlay addresses, such as overlay layer 2 addresses (e.g., an overlay MAC address) and overlay layer 3 addresses (e.g., an overlay IP address). Network overlays enable flexibility by allowing network administrators to use software management (e.g., by software implementing the virtual network's control plane) to move between overlay addresses associated with network endpoints. Thus, unlike physical networks, in a virtual network, overlay addresses (e.g., overlay IP addresses) may be moved from one endpoint to another using network management software. Because virtual networks are built on top of physical networks, communication between components in a virtual network involves both the virtual network and the underlying physical network.To facilitate such communications, the CSPI components are configured to learn and store mappings that map overlay addresses in the virtual network to actual physical addresses in the underlying network, and vice versa. These mappings are then used to facilitate communications. Customer traffic is encapsulated to facilitate routing within the virtual network.

[0023] Thus, physical addresses (e.g., physical IP addresses) are associated with components in a physical network, and overlay addresses (e.g., overlay IP addresses) are associated with entities in a virtual network. Both physical and overlay IP addresses are types of real IP addresses. They are distinct from virtual IP addresses, which are mapped to multiple real IP addresses. Virtual IP addresses provide a one-to-many mapping between a virtual IP address and multiple real IP addresses.

[0024] A cloud infrastructure or CSPI is physically hosted in one or more data centers in one or more regions around the world. The CSPI may include components in a physical or foundational network and virtual components (e.g., virtual networks, compute instances, virtual machines, etc.) in a virtual network built on top of the components of the physical network. In an embodiment, the CSPI is organized and hosted in realms, regions, and availability domains. A region is a localized geographic area that typically includes one or more data centers. Regions are generally independent of each other and may be separated by vast distances, for example, across multiple countries or continents. For example, a first region may be in Australia, another region may be in Japan, yet another region may be in India, etc. CSPI resources are divided between regions such that each region includes its own independent subset of CSPI resources. Each region may provide a set of core infrastructure services and resources, such as compute resources (e.g., bare metal servers, virtual machines, containers, and related infrastructure), storage resources (e.g., block volume storage, file storage, object storage, archival storage), network resources (e.g., virtual cloud networks (VCNs), load balancing resources, connections to on-premises networks), database resources, edge network resources (e.g., DNS), and access management and monitoring resources. Each region typically has multiple paths connecting it to other regions in the realm.

[0025] Because using nearby resources is faster than using resources that are farther away, applications are typically deployed in the region (i.e., deployed to the infrastructure associated with that region) where the application is most frequently used. Applications may also be deployed in different regions for a variety of reasons, such as redundancy to reduce the risk of region-wide events such as major weather systems or earthquakes, to meet changing requirements for legal jurisdictions, tax areas, and other business or social criteria.

[0026] Data centers within a region may be further organized and subdivided into availability domains (AD). An availability domain may correspond to one or more data centers located within a region. A region may be composed of one or more availability domains. In such a distributed environment, CSPI resources are specific to a region, such as a virtual cloud network (VCN), or specific to an availability domain, such as a compute instance.

[0027] The ADs in a region are configured to be isolated from each other, fault tolerant, and highly unlikely to fail simultaneously. This is achieved by the ADs not sharing critical infrastructure resources such as networks, physical cables, cable paths, cable entry points, etc., such that a failure in one AD in a region is unlikely to affect the availability of other ADs in the same region. ADs in the same region may be connected to each other by low-latency, high-bandwidth networks that provide high availability connectivity to other networks (e.g., the Internet, customer on-premises networks, etc.), as well as allowing for the creation of replicated systems in multiple ADs for both high availability and disaster recovery. Cloud services use multiple ADs to ensure high availability and protect against resource failures. As the infrastructure provided by the IaaS provider grows, more regions and ADs with additional capacity may be added. Traffic between availability domains is typically encrypted.

[0028] In an embodiment, regions are grouped into realms. A realm is a logical collection of regions. Realms are isolated from each other and do not share any data. Regions in the same realm may communicate with each other, but regions in different realms cannot communicate. A customer's tenancy or account, along with a CSP, exists in a single realm and can be distributed across one or more regions that belong to that realm. Typically, when a customer subscribes to an IaaS service, a tenancy or account is created for the customer in a region designated by the customer in a realm (called the "home" region). The customer can extend the customer's tenancy across one or more other regions in the realm. The customer cannot access regions that are not in the realm in which the customer's tenancy resides.

[0029] An IaaS provider may offer multiple realms, each catering to a particular set of customer or user requirements. For example, a commercial realm may be offered to commercial customers. As another example, a realm may be offered to a particular country for customers in that country. As yet another example, a government realm may be offered to a government, etc. For example, the government realm may cater to a particular government requirement and may have a higher level of security than the commercial realm. For example, Oracle Cloud Infrastructure (OCI) currently offers a realm for a commercial region and two realms for a government cloud region (e.g., FedRAMP certified and IL5 certified).

[0030] In an embodiment, an AD may be subdivided into one or more failure domains. A failure domain is a group of infrastructure resources within an AD to provide anti-affinity. Fault domains allow for distribution of compute instances so that multiple compute instances are not on the same physical hardware within a single AD. This distribution is known as anti-affinity. A failure domain refers to a set of hardware components (computers, switches, etc.) that share a single point of failure. A compute pool is logically divided into failure domains. Thus, a hardware failure or compute hardware maintenance event that affects one failure domain does not affect instances in other failure domains. Depending on the embodiment, the number of failure domains per AD may vary. For example, in an embodiment, each AD includes three failure domains. Fault domains act as logical data centers within an AD.

[0031] When a customer subscribes to an IaaS service, resources from CSPI are provisioned for the customer and associated with the customer's tenancy. The customer can use these provisioned resources to build private networks and deploy resources into these networks. A customer's network hosted in the cloud by CSPI is called a Virtual Cloud Network (VCN). A customer can set up one or more Virtual Cloud Networks (VCNs) using the CSPI resources allocated to the customer. A VCN is a Virtual Private Network or a Software-Defined Private Network. The customer's resources deployed in the customer's VCN can include compute instances (e.g., virtual machines, bare metal instances) and other resources. These compute instances may represent various customer workloads, such as applications, load balancers, databases, etc. The compute instances deployed in the VCN can communicate with publicly accessible endpoints ("public endpoints") over a public network such as the Internet, with other instances in the same VCN or other VCNs (e.g., other VCNs of the customer or VCNs not belonging to the customer), with the customer's on-premises data center or network, and with service endpoints and other types of endpoints.

[0032] CSPs may offer various services using CSPI. In some cases, customers of CSPI themselves may act as service providers and offer services using CSPI resources. Service providers may expose service endpoints characterized by identifying information (e.g., IP addresses, DNS names, and DNS ports). Customer resources (e.g., compute instances) can consume a particular service by accessing the service endpoints exposed by the service for that particular service. These service endpoints are generally endpoints that are publicly accessible by users over a public communications network, such as the Internet, using a public IP address associated with the endpoint. Publicly accessible network endpoints are sometimes referred to as public endpoints.

[0033] In one embodiment, a service provider may expose a service via an endpoint for the service (sometimes referred to as a service endpoint). Customers of the service can then access the service using this service endpoint. In some implementations, a service endpoint provided for a service may be accessed by multiple customers wishing to consume the service. In other implementations, a dedicated service endpoint may be provided to a customer, allowing only that customer to access the service using that dedicated service endpoint.

[0034] In an embodiment, when a VCN is created, it is associated with a private overlay Classless Inter-Domain Routing (CIDR) address space, which is a range of private overlay IP addresses (e.g., 10.0 / 16) that are assigned to the VCN. A VCN includes associated subnets, route tables, and gateways. A VCN exists within a single region but can span one or more or all of the region's availability domains. A gateway is a virtual interface configured for a VCN that enables traffic to and from the VCN to one or more endpoints outside the VCN. One or more different types of gateways may be configured for a VCN to enable communication to and from different types of endpoints.

[0035] A VCN may be subdivided into one or more subnetworks, such as one or more subnets. A subnet is thus a unit of configuration or subdivision that may be created within a VCN. A VCN may contain one or more subnets. Each subnet in a VCN is associated with a contiguous range of overlay IP addresses (e.g., 10.0.0.0 / 24 and 10.0.1.0 / 24) that represents a subset of address space within the VCN's address space that does not overlap with other subnets in that VCN.

[0036] Each compute instance is associated with a virtual network interface card (VNIC) that allows the compute instance to participate in a subnet of a VCN. A VNIC is a logical representation of a physical network interface card (NIC). In general, a VNIC is an interface between an entity (e.g., compute instance, service) and a virtual network. A VNIC resides in a subnet and has one or more associated IP addresses and associated security rules or policies. A VNIC is equivalent to a layer 2 port on a switch. A VNIC is connected to a compute instance and is connected to a subnet in a VCN. A VNIC associated with a compute instance allows the compute instance to be part of a subnet of a VCN and allows the compute instance to communicate (e.g., send and receive packets) with endpoints on the same subnet as the compute instance, with endpoints in a different subnet in the VCN, or with endpoints outside the VCN. Thus, a VNIC associated with a compute instance determines how the compute instance connects with endpoints inside and outside the VCN. A VNIC for a compute instance is created and associated with the compute instance when the compute instance is created and added to a subnet in a VCN. For a subnet that contains a set of compute instances, the subnet contains VNICs that correspond to the set of compute instances, and each VNIC connects to one compute instance in the set of compute instances.

[0037] Each compute instance is assigned a private overlay IP address through the VNIC associated with the compute instance. This private overlay IP address is assigned to the VNIC associated with the compute instance when the compute instance is created and is used to route traffic to and from the compute instance. All VNICs within a particular subnet use the same route table, security lists, and DHCP options. As previously mentioned, each subnet in a VCN is associated with a contiguous range of overlay IP addresses (e.g., 10.0.0.0 / 24 and 10.0.1.0 / 24) that represents a subset of address space within the VCN's address space that does not overlap with other subnets in that VCN. For a VNIC on a particular subnet of a VCN, the private overlay IP address assigned to the VNIC is an address from the contiguous range of overlay IP addresses assigned to this subnet.

[0038] In an embodiment, a compute instance may be optionally assigned additional overlay IP addresses, such as one or more public IP addresses if in a public subnet, in addition to the private overlay IP address. These multiple addresses may be assigned to the same VNIC or across multiple VNICs associated with the compute instance. However, each instance has a primary VNIC that is created during instance launch and associated with the private overlay IP address assigned to the instance, and this primary VNIC cannot be removed. Additional VNICs, called secondary VNICs, may be added to an existing instance in the same availability domain as the primary VNIC. All VNICs are in the same availability domain as the instance. The secondary VNICs can be in a subnet in the same VCN as the primary VNIC, or in a different subnet, either in the same VCN or in a different VCN.

[0039] If a compute instance is in a public subnet, the compute instance may optionally be assigned a public IP address. When a subnet is created, it can be specified as either a public subnet or a private subnet. A private subnet means that resources in the subnet (e.g., compute instances) and associated VNICs cannot have public overlay IP addresses. A public subnet means that resources in the subnet and associated VNICs can have public IP addresses. Customers can specify a subnet to exist in a single availability domain or across multiple availability domains within a region or realm.

[0040] As mentioned above, a VCN may be subdivided into one or more subnets. In one embodiment, a Virtual Router (VR) configured for a VCN (referred to as a VCN VR or simply VR) enables communication between subnets of the VCN. For a subnet in a VCN, the VR represents a logical gateway for that subnet, allowing the subnet (i.e., the compute instances on that subnet) to communicate with endpoints on other subnets in the VCN and with other endpoints outside the VCN. A VCN VR is a logical entity configured to route traffic between VNICs in a VCN and a virtual gateway ("gateway") associated with the VCN. Gateways are further described below with respect to FIG. 1. A VCN VR is a Layer 3 / IP layer concept. In one embodiment, there is one VCN VR for a VCN, which may have an unlimited number of ports addressed by IP addresses, one port for each subnet of the VCN. In this way, a VCN VR has a different IP address for each subnet in the VCN to which the VCN VR is connected. The VRs are also connected to various gateways configured for the VCN. In one embodiment, a particular overlay IP address from a subnet's overlay IP address range is reserved for the ports of the VCN VR of that subnet. For example, consider a VCN that includes two subnets with associated address ranges 10.0 / 16 and 10.1 / 16, respectively. For the first subnet in the VCN with address range 10.0 / 16, an address from this range is reserved for the ports of the VCN VR of that subnet. In some cases, the first IP address from this range may be reserved for a VCN VR. For example, for a subnet with overlay IP address range 10.0 / 16, IP address 10.0.0.1 may be reserved for the ports of the VCN VR of that subnet.For a second subnet in the same VCN with address range 10.1 / 16, the VCN VR may have a port in that second subnet with IP address 10.1.0.1. The VCN VR has a different IP address for each of the subnets in the VCN.

[0041] In some other embodiments, each subnet in a VCN may include a VR associated with it that is addressable by the subnet using a reserved or default IP address associated with the VR. The reserved or default IP address may be, for example, the first IP address from a range of IP addresses associated with the subnet. VNICs in a subnet can use this default or reserved IP address to communicate (e.g., send and receive packets) with the VR associated with the subnet. In such embodiments, a VR is an ingress / egress point for that subnet. VRs associated with a subnet in a VCN can communicate with other VRs associated with other subnets in the VCN. VRs can also communicate with gateways associated with the VCN. The VR functions of a subnet are running on or performed by one or more NVDs that are running the VNIC functions of the VNICs in the subnet.

[0042] Route tables, security rules, and DHCP options may be configured for a VCN. A route table is a virtual route table for a VCN and contains rules for routing traffic from subnets in the VCN to destinations outside the VCN via gateways or specially configured instances. A VCN's route table can be customized to control how packets are forwarded / routed to and from the VCN. DHCP options refer to configuration information that is automatically provided to an instance when the instance launches.

[0043] Security rules configured for a VCN represent the overlay firewall rules for the VCN. Security rules include ingress and egress rules and can specify the type of traffic (e.g., based on protocol and port) that is allowed in and out of instances in the VCN. Customers can choose whether a particular rule is stateful or stateless. For example, a customer can allow inbound SSH traffic from any location to a set of instances by configuring a stateful ingress rule with source CIDR 0.0.0.0 / 0 and destination TCP port 22. Security rules can be implemented using network security groups or security lists. A network security group consists of a set of security rules that apply only to resources in that group. A security list, on the other hand, contains rules that apply to all resources in any subnet that uses the security list. A VCN may include a default security list that contains the default security rules. DHCP options configured for a VCN provide configuration information that is automatically provided to instances in the VCN when the instances launch.

[0044] In one embodiment, configuration information for a VCN is determined and stored by a VCN control plane. The configuration information for a VCN may include, for example, information about address ranges associated with the VCN, subnets and associated information within the VCN, one or more VRs associated with the VCN, compute instances and associated VNICs within the VCN, NVDs performing various virtualized network functions associated with the VCN (e.g., VNICs, VRs, gateways), state information for the VCN, and other VCN-related information. In one embodiment, a VCN distribution service publishes the configuration information stored by the VCN control plane or a portion thereof to the NVD. The distributed information may be used to update information (e.g., forwarding tables, routing tables, etc.) stored and used by the NVD to forward packets to and from compute instances in the VCN.

[0045] In one embodiment, the creation of VCNs and subnets is handled by a VCN Control Plane (CP), and the launch of compute instances is handled by the compute control plane. The compute control plane is responsible for allocating physical resources to compute instances and then calling the VCN control plane to create and connect VNICs to compute instances. The VCN CP also sends VCN data mappings to the VCN data plane, which is configured to perform packet forwarding and routing functions. In one embodiment, the VCN CP provides a distribution service that is responsible for providing updates to the VCN data plane. Examples of the VCN control plane are also shown in Figures 12, 13, 14, and 15 (see reference numbers 1216, 1316, 1416, and 1516) and are described below.

[0046] A customer may create one or more VCNs using resources hosted by CSPI. Compute instances deployed in a customer's VCN may communicate with various endpoints. These endpoints may include endpoints hosted by CSPI and endpoints outside of CSPI.

[0047] A variety of different architectures for implementing cloud-based services using CSPI are shown in Figures 1, 2, 3, 4, 5, 12, 13, 14, and 15 and described below. Figure 1 is a high-level diagram of a distributed environment 100 illustrating an overlay VCN or customer VCN hosted by CSPI according to an embodiment. The distributed environment shown in Figure 1 includes multiple components in an overlay network. The distributed environment 100 shown in Figure 1 is merely an example and is not intended to unduly limit the scope of the claimed embodiments. Many variations, alternatives, and modifications are possible. For example, in some implementations, the distributed environment shown in Figure 1 may include more or fewer systems or components than those shown in Figure 1, may combine two or more subsystems, or may include a different configuration or arrangement of systems.

[0048] As shown in the example depicted in FIG. 1, distributed environment 100 includes CSPI 101, which provides services and resources that customers can subscribe to and use to build their own virtual cloud networks (VCNs). In one embodiment, CSPI 101 provides IaaS services to subscribing customers. Data centers within CSPI 101 may be organized into one or more regions. One exemplary region, “Region US” 102, is shown in FIG. 1. A customer configures a customer’s VCN 104 with respect to the region 102. A customer may deploy various compute instances into VCN 104, which may include virtual machines or bare metal instances. Example instances include applications, databases, load balancers, etc.

[0049] In the embodiment shown in FIG. 1, customer's VCN 104 includes two subnets, "Subnet 1" and "Subnet 2," each with its own CIDR IP address range. In FIG. 1, the overlay IP address range of Subnet 1 is 10.0 / 16, and the address range of Subnet 2 is 10.1 / 16. VCN virtual router 105 represents the logical gateway of the VCN, enabling communication between the subnets of VCN 104 and with other endpoints outside the VCN. VCN VR 105 is configured to route traffic between VNICs in VCN 104 and the gateway associated with VCN 104. VCN VR 105 provides a port for each subnet of VCN 104. For example, VR 105 may provide a port with IP address 10.0.0.1 for Subnet 1 and a port with IP address 10.1.0.1 for Subnet 2.

[0050] Multiple compute instances may be deployed in each subnet, and the compute instances can be virtual machine instances and / or bare metal instances. The compute instances in a subnet may be hosted by one or more host machines in CSPI101. The compute instances join the subnet through the VNIC associated with the compute instance. For example, as shown in FIG. 1, compute instance C1 becomes part of subnet 1 through the VNIC associated with the compute instance. Similarly, compute instance C2 becomes part of subnet 1 through the VNIC associated with C2. In a similar manner, multiple compute instances, which may be virtual machine instances or bare metal instances, may become part of subnet 1. Each compute instance is assigned a private overlay IP address and a MAC address through its associated VNIC. For example, in FIG. 1, compute instance C1 has an overlay IP address of 10.0.0.2 and a MAC address of M1, while compute instance C2 has a private overlay IP address of 10.0.0.3 and a MAC address of M2. Each compute instance in Subnet1, including compute instances C1 and C2, has a default route to VCN VR105 using IP address 10.0.0.1, which is the IP address of a port in VCN VR105 in Subnet1.

[0051] Multiple compute instances, including virtual machine instances and / or bare metal instances, may be deployed in Subnet 2. For example, as shown in FIG. 1, compute instances D1 and D2 become part of Subnet 2 via VNICs associated with the respective compute instances. In the embodiment shown in FIG. 1, compute instance D1 has an overlay IP address of 10.1.0.2 and a MAC address of MM1, while compute instance D2 has a private overlay IP address of 10.1.0.3 and a MAC address of MM2. Each compute instance in Subnet 2, including compute instances D1 and D2, has a default route to VCN VR105 using IP address 10.1.0.1, which is the IP address of a port in VCN VR105 in Subnet 2.

[0052] VCN A 104 may include one or more load balancers. For example, a load balancer may be provided to a subnet and configured to load balance traffic across multiple compute instances on the subnet. A load balancer may be provided to load balance traffic across multiple subnets in a VCN.

[0053] A particular compute instance deployed in VCN 104 may communicate with various endpoints. These endpoints may include endpoints hosted by CSPI 200 and endpoints outside CSPI 200. Endpoints hosted by CSPI 101 may include endpoints on the same subnet as the particular compute instance (e.g., communication between two compute instances in subnet 1), endpoints on a different subnet but within the same VCN (e.g., communication between a compute instance in subnet 1 and a compute instance in subnet 2), endpoints in a different VCN in the same region (e.g., communication between a compute instance in subnet 1 and an endpoint in a VCN in the same region 106 or 110, communication between a compute instance in subnet 1 and an endpoint in a service network 110 in the same region), or endpoints in a VCN in a different region (e.g., communication between a compute instance in subnet 1 and an endpoint in a VCN in a different region 108). Compute instances in a subnet hosted by CSPI 101 may communicate with endpoints not hosted by CSPI 101 (i.e., outside CSPI 101). These external endpoints include endpoints within the customer's on-premise network 116, endpoints within other remote cloud-hosted networks 118, public endpoints 114 accessible via public networks such as the Internet, and other endpoints.

[0054] Communication between compute instances on the same subnet is facilitated using VNICs associated with the source and destination compute instances. For example, compute instance C1 in subnet 1 may want to send a packet to compute instance C2 in subnet 1. For a packet originating from a source compute instance and destined for another compute instance in the same subnet, the packet is first processed by the VNIC associated with the source compute instance. The processing performed by the VNIC associated with the source compute instance may include determining the packet's destination information from the packet header, identifying any policies (e.g., security lists) configured for the VNIC associated with the source compute instance, determining the packet's next hop, performing any packet encapsulation / decapsulation functions as necessary, and then forwarding / routing the packet to the next hop for the purpose of facilitating communication of the packet with its intended destination. If the destination compute instance is in the same subnet as the source compute instance, the VNIC associated with the source compute instance is configured to identify the VNIC associated with the destination compute instance and forward the packet to that VNIC for processing. The VNIC associated with the destination compute instance is then executed to forward the packet to the destination compute instance.

[0055] For packets traveling from a compute instance in a subnet to an endpoint in a different subnet in the same VCN, this communication is facilitated by the VNICs associated with the source and destination compute instances as well as the VCN VRs. For example, if compute instance C1 in subnet 1 of FIG. 1 wants to send a packet to compute instance D1 in subnet 2, the packet is first processed by the VNIC associated with compute instance C1. The VNIC associated with compute instance C1 is configured to route the packet to VCN VR105 using the VCN VR's default route or port 10.0.0.1. VCN VR105 is configured to route the packet to subnet 2 using port 10.1.0.1. The packet is then received and processed by the VNIC associated with D1, which forwards the packet to compute instance D1.

[0056] For packets traveling from a compute instance in VCN 104 to an endpoint outside VCN 104, the communication is facilitated by a VNIC associated with the source compute instance, VCN VR 105, and a gateway associated with VCN 104. One or more types of gateways may be associated with VCN 104. A gateway is an interface between a VCN and another endpoint, the other endpoint being outside the VCN. A gateway is a Layer 3 / IP layer concept that allows a VCN to communicate with endpoints outside the VCN. Thus, a gateway facilitates traffic flow between a VCN and other VCNs or networks. Different types of gateways may be configured for a VCN to facilitate different types of communication with different types of endpoints. Depending on the gateway, the communication may go over a public network (e.g., the Internet) or over a private network. Different communication protocols may be used for these communications.

[0057] For example, compute instance C1 may wish to communicate with an endpoint outside VCN 104. The packet may first be processed by a VNIC associated with the source compute instance C1. This VNIC processing determines that the packet's destination is outside of Subnet 1 of C1. The VNIC associated with C1 may forward the packet to VCN VR 105 of VCN 104. VCN VR 105 then processes the packet and, as part of this processing, determines a particular gateway associated with VCN 104 as the packet's next hop based on the packet's destination. VCN VR 105 may then forward the packet to the particular identified gateway. For example, if the destination is an endpoint within a customer's on-premise network, VCN VR 105 may forward the packet to a Dynamic Routing Gateway (DRG) gateway 122 configured for VCN 104. The packet may then be forwarded from the gateway to the next hop to facilitate propagation of the packet to its ultimate intended destination.

[0058] Various types of gateways may be configured for a VCN. Examples of gateways that may be configured for a VCN are shown in FIG. 1 and described below. Examples of gateways associated with a VCN are also shown in FIG. 12, FIG. 13, FIG. 14, and FIG. 15 (e.g., gateways referenced by reference numbers 1234, 1236, 1238, 1334, 1336, 1338, 1434, 1436, 1438, 1534, 1536, and 1538) and described below. As shown in the embodiment shown in FIG. 1, a dynamic routing gateway (DRG) 122 may be added to or associated with a customer's VCN 104 to provide a path for private network traffic communication between the customer's VCN 104 and another endpoint, which may be the customer's on-premise network 116, a VCN 108 in a different region of the CSPI 101, or another remote cloud network 118 not hosted by the CSPI 101. The customer on-premise network 116 may be a customer network or a customer data center built using the customer's resources. Access to the customer on-premise network 116 is usually highly restricted. For a customer that has both a customer on-premise network 116 and one or more VCNs 104 deployed or hosted in the cloud by CSPI 101, the customer may want the customer on-premise network 116 and the customer cloud-based VCN 104 to be able to communicate with each other. This allows the customer to build an extended hybrid environment that encompasses the customer's VCNs 104 hosted by CSPI 101 and the customer on-premise network 116. The DRG 122 enables this communication. To enable such communication, a communication channel 124 is set up, one endpoint of which is in the customer on-premise network 116 and the other endpoint is in CSPI 101 and connected to the customer's VCN 104. The communication channel 124 may traverse a public or private communication network, such as the Internet.Various communication protocols may be used, such as IPsec VPN technology over a public communication network such as the Internet, Oracle's FastConnect technology using a private network instead of a public network, etc. A device or equipment in the customer's on-premise network 116 that forms one endpoint of the communication channel 124 is called customer premise equipment (CPE), such as CPE 126 shown in Figure 1. On the CSPI 101 side, the endpoint may be a host machine running DRG 122.

[0059] In an embodiment, a Remote Peering Connection (RPC) may be added to the DRG, allowing a customer to peer one VCN with another VCN in a different region. Using such an RPC, the customer's VCN 104 can connect with a VCN 108 in another region using the DRG 122. The DRG 122 may be used to communicate with other remote cloud networks 118 not hosted by the CSPI 101, such as the Microsoft Azure cloud, the Amazon AWS cloud, etc.

[0060] As shown in Figure 1, an Internet Gateway (IGW) 120 may be configured for a customer's VCN 104 that allows compute instances on VCN 104 to communicate with public endpoints 114 accessible over a public network, such as the Internet. The IGW 120 is a gateway that connects a VCN to a public network, such as the Internet. The IGW 120 enables direct access for public subnets in a VCN, such as VCN 104 (resources in the public subnet have public overlay IP addresses) to public endpoints 112 on a public network 114, such as the Internet. Using the IGW 120, connections may be initiated from subnets in VCN 104 or from the Internet.

[0061] A Network Address Translation (NAT) gateway 128 is configured for customer VCN 104 to enable access to the Internet for cloud resources in the customer's VCN that do not have dedicated public overlay IP addresses, without exposing those resources to direct incoming Internet connections (e.g., L4-L7 connections). This allows private subnets in a VCN, such as private subnet 1 in VCN 104, to private endpoints on the Internet. The NAT gateway only allows connections to be initiated from the private subnet to the public Internet, and connections cannot be initiated from the Internet to the private subnet.

[0062] In one embodiment, a Service Gateway (SGW) 126 can be configured for a customer's VCN 104 and provides a path for private network traffic between the VCN 104 and supported service endpoints in the service network 110. In one embodiment, the service network 110 can be provided by a CSP and can provide a variety of services. An example of such a service network is Oracle's Services Network, which provides a variety of services that can be used by a customer. For example, a compute instance (e.g., a database system) in a private subnet of a customer's VCN 104 can back up data to a service endpoint (e.g., object storage) without needing a public IP address or access to the Internet. In one embodiment, a VCN can include only one SGW, and connections can be initiated only from subnets in the VCN, not from the service network 110. When a VCN is peered with another VCN, resources in the other VCN typically do not have access to the SGW. Resources in an on-premises network connected to a VCN using a FastConnect or VPN connection can also use a service gateway configured for that VCN.

[0063] In one implementation, SGW 126 uses the concept of a service Classless Inter-Domain Routing (CIDR) label, which is a string that represents the public IP address range of all regions for a service or group of services of interest. A customer uses the service CIDR label when configuring the SGW and associated route rules to control traffic to the service. A customer can optionally utilize the service CIDR label when configuring security rules, without having to adjust those security rules if the service's public IP address changes in the future.

[0064] A Local Peering Gateway (LPG) 132 is a gateway that can be added to a customer's VCN 104, allowing the VCN 104 to peer with another VCN in the same region. Peering means that the VCNs communicate using private IP addresses without the traffic traversing a public network such as the Internet or routing the traffic through the customer's on-premises network 116. In a preferred embodiment, a VCN includes a separate LPG for each peering it establishes. Local peering or VCN peering is a common method used to establish network connectivity between different applications or infrastructure management functions.

[0065] A service provider, such as a provider of services in service network 110, may provide access to the services using various access models. According to a public access model, the service may be exposed as a public endpoint, which may be publicly accessible by compute instances in the customer's VCN over a public network such as the Internet, and / or privately accessible through SGW 126. According to a particular private access model, the service is made accessible as a private IP endpoint in a private subnet in the customer's VCN. This access is called Private Endpoint (PE) access and allows the service provider to expose the service as an instance in the customer's private network. A private endpoint resource represents a service in the customer's VCN. Each PE appears as a VNIC (called a PE-VNIC with one or more private IPs) in a customer-selected subnet in the customer's VCN. Thus, the PE provides a way to present a service in a subnet of the private customer's VCN using a VNIC. Because the endpoint is exposed as a VNIC, all the features associated with the VNIC, such as routing rules, security lists, etc., are available to the PE VNIC.

[0066] A service provider can register a service to make it accessible through the PE. The provider can associate a policy with the service that limits the visibility of the service to the customer's tenancy. The provider can register multiple services under a single virtual IP address (VIP), especially in the case of multi-tenant services. There can be multiple such private endpoints (in multiple VCNs) representing the same service.

[0067] Compute instances in the private subnet can then access the service using the private IP address of the PE VNIC or the DNS name of the service. Compute instances in the customer's VCN can access the service by sending traffic to the private IP address of the PE in the customer's VCN. A Private Access Gateway (PAGW) 130 is a gateway resource that can be connected to a service provider's VCN (e.g., a VCN in service network 110) and serves as an ingress / egress point for all traffic to and from the private endpoints of the customer's subnet. The PAGW 130 allows the provider to scale the number of PE connections without utilizing internal IP address resources. The provider needs to configure only one PAGW for any number of services registered in a single VCN. The provider can represent the services as private endpoints in multiple VCNs for one or more customers. From the customer's perspective, the PE VNIC appears to be connected to the service the customer wants to interact with instead of being connected to the customer's instance. Traffic going to the private endpoint is routed to the service through the PAGW 130. These are called customer-to-service private connections (C2S (customer-to-service) connections).

[0068] The PE concept can also be used to extend the private access of a service to a customer's on-premises network and data center by allowing traffic to flow through a FastConnect / IPsec link and a private endpoint in the customer's VCN. The private access of a service can also be extended to a customer's peered VCN by allowing traffic to flow between LPG 132 and a PE in the customer's VCN.

[0069] A customer can control routing within a VCN at the subnet level, so that the customer can specify which subnets within a customer's VCN, such as VCN 104, use each gateway. A VCN's route table is used to determine whether traffic is allowed to exit the VCN through a particular gateway. For example, in a particular example, a route table for a public subnet in a customer's VCN 104 may send non-local traffic through IGW 120. A route table for a private subnet in the same customer's VCN 104 may send traffic going to a CSP service through SGW 126. All remaining traffic may be sent through NAT gateway 128. The route table controls only traffic that exits the VCN.

[0070] Security lists associated with a VCN are used to control traffic entering the VCN through a gateway via an inbound connection. All resources within a subnet use the same route table and security lists. Security lists may be used to control the specific types of traffic allowed into and out of instances within a subnet of a VCN. Security list rules may include ingress (inbound) rules and egress (outbound) rules. For example, an ingress rule may specify an allowed source address range, while an egress rule may specify an allowed destination address range. Security rules may specify a specific protocol (e.g., TCP, ICMP), a specific port (e.g., 22 for SSH, 3389 for Windows RDP), etc. In some implementations, the instance's operating system may enforce its own firewall rules that match the security list rules. Rules may be stateful (e.g., connections are tracked and responses are automatically allowed without the use of explicit security list rules for the response traffic) or stateless.

[0071] Access from a customer's VCN (i.e., by resources or compute instances deployed in VCN 104) may be categorized as public access, private access, or dedicated access. Public access refers to an access model in which public IP addresses or NATs are used to access public endpoints. Private access allows customer workloads (e.g., resources in private subnets) in VCN 104 with private IP addresses to access services without traversing a public network such as the Internet. In one embodiment, CSPI 101 allows workloads in a customer's VCN with private IP addresses to access (public service endpoints of) services using a service gateway. Thus, the service gateway provides a private access model by establishing a virtual link between the customer's VCN and the public endpoints of the services that reside outside the customer's private network.

[0072] Additionally, CSPI may provide dedicated public access using technologies such as FastConnect public peering, where a customer's on-premises instances can use a FastConnect connection to access one or more services in the customer's VCN without traversing a public network such as the Internet. CSPI may provide dedicated private access using FastConnect private peering, where a customer's on-premises instances with private IP addresses can use a FastConnect connection to access workloads in the customer's VCN. FastConnect is a network connection alternative to using the public Internet to connect a customer's on-premises network to CSPI and its services. FastConnect provides an easy, resilient, and economical way to create dedicated private connections with higher bandwidth options and a more reliable and consistent network experience when compared to Internet-based connections.

[0073] FIG. 1 and the accompanying description above describe various virtual components in an exemplary virtual network. As previously mentioned, a virtual network is built on an underlying physical network or infrastructure network. FIG. 2 illustrates a simplified architecture diagram of physical components in an underlying physical network in CSPI 200 for a virtual network, according to an embodiment. As shown in the figure, CSPI 200 provides a distributed environment including components and resources (e.g., compute resources, memory resources, and network resources) provided by a cloud service provider (CSP). These components and resources are used to provide cloud services (e.g., IaaS services) to subscribing customers, i.e., customers who subscribe to one or more services provided by the CSP. Based on the services to which the customer subscribes, a subset of the resources (e.g., compute resources, memory resources, and network resources) of CSPI 200 is provisioned for the customer. The customer can then build their own cloud-based (i.e., CSPI-hosted) customizable private virtual network using the physical compute resources, memory resources, and network resources provided by CSPI 200. As previously indicated, these customer networks are referred to as Virtual Cloud Networks (VCNs). Customers can deploy one or more customer resources, such as compute instances, into these customer VCNs. The compute instances can be in the form of virtual machines, bare metal instances, etc. CSPI 200 provides infrastructure and a set of complementary cloud services that enable customers to build and run a wide range of applications and services within a highly available hosted environment.

[0074] In the example embodiment shown in FIG. 2, the physical components of CSPI 200 include one or more physical host machines or servers (e.g., 202, 206, 208), network virtualization devices (NVDs) (e.g., 210, 212), top-of-rack (TOR) switches (e.g., 214, 216), and physical networks (e.g., 218), and switches within physical network 218. The physical host machines or servers may host and execute various compute instances that participate in one or more subnets of the VCN. The compute instances may include virtual machine instances and bare metal instances. For example, the various compute instances shown in FIG. 1 may be hosted by the physical host machines shown in FIG. 2. The virtual machine compute instances in the VCN may be executed by one host machine or by multiple different host machines. The physical host machines may host virtual host machines, container-based hosts or functions, etc. The VNICs and VCN VRs shown in FIG. 1 may be executed by the NVDs shown in FIG. 2. The gateway shown in FIG. 1 may be executed by a host machine and / or by the NVD shown in FIG.

[0075] A host machine or server may run a hypervisor (also called a virtual machine monitor or VMM) that creates and enables a virtual environment on the host machine. The virtualized environment or virtual environment facilitates cloud-based computing. On a host machine, one or more computing instances may be created, executed, and managed by the hypervisor on the host machine. The hypervisor on the host machine enables the physical computing resources of the host machine (e.g., computing resources, memory resources, and network resources) to be shared among the various computing instances executed by the host machine.

[0076] For example, as shown in FIG. 2, host machines 202 and 208 run hypervisors 260 and 266, respectively. These hypervisors may be implemented using software, firmware, or hardware, or a combination thereof. Typically, a hypervisor is a process or software layer that resides on top of a host machine's operating system (OS), which runs on the host machine's hardware processor. A hypervisor provides a virtual environment by allowing the host machine's physical computing resources (e.g., processing resources such as processors / cores, memory resources, network resources) to be shared among various virtual machine computing instances executed by the host machine. For example, in FIG. 2, hypervisor 260 may reside on top of the host machine's OS and allows the host machine's 202 computing resources (e.g., processing resources, memory resources, and network resources) to be shared among computing instances (e.g., virtual machines) executed by the host machine 202. A virtual machine can have its own operating system (called a guest operating system), which may be the same as or different from the host machine's OS. The operating system of a virtual machine executed by a host machine may be the same or different from the operating system of another virtual machine executed by the same host machine. Thus, the hypervisor allows multiple operating systems to run in parallel with each other while sharing the same computing resources of the host machine. The host machines shown in FIG. 2 may have the same or different types of hypervisors.

[0077] A compute instance can be a virtual machine instance or a bare metal instance. In Figure 2, compute instance 268 on host machine 202 and compute instance 274 on host machine 208 are examples of virtual machine instances. Host machine 206 is an example of a bare metal instance that is provided to a customer.

[0078] In one example, an entire host machine may be provisioned to a single customer, and all of the one or more compute instances (either virtual machines or bare metal instances) hosted by that host machine belong to the same customer. In other examples, a host machine may be shared among multiple customers (i.e., multiple tenants). In such a multi-tenancy situation, a host machine may host virtual machine compute instances that belong to different customers. These compute instances may be members of different VCNs for different customers. In one embodiment, bare metal compute instances are hosted by bare metal servers that do not have a hypervisor. When bare metal compute instances are provisioned, a single customer or tenant maintains control of the physical CPU, memory, and network interfaces of the host machine hosting the bare metal instance, and the host machine is not shared with other customers or tenants.

[0079] As previously mentioned, each compute instance that is part of a VCN is associated with a VNIC that enables the compute instance to be a member of a subnet of the VCN. The VNIC associated with a compute instance facilitates communication of packets or frames to and from the compute instance. The VNIC is associated with the compute instance when the compute instance is created. In an embodiment, for a compute instance executed by a host machine, the VNIC associated with the compute instance is executed by the NVD connected to the host machine. For example, in FIG. 2, host machine 202 executes virtual machine compute instance 268 that is associated with VNIC 276, which is executed by NVD 210 connected to host machine 202. As another example, bare metal instance 272 hosted by host machine 206 is associated with VNIC 280 that is executed by NVD 212 connected to host machine 206. As yet another example, VNIC 284 is associated with compute instance 274 executed by host machine 208, which is executed by NVD 212 connected to host machine 208.

[0080] For compute instances hosted by a host machine, the NVD connected to that host machine also runs VCN VRs corresponding to the VCNs of which those compute instances are members. For example, in the embodiment shown in Figure 2, NVD 210 runs VCN VR 277 corresponding to the VCN of which compute instance 268 is a member. NVD 212 may run one or more VCN VRs 283 corresponding to the VCNs corresponding to the compute instances hosted by host machines 206 and 208.

[0081] A host machine may include one or more network interface cards (NICs) that allow the host machine to be connected to other devices. The NICs on a host machine may provide one or more ports (or interfaces) that allow the host machine to be communicatively connected to another device. For example, a host machine may be connected to an NVD using one or more ports (or interfaces) provided on the host machine and the NVD. A host machine may be connected to other devices, such as another host machine.

[0082] 2, host machine 202 is connected to NVD 210 using link 220 extending between port 234 provided by NIC 232 of host machine 202 and port 236 of NVD 210. Host machine 206 is connected to NVD 212 using link 224 extending between port 246 provided by NIC 244 of host machine 206 and port 248 of NVD 212. Host machine 208 is connected to NVD 212 using link 226 extending between port 252 provided by NIC 250 of host machine 208 and port 254 of NVD 212.

[0083] The NVDs are then connected via communication links to top-of-rack (TOR) switches (also called switch fabrics) that are connected to a physical network 218. In one embodiment, the links between the host machines and the NVDs and between the NVDs and the TOR switches are Ethernet links. For example, in FIG. 2, links 228 and 230 are used to connect NVDs 210 and 212 to TOR switches 214 and 216, respectively. In one embodiment, links 220, 224, 226, 228, and 230 are Ethernet links. The collection of host machines and NVDs connected to a TOR may be referred to as a rack.

[0084] The physical network 218 provides a communications fabric that allows the TOR switches to communicate with each other. The physical network 218 can be a multi-tier network. In one implementation, the physical network 218 is a multi-tier Clos network of switches, with the TOR switches 214 and 216 representing leaf-level nodes of the multi-tier, multi-node physical switching network 218. A variety of Clos network configurations are possible, including, but not limited to, two-tier networks, three-tier networks, four-tier networks, five-tier networks, and generally, "n"-tier networks. An example Clos network is shown in FIG. 5 and described below.

[0085] Various connection configurations are possible between host machines and NVDs, such as one-to-one, many-to-one, and one-to-many configurations. In a one-to-one implementation, each host machine is connected to its own separate NVD. For example, in FIG. 2, host machine 202 is connected to NVD 210 via NIC 232 of host machine 202. In a many-to-one configuration, multiple host machines are connected to one NVD. For example, in FIG. 2, host machines 206 and 208 are connected to the same NVD 212 via NICs 244 and 250, respectively.

[0086] In a one-to-many configuration, one host machine is connected to multiple NVDs. Figure 3 shows an example in CSPI 300 where a host machine is connected to multiple NVDs. As shown in Figure 3, a host machine 302 includes a network interface card (NIC) 304 that includes multiple ports 306 and 308. The host machine 300 is connected to a first NVD 310 via port 306 and link 320, and to a second NVD 312 via port 308 and link 322. The ports 306 and 308 may be Ethernet ports, and the links 320 and 322 between the host machine 302 and the NVDs 310 and 312 may be Ethernet links. The NVD 310 is then connected to a first TOR switch 314, and the NVD 312 is connected to a second TOR switch 316. The links between the NVDs 310 and 312 and the TOR switches 314 and 316 may be Ethernet links. TOR switches 314 and 316 represent layer 0 switching devices in a multi-tier physical network 318 .

[0087] 3 provides two separate physical network paths between the physical switch network 318 and the host machine 302: a first path traversing the TOR switch 314 through the NVD 310 to the host machine 302, and a second path traversing the TOR switch 316 through the NVD 312 to the host machine 302. The separate paths result in improved availability (called high availability) of the host machine 302. If there is a problem with one of the paths (e.g., a link in one of the paths fails) or devices (e.g., a particular NVD is not functioning), the other path may be used for communication to and from the host machine 302.

[0088] In the configuration shown in Figure 3, the host machine is connected to two different NVDs using two different ports provided by the host machine's NIC. In other embodiments, the host machine may include multiple NICs allowing the host machine to be connected to multiple NVDs.

[0089] Referring again to Figure 2, an NVD is a physical device or component that performs one or more network and / or storage virtualization functions. An NVD may be any device that has one or more processing units (e.g., CPUs, Network Processing Units (NPUs), FPGAs, packet processing pipelines, etc.), memory including caches, and ports. Various virtualization functions may be performed by software / firmware executed by the one or more processing units of the NVD.

[0090] The NVD may be implemented in various forms. For example, in one embodiment, the NVD is implemented as an interface card called a smart NIC or intelligent NIC that contains an embedded processor. A smart NIC is a separate device from the NIC on the host machine. In FIG. 2, the NVDs 210 and 212 may be implemented as smart NICs connected to the host machine 202 and the host machines 206 and 208, respectively.

[0091] However, smart NICs are just one example of an implementation of the NVD. Various other implementations are possible. For example, in some other implementations, the NVD or one or more functions performed by the NVD may be incorporated in or performed by one or more host machines, one or more TOR switches, and other components of CSPI200. For example, the NVD may be embodied in a host machine, and the functions performed by the NVD are performed by the host machine. As another example, the NVD may be part of a TOR switch, or the TOR switch may be configured to perform the functions performed by the NVD, which allows the TOR switch to perform various complex packet transformations used in public clouds. A TOR that performs the functions of the NVD may be referred to as a smart TOR. In still other implementations where customers are provided with virtual machine (VM) instances rather than bare metal (BM) instances, the functions performed by the NVD may be implemented inside the hypervisor of the host machine. In some other implementations, some of the functions of the NVD may be offloaded to a centralized service running on a set of host machines.

[0092] In one embodiment, such as when implemented as a smart NIC as shown in FIG. 2, the NVD may comprise multiple physical ports that allow the NVD to be connected to one or more host machines and one or more TOR switches. Ports on the NVD may be classified as host-facing ports (also referred to as "south ports") or network-facing or TOR-facing ports (also referred to as "north ports"). The host-facing ports of the NVD are the ports used to connect the NVD to the host machines. Examples of host-facing ports in FIG. 2 include port 236 on the NVD 210, and ports 248 and 254 on the NVD 212. The network-facing ports of the NVD are the ports used to connect the NVD to the TOR switches. Examples of network-facing ports in FIG. 2 include port 256 on the NVD 210 and port 258 on the NVD 212. As shown in FIG. 2, the NVD 210 is connected to the TOR switch 214 using a link 228 that extends from port 256 of the NVD 210 to the TOR switch 214. Similarly, the NVD 212 is connected to the TOR switch 216 using a link 230 that extends from a port 258 of the NVD 212 to the TOR switch 216 .

[0093] The NVD may receive packets and frames (e.g., packets and frames generated by compute instances hosted by the host machine) from the host machine via a host-facing port, and after performing any necessary packet processing, may forward those packets and frames to the TOR switch via the NVD's network-facing port. The NVD may receive packets and frames from the TOR switch via the NVD's network-facing port, and after performing any necessary packet processing, may forward those packets and frames to the host machine via the NVD's host-facing port.

[0094] In an embodiment, there may be multiple ports and associated links between the NVD and the TOR switch. These ports and links may be aggregated to form a link aggregator group (called a link aggregator group (LAG)) of multiple ports or links. Link aggregation allows multiple physical links between two endpoints (e.g., between the NVD and the TOR switch) to be treated as a single logical link. All physical links within a particular LAG may operate in full-duplex mode at the same speed. LAGs help increase bandwidth and improve the reliability of the connection between two endpoints. If one of the physical links in the LAG fails, traffic is dynamically and transparently reassigned to one of the other physical links in the LAG. The aggregated physical link provides higher bandwidth than an individual link. Multiple ports associated with a LAG are treated as a single logical port. Traffic may be load-balanced across the multiple physical links of the LAG. One or more LAGs may be configured between two endpoints. Two endpoints may exist between the NVD and the TOR switch, between a host machine and the NVD, etc.

[0095] The NVD implements or performs network virtualization functions. These functions are performed by software / firmware executed by the NVD. Examples of network virtualization functions include, but are not limited to, packet encapsulation and decapsulation functions, functions for creating VCN networks, functions for enforcing network policies such as VCN security list (firewall) functions, functions for facilitating routing and forwarding of packets to and from compute instances in the VCN, etc. In an embodiment, upon receipt of a packet, the NVD is configured to execute a packet processing pipeline to process the packet and determine how the packet is to be forwarded or routed. As part of this packet processing pipeline, the NVD may perform one or more virtual functions associated with the overlay network, such as running a VNIC associated with a cis in the VCN, running a virtual router (VR) associated with the VCN, encapsulating and decapsulating packets to facilitate forwarding or routing within the virtual network, running certain gateways (e.g., local peering gateways), enforcing security lists, network security groups, network address translation (NAT) functions (e.g., per-host public IP to private IP translation), bandwidth throttling functions, and other functions.

[0096] In one embodiment, the packet processing data path within the NVD may comprise multiple packet pipelines, each consisting of a series of packet transformation stages. In one implementation, upon receipt of a packet, the packet is parsed and sorted into a single pipeline. The packet is then processed in a linear fashion, one stage at a time, until the packet is either dropped or sent out via an interface of the NVD. These stages provide the basic functional packet processing building blocks (e.g., authenticate headers, perform bandwidth throttling, insert new layer 2 headers, perform L4 firewalling, VCN encapsulation / decapsulation, etc.), such that new pipelines can be constructed by assembling existing stages, and new functionality can be added by creating and inserting new stages into existing pipelines.

[0097] The NVD may perform both control plane and data plane functions corresponding to the control and data planes of the VCN. Examples of the VCN control plane are also shown in Figures 12, 13, 14, and 15 (see reference numbers 1216, 1316, 1416, and 1516) and described below. Examples of the VCN data plane are shown in Figures 12, 13, 14, and 15 (see reference numbers 1218, 1318, 1418, and 1518) and described below. The control plane functions include functions used to configure the network (e.g., set routes and route tables, configure VNICs, etc.) that control how data is forwarded. In one embodiment, a VCN control plane is provided that centrally computes mappings between all overlays and infrastructure and publishes those mappings to the NVD and to virtual network edge devices such as various gateways such as DRGs, SGWs, IGWs, etc. The same mechanism may be used to publish firewall rules. In one embodiment, the NVD retrieves only mappings that are relevant to the NVD. The data plane functions include functionality for the actual routing / forwarding of packets based on configuration settings using the control plane. The VCN data plane is implemented by encapsulating customer network packets before they traverse the underlying network. The encapsulation / decapsulation functions are implemented in the NVD. In one embodiment, the NVD is configured to intercept all network packets entering and leaving the host machine and perform network virtualization functions.

[0098] As indicated above, the NVD performs various virtualization functions including VNICs and VCN VRs. The NVD may execute VNICs associated with compute instances hosted by one or more host machines connected to the VNICs. For example, as shown in FIG. 2, the NVD 210 executes functions of the VNIC 276 associated with the compute instance 268 hosted by the host machine 202 connected to the NVD 210. As another example, the NVD 212 executes VNIC 280 associated with the bare metal compute instance 272 hosted by the host machine 206 and executes VNIC 284 associated with the compute instance 274 hosted by the host machine 208. The host machines may host compute instances belonging to different VCNs belonging to different customers, and the NVDs connected to the host machines may execute VNICs (i.e., execute functions related to the VNICs) corresponding to the compute instances.

[0099] NVDs also run VCN virtual routers corresponding to the VCNs of compute instances. For example, in the embodiment shown in FIG. 2, NVD 210 runs VCN VR 277 corresponding to the VCN to which compute instance 268 belongs. NVD 212 runs one or more VCN VRs 283 corresponding to one or more VCNs to which compute instances hosted by host machines 206 and 208 belong. In an embodiment, a VCN VR corresponding to that VCN is run by all NVDs connected to a host machine that hosts at least one compute instance that belongs to that VCN. If a host machine hosts compute instances that belong to different VCNs, the NVDs connected to that host machine may run VCN VRs corresponding to those different VCNs.

[0100] In addition to the VNICs and VCN VRs, the NVD may run various software (e.g., daemons) and may include one or more hardware components that facilitate various network virtualization functions performed by the NVD. For simplicity, these various components are grouped together as a "packet processing component" shown in FIG. 2. For example, the NVD 210 includes a packet processing component 286, and the NVD 212 includes a packet processing component 288. For example, the packet processing component of the NVD may include a packet processor configured to interact with the ports and hardware interfaces of the NVD to monitor all packets received by and communicated using the NVD and to store network information. The network information may include, for example, network flow information and per-flow information (e.g., per-flow statistics) that identify various network flows processed by the NVD. In an embodiment, the network flow information may be stored per VNIC. In addition to performing per-packet operations, the packet processor may implement a stateful NAT and an L4 firewall (FW). As another example, the packet processing component may include a replication agent configured to replicate information stored by the NVD to one or more distinct replication target stores. As yet another example, the packet processing component may include a logging agent configured to perform logging functions for the NVD. The packet processing component may also include software for monitoring the performance and health of the NVD, and possibly software for monitoring the status and health of other components connected to the NVD.

[0101] FIG. 1 illustrates components of an exemplary virtual or overlay network, including a VCN, a subnet in the VCN, compute instances deployed in the subnet, VNICs associated with the compute instances, VRs of the VCN, and a set of gateways configured for the VCN. The overlay components illustrated in FIG. 1 may be executed or hosted by one or more of the physical components illustrated in FIG. 2. For example, the compute instances in the VCN may be executed or hosted by one or more host machines illustrated in FIG. 2. For a compute instance hosted by a host machine, the VNICs associated with the compute instance are typically executed by the NVD connected to the host machine (i.e., the VNIC functionality is provided by the NVD connected to the host machine). The VCN VR functionality of the VCN is executed by all NVDs connected to the host machines that host or are running compute instances that are part of the VCN. The gateways associated with the VCN may be executed by one or more different types of NVDs. For example, some gateways may be executed by smart NICs, while other gateways may be executed by one or more host machines or other implementations of NVDs.

[0102] As previously mentioned, compute instances in a customer's VCN may communicate with various endpoints, which may be in the same subnet as the source compute instance, or in a different subnet within the same VCN as the source compute instance, or the endpoints may be outside the VCN of the source compute instance. These communications are facilitated using VNICs associated with the compute instances, VCN VRs, and gateways associated with the VCN.

[0103] For communication between two compute instances on the same subnet within a VCN, the communication is facilitated using a VNIC associated with the source compute instance and the destination compute instance. The source compute instance and the destination compute instance may be hosted by the same host machine or by different host machines. A packet originating from the source compute instance may be forwarded from the host machine hosting the source compute instance to an NVD connected to that host machine. In the NVD, the packet is processed using a packet processing pipeline, which may include execution of the VNIC associated with the source compute instance. Because the destination endpoint of the packet is in the same subnet, execution of the VNIC associated with the source compute instance causes the packet to be forwarded to an NVD running the VNIC associated with the destination compute instance, which then processes and forwards the packet to the destination compute instance. The VNICs associated with the source and destination compute instances may run on the same NVD (e.g., when the source and destination compute instances are both hosted by the same host machine) or on different NVDs (e.g., when the source and destination compute instances are hosted by different host machines connected to different NVDs). The VNICs may use routing / forwarding tables stored by the NVD to determine the next hop of a packet.

[0104] For packets traveling from a compute instance in a subnet to an endpoint in a different subnet in the same VCN, the packet originating from the source compute instance is traveled from the host machine hosting the source compute instance to the NVD connected to that host machine. In the NVD, the packet is processed using a packet processing pipeline, which may include the execution of one or more VNICs and VRs associated with the VCN. For example, as part of the packet processing pipeline, the NVD executes or invokes a function corresponding to the VNIC associated with the source compute instance (also referred to as executing the VNIC). The function executed by the VNIC may include examining the VLAN tag on the packet. Because the destination of the packet is outside the subnet, a VCN VR function is then invoked and executed by the NVD. The VCN VR then routes the packet to the NVD that is executing the VNIC associated with the destination compute instance. The VNIC associated with the destination compute instance then processes the packet and forwards the packet to the destination compute instance. The VNICs associated with the source compute instance and the destination compute instance may run on the same NVD (e.g., when the source compute instance and the destination compute instance are both hosted by the same host machine) or on different NVDs (e.g., when the source compute instance and the destination compute instance are hosted by different host machines connected to different NVDs).

[0105] If the packet's destination is outside the VCN of the source compute instance, the packet originating from the source compute instance is conveyed from the host machine hosting the source compute instance to the NVD connected to that host machine. The NVD runs the VNIC associated with the source compute instance. Because the packet's destination endpoint is outside the VCN, the packet is then processed by the VCN VR for that VCN. The NVD may invoke a VCN VR function to cause the packet to be forwarded to an NVD running an appropriate gateway associated with the VCN. For example, if the destination is an endpoint in the customer's on-premises network, the packet may be forwarded by the VCN VR to an NVD running a DRG gateway configured for the VCN. The VCN VR may be executed on the same NVD as the NVD running the VNIC associated with the source compute instance or by a different NVD. The gateway may be executed by the NVD, which can be a smart NIC, a host machine, or another NVD implementation. The packet is then processed by the gateway and forwarded to a next hop that facilitates the packet's conveyance to the intended destination endpoint. 2, a packet originating from compute instance 268 may be communicated from host machine 202 (using NIC 232) to NVD 210 via link 220. At NVD 210, VNIC 276 is invoked because it is the VNIC associated with source compute instance 268. VNIC 276 is configured to examine information encapsulated within the packet, determine a next hop for forwarding the packet in order to facilitate communication of the packet to an intended destination endpoint, and then forward the packet to the determined next hop.

[0106] Compute instances deployed in a VCN may communicate with various endpoints. These endpoints may include endpoints hosted by CSPI200 and endpoints outside of CSPI200. Endpoints hosted by CSPI200 may include instances in the same VCN or other VCNs, which may be the customer's VCN or VCNs not belonging to the customer. Communications between endpoints hosted by CSPI200 may be performed over physical network 218. Compute instances may communicate with endpoints not hosted by CSPI200 or outside of CSPI200. Examples of these endpoints include endpoints in a customer's on-premise network or data center, or public endpoints accessible over a public network such as the Internet. Communications with endpoints outside of CSPI200 may be performed over a public network (e.g., the Internet) (not shown in FIG. 2) or a private network (not shown in FIG. 2) using various communication protocols.

[0107] The architecture of CSPI 200 shown in FIG. 2 is merely an example and is not intended to be limiting. In alternative embodiments, variations, alternatives, and modifications are possible. For example, in some implementations, CSPI 200 may include more or fewer systems or components than those shown in FIG. 2, may combine two or more systems, or may include a different configuration or arrangement of systems. The systems, subsystems, and other components shown in FIG. 2 may be implemented in software (e.g., code, instructions, programs) executed by one or more processing units (e.g., processors, cores) of the respective systems, using hardware, or a combination thereof. The software may be stored in a non-transitory storage medium (e.g., in a memory device).

[0108] FIG. 4 illustrates a connection between a host machine and an NVD to provide I / O virtualization to support multitenancy functionality, according to an embodiment. As illustrated in FIG. 4, a host machine 402 runs a hypervisor 404 that provides a virtual environment. The host machine 402 runs two virtual machine instances, VM1 406 belonging to customer / tenant #1 and VM2 408 belonging to customer / tenant #2. The host machine 402 includes a physical NIC 410 that is connected to an NVD 412 via link 414. Each of the compute instances is connected to a VNIC that is executed by the NVD 412. In the embodiment of FIG. 4, VM1 406 is connected to VNIC-VM1 420, and VM2 408 is connected to VNIC-VM2 422.

[0109] 4, NIC 410 includes two logical NICs, logical NIC A 416 and logical NIC B 418. Each virtual machine is connected to and configured to function with its own logical NIC. For example, VM1 406 is connected to logical NIC A 416, and VM2 408 is connected to logical NIC B 418. Because of the logical NICs, each tenant's virtual machine has the assurance that it has its own host machine and NIC, even though host machine 402 includes only one physical NIC 410 that is shared by multiple tenants.

[0110] In one embodiment, each logical NIC is assigned its own VLAN ID. Thus, a particular VLAN ID is assigned to logical NIC A 416 for tenant #1, and another VLAN ID is assigned to logical NIC B 418 for tenant #2. When a packet is communicated from VM1 406, a tag assigned to tenant #1 is attached to the packet by the hypervisor, and the packet is then communicated from host machine 402 to NVD 412 via link 414. In a similar manner, when a packet is communicated from VM2 408, a tag assigned to tenant #2 is attached to the packet by the hypervisor, and the packet is then communicated from host machine 402 to NVD 412 via link 414. Thus, a packet 424 communicated from host machine 402 to NVD 412 has an associated tag 426 that identifies the particular tenant and associated VM. At the NVD, for a packet 424 received from a host machine 402, a tag 426 associated with the packet is used to determine whether the packet should be processed by VNIC-VM1 420 or VNIC-VM2 422. The packet is then processed by the corresponding VNIC. The configuration shown in Figure 4 allows each tenant's compute instance to be confident that it owns its own host machine and NIC. The setup shown in Figure 4 enables I / O virtualization to support multi-tenancy capabilities.

[0111] FIG. 5 illustrates a simplified block diagram of a physical network 500, according to an embodiment. The embodiment illustrated in FIG. 5 is structured as a Clos network. A Clos network is a particular type of network topology designed to provide connection redundancy while maintaining high bisection bandwidth and maximum resource utilization. A Clos network is a type of non-blocking multi-stage or multi-layer switching network, the number of stages or layers of which can be two, three, four, five, etc. The embodiment illustrated in FIG. 5 is a three-layer network, including layers 1, 2, and 3. A TOR switch 504 represents a layer 0 switch in a Clos network. One or more NVDs are connected to a TOR switch. A layer 0 switch is also referred to as an edge device of the physical network. A layer 0 switch is connected to a layer 1 switch, also referred to as a leaf switch. In the embodiment illustrated in FIG. 5, a set of "n" layer 0 TOR switches are connected to a set of "n" layer 1 switches, together forming a pod. Each layer 0 switch in a pod is interconnected to all layer 1 switches within the pod, but there are no switch connections between pods. In one implementation, the two pods are referred to as blocks. Each block is served by or connected to a set of "n" layer 2 switches (sometimes referred to as spine switches). There can be multiple blocks in a physical network topology. The layer 2 switches are then connected to "n" layer 3 switches (sometimes referred to as super spine switches). Communication of packets through the physical network 500 is typically performed using one or more layer 3 communication protocols. Typically, all layers of the physical network except the TOR layer have n-way redundancy, thus enabling high availability. Policies may be specified for pods and blocks to control the visibility of switches to each other within the physical network to enable scaling of the physical network.

[0112] A feature of Clos networks is that the maximum number of hops to reach from one tier 0 switch to another tier 0 switch (or from an NVD connected to a tier 0 switch to another NVD connected to a tier 0 switch) is fixed. For example, in a three-tier Clos network, a maximum of seven hops are required for a packet to reach from one NVD to another, with the source NVD and the target NVD connected to the leaf layer of the Clos network. Similarly, in a four-tier Clos network, a maximum of nine hops are required for a packet to reach from one NVD to another, with the source NVD and the target NVD connected to the leaf layer of the Clos network. Thus, the Clos network architecture maintains consistent latency throughout the network, which is important for intra- and inter-datacenter communications. Clos topologies scale horizontally and are cost-effective. The bandwidth / throughput capacity of the network can be easily increased by adding more switches (e.g., more leaf switches and spine switches) to various tiers and by increasing the number of links between switches at adjacent tiers.

[0113] In one embodiment, each resource in the CSPI is assigned a unique identifier called a Cloud Identifier (CID). This identifier is included as part of the resource's information and can be used to manage the resource, for example, via a console or via an API. An exemplary syntax for a CID is as follows: ocid1.<RESOURCE TYPE> . <realm>.[REGION][.FUTURE USE].<UNIQUE ID> Where: ocid1: A literal column that indicates the version of the CID. RESOURCE TYPE: The type of resource (for example, instance, volume, VCN, subnet, user, group, etc.). REALM: The realm in which the resource resides. Example values ​​are "c1" for a commercial realm, "c2" for a government cloud realm, or "c3" for a federal cloud realm, etc. Each realm may have its own domain name. REGION: The region the resource is in. This part may be blank if a region is not applicable to the resource. FUTURE USE: Reserved for future use. UNIQUE ID: The unique part of the ID. This format may vary depending on the type of resource or service.

[0114] Remote Direct Memory Access (RDMA) provides the high throughput and ultra-low latency required for modern data center applications with low CPU overhead. RDMA is deployed over Ethernet using the RDMA over converged Ethernet (RoCE) protocol, which relies on Priority-Based Flow Control (PFC) to enable a lossless (i.e., no packet drops) network. Data Center Quantized Congestion Notification (DC-QCN) is an end-to-end congestion control scheme for RoCE. DC-QCN is supported by combining Explicit Congestion Notification (ECN) and PFC to overcome the limitations of PFC and support an end-to-end lossless network.

[0115] Priority-Based Flow Control (PFC) is a lossless transport and congestion mitigation feature that works by providing fine-grained link-level flow control for each traffic flow (with priority) on a full-duplex Ethernet link. When a receive buffer on a switch interface fills up and reaches a threshold, the switch sends a pause frame to the sender (connected peer) to temporarily stop the sender from sending any more frames. Note that the buffer threshold must get low enough before the buffer overflows to allow the sender time to stop sending frames and for the receiver to receive frames already on the wire. The switch automatically sets the queue buffer threshold to prevent frame loss.

[0116] According to some embodiments, if congestion forces a flow of one priority on a link to be paused, all other priority flows on the link continue to transmit frames; only frames of the paused priority are not transmitted. When the receive buffer empties below another threshold, the switch sends a message to resume the flow. However, depending on the amount of traffic on the link or the assigned priorities, pausing traffic may cause congestion at the ingress port and thus eventually spread congestion throughout the network.

[0117] Explicit Congestion Notification (ECN) allows end-to-end congestion notification between two endpoints. ECN is an IP-level flag used by higher layer protocols such as UDP and TCP. The two endpoints are an ECN-enabled sender and an ECN-enabled receiver. In a preferred embodiment, ECN is enabled at both endpoints and at all of the intermediate devices between the endpoints. In some embodiments, for intermediate devices that do not support ECN (i.e., non-ECN devices), end-to-end ECN functionality may be degraded. Note that for non-ECN devices, congestion is detected simply based on packets dropped by the non-ECN device. ECN notifies the network of congestion without dropping packets, with the goal of reducing packet loss and delay by reducing the sending rate of the sending device until the congestion is cleared.

[0118] Data Center Quantized Congestion Notification (DC-QCN) is a combination of ECN and PFC to support end-to-end lossless Ethernet. ECN helps overcome the limitations of PFC to achieve lossless Ethernet. The idea behind DC-QCN is to allow ECN to perform flow control by slowing down the sending rate when congestion begins, thereby minimizing the time when PFC is triggered to completely stop the flow. The correct operation of DC-QCN requires balancing two conflicting requirements: (1) PFC should not be triggered too early, i.e., before ECN has a chance to send congestion feedback to slow down the flow, and (2) PFC should not be triggered too late, thereby causing packet loss due to buffer overflow. It is noted that to meet the above key requirements, key parameters need to be properly calculated and configured. Typically, workloads such as general purpose processing unit (GPU) workloads cannot get the desired level of throughput while running on a cluster network. One of the causes of this problem is that the RoCE congestion management performed on RDMA network interface cards (NICs) is not optimized, i.e., the parameters of various network level devices and NICs on the host machine are not optimized to improve network throughput. In the following, a framework and mechanism are described that classifies the types of traffic classes of data packets (e.g., RDMA traffic classes) and provisions users to handle various traffic classes in a specific way.

[0119] 6, an exemplary tree diagram illustrating various parameter settings, according to an embodiment, is shown. According to some embodiments, the parameter settings may be categorized into two types or levels: the network device level, i.e., parameter settings performed on network devices in the communication path between the source host machine and the destination host machine, and the network interface card (NIC) level, e.g., parameter settings performed on a NIC associated with the source host machine.

[0120] The parameters associated with the network device level may include parameters corresponding to ECN markings of various classes of RDMA traffic and queue (i.e., buffer) depths utilized in the network device. In some embodiments, RDMA traffic may be classified as high performance database RDMA traffic (e.g., Oracle Exadata traffic), high performance computing RDMA traffic (i.e., latency sensitive type of RDMA traffic), and graphical processing unit (GPU) workload traffic (i.e., bandwidth intensive type of RDMA traffic). As described below with reference to FIG. 8, various parameters may be set to specific values ​​to handle each of the aforementioned types of RDMA traffic in a unique manner. With respect to queue depths, it is understood that bandwidth intensive RDMA traffic, e.g., GPU workload traffic, may utilize more buffers, i.e., a larger queue depth, compared to the case involving latency sensitive RDMA traffic, where a smaller queue depth is utilized.

[0121] With regard to parameter settings performed at the network interface card (NIC) level, i.e., the NIC on the source host machine, the parameters that are set may include an adaptive retransmission parameter, a multiple queue pairs parameter, a slow restart parameter, and a packet sequence number parameter. According to some embodiments, the adaptive retransmission parameter is a binary parameter (i.e., an on / off parameter) that corresponds to the time it takes for the sending host machine (or the receiving host machine) to recover when there is an interruption at the other party, i.e., the receiving host machine (or the sending host machine). In some implementations, the adaptive retransmission parameter is set to on. The multiple queue pairs parameter corresponds to the number of queues utilized by the NIC in handling different classes of traffic. For example, according to some embodiments, for latency-sensitive RDMA traffic, the number of queue pairs is set to 1, while for bandwidth-sensitive RDMA traffic, the number of queue pairs is set to 4.

[0122] The slow restart parameter controls the rate at which the queue grows. In particular, in some implementations, the slow restart parameter is a binary parameter (i.e., an on / off parameter) that is set on to prevent bursty traffic. The packet sequence number (PSN) parameter corresponds to the number of packets that can be on the wire (i.e., in transit) at any particular time. In some embodiments, the PSN parameter is typically set to 2 7 In some implementations, the PSN parameter has a default value of 2 9 The PSN parameter is set to a larger value (e.g., 2 9 It is understood that setting the PSN parameter to a larger value will cause a larger number of packet retransmissions to handle packet losses. Furthermore, in some implementations, the PSN parameter is made programmable, i.e., the parameter is configurable such that it can be set to any desired value.

[0123] Referring now to FIG. 7, an exemplary tree diagram illustrating various configuration options for Differentiated Services Code Point (DSCP) configuration, according to an embodiment, is shown. In some implementations, a user is provided with the flexibility to tag (i.e., set) a portion of a data packet's header to indicate a desired traffic type or traffic class to which the packet belongs. For example, in some implementations, a source (e.g., an application running on a source host machine) may be configured to set a portion of a packet's header to indicate a type of traffic class associated with the packet. In so doing, the data packet is treated (i.e., processed) in a manner specific to the traffic type. For example, parameters at the network device level and parameters at the NIC level may be set in a certain manner to process the data packet (belonging to the traffic class) in an optimal manner.

[0124] In some embodiments, a header of a data packet (e.g., an IP header) may include a type of service (TOS) field that is one byte long (i.e., 8 bits). Two bits of the TOS field may be reserved for Explicit Congestion Notification (ECN) use, while the remaining 6 bits may be utilized for Differentiated Services Code Point (DSCP) use. Thus, the DSCP bits may be marked in a particular manner to indicate the desired traffic type of the data packet and the corresponding treatment, e.g., how an ECN packet of the traffic class is to be treated.

[0125] According to one embodiment, the DSCP bits may be marked to indicate that the data packet belongs to a type of RDMA traffic that may be latency sensitive or bandwidth intensive. Thus, the ECN may be set by one of a deterministic marking scheme, a probabilistic marking scheme, a relaxed marking scheme, an aggressive marking scheme, or a combination thereof, i.e., deterministic and aggressive or relaxed probabilistic. Such ECN marking schemes are described later with reference to FIG. 8. Furthermore, the DSCP bits may be utilized to indicate whether the data packet belongs to lossy TCP type traffic or whether the data packet belongs to DC-QCN managed type traffic.

[0126] As shown in FIG. 7, a first level of traffic classification may be obtained by marking the DSCP bits in a particular way, i.e., setting the DSCP bits to indicate the type of traffic, such as latency sensitive RDMA traffic, bandwidth intensive RDMA traffic, etc. At the second level, (Q 1 -Q K Multiple queue pairs (labeled as 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 110, 111, 120, 130, 140, 150, 160, 170, 180, 190, 191, 192, 193, 194, 195, 196, 197, 198, 199, 200, 210, 220, 230, In one implementation, for latency-sensitive traffic, the thresholds associated with the queues are kept low and a deterministic marking scheme is employed, while for bandwidth-intensive traffic, the thresholds associated with the queues are kept high and a probabilistic marking scheme is employed. Multiple queues may be utilized to increase application throughput through parallelism. Additionally, note that in some implementations, multiple latency-sensitive traffic classes may be used to prevent situations where different types of latency-sensitive traffic cause queuing (and thus jitter) with each other. In other words, multiple latency-sensitive queues may be utilized to prevent head-of-line (HOL) blocking situations.

[0127] FIG. 8 illustrates a schematic diagram illustrating a mechanism utilized to mark Explicit Congestion Notification (ECN) packets, according to an embodiment. In particular, FIG. 8 illustrates a schematic diagram illustrating how a switch marks ECN packets for different types of RDMA traffic. As shown in FIG. 8, the x-axis is labeled as the switch's egress queue size, and the y-axis is labeled as the marking probability, i.e., the probability that a particular packet will be marked as an ECN packet. According to some embodiments, a switch, e.g., a TOR switch, a spine switch, etc., may: (1) determine a minimum threshold parameter (K) defined in terms of a segment or packet; min ),(2) A maximum threshold parameter (K max ), and (3) a marking probability parameter. Note that in some embodiments, a segment may be 208 bytes long.

[0128] In one implementation, the switch monitors the buffer depth (i.e., the number of segments in the queue) for each traffic class. When the buffer reaches a “minimum” ECN threshold (i.e., K min ), the switch begins marking the ECN bits of the packet. Marking may be performed in one of two ways: (1) a random manner (i.e., a probabilistic manner), where the probability that a particular packet will be marked is defined by a configured marking probability, or (2) a deterministic manner, where the probability of marking a packet is 100% based on certain conditions being met. Details regarding how to mark packets are described in more detail below.

[0129] In the probabilistic method of marking packets, the switch monitors the buffer depth (i.e., the number of segments in the queue) for each traffic class. When the buffer reaches a “minimum” ECN threshold (i.e., K min ), the switch starts marking the ECN bits of the packet. The buffer is filled to the maximum ECN threshold (i.e., K max ), the switch will send the maximum P max % of ECN bits are marked. In addition, some implementations may require the buffer depth to be greater than the maximum ECN threshold (i.e., K max ), 100% of packets are marked. min and K. max Between 0% and P max %, the switch linearly increases the % of packets marked. In contrast, in a deterministic method of marking packets, the switch maintains only a single threshold, i.e., the switch min =K max =K. In deterministic marking, the switch monitors the buffer depth (i.e., the number of segments present in the queue) for each of the traffic classes and performs marking as follows: if the buffer depth is less than K, no packets are marked, whereas if the buffer depth is greater than K, all packets are marked with a 100% marking probability. As explained below with reference to FIG. 9, the switch parameters, e.g., P max , K min , and K max may be set to a particular value based on the type of traffic handled by the switch for optimal throughput performance.

[0130] FIG. 9 illustrates different parameter settings for different types of RDMA traffic (i.e., parameters P max , K min , and K max 9 shows a table showing the values ​​of K, ... min =2000,K max = 10,000, and probability P max =20%.

[0131] Furthermore, as shown in the table of FIG. 9, for latency-sensitive RDMA applications, the switch may implement a "deterministic and aggressive" mechanism for marking ECN packets. In particular, for such traffic types (e.g., high performance computing traffic), the parameters K min =50,K max = 50 (i.e., K min =K max =K), and the probability of marking P max = 100%. Thus, for such traffic types, the switch monitors the queue depth, and when it determines that the buffer exceeds K, the switch marks each subsequent packet with 100% probability. Furthermore, as previously described, multiple queue pairs may be utilized for optimal performance. For example, for bandwidth-intensive RDMA traffic, multiple queues (e.g., four queues) may be utilized, while for latency-sensitive RDMA applications, a single queue may be utilized.

[0132] Furthermore, when multiple queues exist for a type of traffic, priorities may be assigned to the different queues to provide preferential treatment for at least some of the queues. For example, considering high performance database traffic (i.e., Exadata), four deterministic queues may be utilized, with traffic in the first queue (of the four) being assigned a higher priority compared to the other queues. In some embodiments, the priorities may correspond to the bandwidth allocation of the queues, with the first queue being assigned 40% of the available bandwidth, while the remaining 60% of the bandwidth is distributed (e.g., equally) among the other three queues.

[0133] According to some embodiments, the specific parameter settings mentioned above based on the type of traffic being handled by the switch provide a 6x improvement in GPU workload performance, i.e., a 6x improvement over using the default settings for all types of RDMA traffic. The following table shows the performance enhancements obtained by increasing the number of nodes.

[0134] [Table 1]

[0135] FIG. 10 illustrates a schematic diagram 1000 identifying network locations in a cloud infrastructure where different parameter markings are applied, according to an embodiment. For convenience, a portion of a network cluster is illustrated in FIG. 10. As illustrated in FIG. 10, the network cluster may include one or more racks, e.g., rack 1 1010. Each rack may include one or more host machines, e.g., host 1-A 1012 and host 1-B 1014, contained in rack 1 1010. Each host machine may include one or more NIC ports, e.g., NIC port 1013 of host 1-A 1012 and NIC port 1015 of host 1-B 1014. Each of the host machine's NIC ports is connected to a host-facing port of a top-of-rack (TOR) switch, e.g., TOR1 1016. The TOR switch 1016 is in turn connected to a number of spine switches, e.g., spine 1, 1030 to spine P, 1040.

[0136] According to some embodiments, the TOR switch 1016 and the spine switches (e.g., spine 1, 1030 and spine P, 1040) enable ECN marking 1071 as described above. In particular, if there is any queuing on any port of these switches, the switches perform the ECN marking scheme (for different traffic classes) as described above with reference to FIG. 8. Furthermore, the TOR switch and the spine switches perform quality of service (QoS) marking. QoS marking enables the switch to decide which traffic class of data packets to place in which queue, i.e., QoS marking enables the switch to perform priority queuing of data packets, e.g., to decide which data packets to place in which queue. It is understood that such priority placement of data packets in the respective queues may be performed based on DSCP bits marked by the user at the end host. In some embodiments, the TOR switches and spine switches are also configured to assign highest priority to management queues, for example those carrying congestion notification packets (CNP), as such queues manage the end-to-end performance of the network cluster.

[0137] Additionally, priority flow control (PFC) settings 1072 are performed on the TOR ports facing the host machines in the rack, as shown in Figure 10. It is understood that the PFC settings operate on a per queue level and relate to the amount of buffer capacity borrowed by the host NIC from the TOR switch. Additionally, DSCP marking 1073 is performed by the host machine on data packets sent by the host machine to the TOR switch, as shown in Figure 10. Additionally, parameter settings related to adaptive retransmission, multiple queue pairs, slow restart, and packet sequence numbers are performed on the NIC ports of the host machines.

[0138] FIG. 11A illustrates an exemplary flowchart 1100 showing steps performed in processing a data packet based on a traffic class of the data packet, according to an embodiment. The process illustrated in FIG. 11A may be implemented in software (e.g., code, instructions, programs) executed by one or more processing units (e.g., processors, cores) of the respective system, hardware, or a combination thereof. The software may be stored in a non-transitory storage medium (e.g., in a memory device). The method presented in FIG. 11A and described below is intended to be exemplary and non-limiting. Although FIG. 11A illustrates various processing steps occurring in a particular sequence or order, this is not intended to be limiting. In an alternative embodiment, these steps may be performed in some different order, or some steps may be performed in parallel.

[0139] The process begins at step 1105, where a network device in a communication path between a source host machine and a destination host machine obtains a data packet sent by the source host machine. For example, with reference to Figure 10, the source host machine may correspond to Host 1-B 1014 (contained in Rack 1 1010), and the destination host machine may correspond to another host machine contained in another rack (not shown). Additionally, the network device may correspond to TOR1 switch 1016.

[0140] In step 1110, the network device processes the received data packet. For example, the network device extracts a tag included in a header portion of the data packet. The tag includes information indicating a traffic type of the data packet. It is understood that the tag may be set by an application running on a source host machine. For example, referring to FIG. 7, the DSCP bits included in the header portion of the data packet may be set in a specific manner to indicate a specific type of traffic to which the data packet belongs. According to some embodiments, the data packet may be one of a number of types of RDMA traffic, such as high performance database traffic (e.g., exadata traffic), high performance computing traffic (i.e., a latency-sensitive type of RDMA traffic), GPU workload traffic (i.e., a bandwidth-intensive type of RDMA traffic), RoCE v2 managed traffic, lossy TCP traffic, etc. The process then moves to step 1115, where the network device determines a traffic class (of the data packet) based on the information included in the tag.

[0141] In step 1120, the network device processes the data packet based on the traffic class determined in step 1115. For example, referring to Figure 6, network device level parameters and / or parameters associated with the NIC on the host machine may be set to particular values ​​as described above to process the data packet in a particular manner, i.e., based on the type of traffic class to which the data packet belongs.

[0142] FIG. 11B illustrates an exemplary flowchart 1130 showing steps performed in processing data packets belonging to a bandwidth-sensitive type of traffic class, according to an embodiment. The process illustrated in FIG. 11B may be implemented in software (e.g., code, instructions, programs) executed by one or more processing units (e.g., processors, cores) of the respective system, hardware, or a combination thereof. The software may be stored in a non-transitory storage medium (e.g., in a memory device). The method presented in FIG. 11B and described below is intended to be exemplary and non-limiting. Although FIG. 11B illustrates various processing steps occurring in a particular sequence or order, this is not intended to be limiting. In an alternative embodiment, these steps may be performed in some different order, or some steps may be performed in parallel.

[0143] The process begins at step 1135, where a network device in a communication path between a source host machine and a destination host machine obtains a data packet sent by the source host machine. For example, with reference to Figure 10, the source host machine may correspond to Host 1-B 1014 (contained in Rack 1 1010), and the destination host machine may correspond to another host machine contained in another rack (not shown). Additionally, the network device may correspond to TOR1 switch 1016.

[0144] In step 1140, the network device processes the received data packet. For example, the network device may extract a tag included in a header portion of the data packet. The tag includes information indicating a traffic type of the data packet. It is understood that the tag may be set by an application running on a source host machine. For example, referring to FIG. 7, a user may set a DSCP bit included in a header portion of the data packet in a specific manner to indicate a specific type of traffic to which the data packet belongs. According to some embodiments, the data packet may be one of a plurality of types of RDMA traffic, such as high performance database traffic, high performance computing (HPC) traffic (i.e., a latency-sensitive type of RDMA traffic), GPU workload traffic (i.e., a bandwidth-intensive type of RDMA traffic), RoCE v2 congestion control or congestion management type traffic, lossy TCP traffic, etc. The process then moves to step 1145, where the network device determines that the data packet belongs to a bandwidth-sensitive type of RDMA traffic based on the tag.

[0145] In step 1147, the network devices process the data packets in a manner corresponding to processing the bandwidth-sensitive type of RDMA traffic. For example, one or more settings associated with the bandwidth-sensitive type of RDMA traffic are applied to multiple network devices involved in communicating the data packets from a source host machine to a destination host machine. For example, the one or more settings associated with the bandwidth-sensitive type of RDMA traffic may be configured to have a probability of marking a packet set to 20% and a probability of marking a packet set to 20%. min = 2000 and K max It is understood that the method may include setting a value of .times. ...

[0146] FIG. 11C illustrates an exemplary flowchart 1150 showing steps performed in processing data packets belonging to a latency-sensitive type of traffic class, according to an embodiment. The process illustrated in FIG. 11C may be implemented in software (e.g., code, instructions, programs) executed by one or more processing units (e.g., processors, cores) of the respective system, hardware, or a combination thereof. The software may be stored in a non-transitory storage medium (e.g., in a memory device). The method presented in FIG. 11C and described below is intended to be exemplary and non-limiting. Although FIG. 11C illustrates various processing steps occurring in a particular sequence or order, this is not intended to be limiting. In an alternative embodiment, these steps may be performed in some different order, or some steps may be performed in parallel.

[0147] The process begins at step 1151, where a network device in a communication path between a source host machine and a destination host machine obtains a data packet sent by the source host machine. For example, with reference to Figure 10, the source host machine may correspond to Host 1-B 1014 (contained in Rack 1 1010), and the destination host machine may correspond to another host machine contained in another rack (not shown). Additionally, the network device may correspond to TOR1 switch 1016.

[0148] In step 1153, the network device processes the received data packet. For example, the network device may extract a tag included in the header portion of the data packet. The tag includes information indicating the type of traffic of the data packet. It is understood that the tag may be set by an application running on the source host machine. For example, referring to FIG. 7, a user may set the DSCP bit included in the header portion of the data packet in a specific manner to indicate the specific type of traffic to which the data packet belongs. According to some embodiments, the data packet may be one of a plurality of types of RDMA traffic, such as high performance database traffic, high performance computing traffic (i.e., a latency-sensitive type of RDMA traffic), GPU workload traffic (i.e., a bandwidth-intensive type of RDMA traffic), DC-QCN managed traffic, lossy TCP traffic, etc. The process then moves to step 1155, where the network device determines that the data packet belongs to the latency-sensitive type of RDMA traffic based on the tag.

[0149] In step 1157, the network devices process the data packets in a manner corresponding to processing the latency sensitive type of RDMA traffic. For example, one or more settings associated with the latency sensitive type of RDMA traffic are applied to multiple network devices involved in communicating the data packets from the source host machine to the destination host machine. The one or more settings associated with the latency sensitive type of RDMA traffic may, for example, be configured to have a probability of marking packets set to 100% and a probability of marking packets set to 100%. min =50 and K max It is understood that the method may include setting a value of .times. ...

[0150] FIG. 11D illustrates an exemplary flow chart 1170 showing steps performed in tagging a portion of a header of a data packet, according to an embodiment. The process illustrated in FIG. 11D may be implemented in software (e.g., code, instructions, programs) executed by one or more processing units (e.g., processors, cores) of the respective system, hardware, or a combination thereof. The software may be stored in a non-transitory storage medium (e.g., in a memory device). The method presented in FIG. 11D and described below is intended to be exemplary and non-limiting. Although FIG. 11D illustrates various processing steps occurring in a particular sequence or order, this is not intended to be limiting. In an alternative embodiment, these steps may be performed in some different order, or some steps may be performed in parallel.

[0151] The process begins at step 1171, where a source host machine prepares a data packet to be sent to a destination host machine. For example, referring to FIG. 10, a source host machine, e.g., Host 1-B 1014 (contained in Rack 1 1010), prepares a data packet to be sent to a destination host machine (e.g., another host machine (not shown) contained in another rack). The process then moves to step 1173, where a portion of the data packet's header is tagged (e.g., by an application running on the source host machine) to indicate the desired traffic type of the data packet and its corresponding handling. In some embodiments, the data packet's header may include a Type of Service (TOS) field that is one byte long. Two bits of the TOS field may be reserved for Explicit Congestion Notification (ECN) use, while the remaining six bits may be utilized for Differentiated Services Code Point (DSCP) use. Thus, the DSCP bits may be marked in a particular way to indicate the desired traffic type of the data packet and the corresponding treatment, for example, how an ECN packet of that traffic class is to be treated.

[0152] Having tagged a portion of the data packet's header (e.g., the DSCP bits of the TOS field), the process forwards the data packet by the source host machine over the communication path to the destination host machine in step 1175. For example, with reference to Figure 10, a source host machine, e.g., Host 1-B 1014, may forward the data packet to TOR1 switch 1016.

[0153] Exemplary Cloud Infrastructure Embodiments As mentioned above, infrastructure as a service (IaaS) is one particular type of cloud computing. IaaS may be configured to provide virtualized computing resources over a public network (e.g., the Internet). In an IaaS model, a cloud computing provider may host infrastructure components (e.g., servers, storage devices, network nodes (e.g., hardware), deployment software, platform virtualization (e.g., hypervisor layer), etc.). In some cases, an IaaS provider may offer various services (e.g., billing, monitoring, logging, security, load balancing, clustering, etc.) to accompany those infrastructure components. Thus, these services may be policy-driven, so that an IaaS user may implement policies to drive load balancing to maintain application availability and performance.

[0154] In some cases, IaaS customers may access resources and services over a wide area network (WAN), such as the Internet, and can use the cloud provider's services to install the remaining elements of their application stack. For example, a user can log into an IaaS platform to create virtual machines (VMs), install an operating system (OS) on each VM, deploy middleware such as databases, create storage buckets for workloads and backups, and even install enterprise software on the VMs. The customer can then use the provider's services to perform a variety of functions, including balancing network traffic, troubleshooting application issues, monitoring performance, managing disaster recovery, etc.

[0155] In most cases, the cloud computing model requires the participation of a cloud provider, which may be, but need not be, a third-party service that specializes in providing (e.g., offering, renting, selling) IaaS. An entity may choose to deploy a private cloud and become its own provider of infrastructure services.

[0156] In some examples, an IaaS deployment is the process of hooking up a new application or a new version of an application to a prepared application server or the like. This process may include the process of preparing the server (e.g., installing libraries, daemons, etc.). This process is often managed by the cloud provider below the hypervisor layer (e.g., server, storage, network hardware, and virtualization). Thus, the customer may be responsible for handling the deployment of the OS, middleware, and / or application (e.g., on top of self-service virtual machines (e.g., that may be spun up on demand)).

[0157] In some examples, IaaS provisioning may also refer to obtaining computers or virtual hosts for use and installing needed libraries or services on those computers or virtual hosts. In most cases, deployment does not include provisioning, which may need to be performed first.

[0158] In some cases, there are two distinct challenges in IaaS provisioning. First, there is the initial challenge of provisioning an initial set of infrastructure before anything can be run. Second, there is the challenge of evolving the existing infrastructure (e.g., adding new services, modifying services, removing services, etc.) after everything has been provisioned. In some cases, these two challenges may be addressed by allowing the configuration of the infrastructure to be defined declaratively. In other words, the infrastructure (e.g., which components are required and how those components interact) may be defined by one or more configuration files. In this way, the entire topology of the infrastructure (e.g., which resources depend on which resources and how each of those resources work together) may be described declaratively. In some cases, after the topology is defined, workflows may be generated that create and / or manage the various components described in the configuration files.

[0159] In some examples, the infrastructure may include many interconnected elements. For example, there may be one or more virtual private clouds (VPCs) (e.g., a configurable and / or shared, possibly on-demand pool of computing resources), also known as a core network. In some examples, there may be one or more security group rules provisioned to define how the security of the network is configured, and one or more virtual machines (VMs). Other infrastructure elements, such as load balancers, databases, etc., may be provisioned. The infrastructure may evolve over time as more infrastructure elements are desired and / or added.

[0160] In some cases, continuous deployment techniques may be employed to enable deployment of infrastructure code across various virtual computing environments. Additionally, the described techniques may enable infrastructure management within these environments. In some cases, a service team may write code that is desired to be deployed to one or more, but often many, different production environments (e.g., across various geographic locations, sometimes across the world). However, in some cases, the infrastructure to which the code is deployed must first be set up. In some cases, provisioning may be done manually, and provisioning tools may be utilized to provision resources and / or deployment tools may be utilized to deploy the code after the infrastructure is provisioned.

[0161] 12 is a block diagram 1200 illustrating an example pattern of an IaaS architecture, according to at least one embodiment. A service operator 1202 may be communicatively coupled to a secure host tenancy 1204, which may include a virtual cloud network (VCN) 1206 and a secure host subnet 1208. In some examples, the service operator 1202 may employ one or more client computing devices, which may be portable handheld devices (e.g., iPhone®, mobile phones, iPad®, computing tablets, personal digital assistants (PDAs)) or wearable devices (e.g., Google Glass® head-mounted displays) that are Internet, email, short message service (SMS), Blackberry®, or other communication protocol enabled, running software such as Microsoft Windows Mobile®, and / or various mobile operating systems such as iOS, Windows Phone, Android, BlackBerry 8, Palm OS, etc. Alternatively, the client computing devices can be general purpose personal computers, including, by way of example, personal and / or laptop computers running various versions of Microsoft Windows, Apple Macintosh, and / or Linux operating systems. The client computing devices can be workstation computers running any of a variety of commercially available UNIX or UNIX-like operating systems, including, but not limited to, various GNU / Linux operating systems, such as Google Chrome OS.Alternatively or additionally, the client computing device may be any other electronic device, such as a thin-client computer, an Internet-enabled gaming system (e.g., a Microsoft Xbox gaming console with or without a Kinect® gesture input device), and / or a personal messaging device, capable of communicating over a network accessible to VCN 1206 and / or the Internet.

[0162] VCN 1206 may include a local peering gateway (LPG) 1210, which may be communicatively coupled to a secure shell (SSH) VCN 1212 via an LPG 1210 included in SSH VCN 1212. SSH VCN 1212 may include an SSH subnet 1214, which may be communicatively coupled to a control plane VCN 1216 via an LPG 1210 included in control plane VCN 1216. SSH VCN 1212 may also be communicatively coupled to a data plane VCN 1218 via LPG 1210. The control plane VCN 1216 and the data plane VCN 1218 may be included in a service tenancy 1219, which may be owned and / or operated by the IaaS provider.

[0163] The control plane VCN 1216 may include a control plane demilitarized zone (DMZ) tier 1220 that serves as a perimeter network (e.g., a portion of an enterprise network between an enterprise intranet and an external network). Servers based in the DMZ may have limited responsibility and help keep security breaches contained. Additionally, the DMZ tier 1220 may include one or more load balancer (LB) subnets 1222, a control plane app tier 1224 that may include an app subnet 1226, a control plane data tier 1228 that may include a database (DB) subnet 1230 (e.g., a front-end DB subnet and / or a back-end DB subnet). LB subnet 1222 included in control plane DMZ tier 1220 can be communicatively coupled to app subnet 1226 and Internet gateway 1234 included in control plane app tier 1224 which may be included in control plane VCN 1216, and app subnet 1226 can be communicatively coupled to DB subnet 1230 as well as service gateway 1236 and network address translation (NAT) gateway 1238 included in control plane data tier 1228. Control plane VCN 1216 can include service gateway 1236 and NAT gateway 1238.

[0164] The control plane VCN 1216 can include a data plane mirrored app layer 1240 that can include an app subnet 1226. The app subnet 1226 included in the data plane mirrored app layer 1240 can include a virtual network interface controller (VNIC) 1242 that can run a compute instance 1244. The compute instance 1244 can communicatively couple the app subnet 1226 of the data plane mirrored app layer 1240 to the app subnet 1226 that can be included in the data plane app layer 1246.

[0165] The data plane VCN 1218 may include a data plane app layer 1246, a data plane DMZ layer 1248, and a data plane data layer 1250. The data plane DMZ layer 1248 may include a LB subnet 1222, which may be communicatively coupled to an app subnet 1226 of the data plane app layer 1246 and an Internet gateway 1234 of the data plane VCN 1218. The app subnet 1226 may be communicatively coupled to a service gateway 1236 of the data plane VCN 1218 and a NAT gateway 1238 of the data plane VCN 1218. The data plane data layer 1250 may also include a DB subnet 1230, which may be communicatively coupled to the app subnet 1226 of the data plane app layer 1246.

[0166] The Internet gateways 1234 of the control plane VCNs 1216 and of the data plane VCNs 1218 may be communicatively coupled to a metadata management service 1252, which may be communicatively coupled to the public Internet 1254. The public Internet 1254 may be communicatively coupled to NAT gateways 1238 of the control plane VCNs 1216 and of the data plane VCNs 1218. The service gateways 1236 of the control plane VCNs 1216 and of the data plane VCNs 1218 may be communicatively coupled to cloud services 1256.

[0167] In some examples, a service gateway 1236 in the control plane VCN 1216 or in the data plane VCN 1218 can make application programming interface (API) calls to cloud services 1256 without traversing the public Internet 1254. The API calls from the service gateway 1236 to the cloud services 1256 can be one-way: the service gateway 1236 can make the API call to the cloud services 1256 and the cloud services 1256 can send the requested data to the service gateway 1236. However, the cloud services 1256 may not initiate the API call to the service gateway 1236.

[0168] In some examples, secure host tenancy 1204 can be directly connected to service tenancy 1219 or may be otherwise separate. Secure host subnet 1208 can communicate with SSH subnet 1214 through LPG 1210, which may enable bidirectional communication on otherwise separate systems. Connecting secure host subnet 1208 to SSH subnet 1214 may give secure host subnet 1208 access to other entities in service tenancy 1219.

[0169] The control plane VCN 1216 may enable users of the service tenancy 1219 to configure or otherwise provision desired resources. The desired resources provisioned in the control plane VCN 1216 may be deployed or otherwise used in the data plane VCN 1218. In some examples, the control plane VCN 1216 may be separate from the data plane VCN 1218, and the data plane mirror app layer 1240 of the control plane VCN 1216 may communicate with the data plane app layer 1246 of the data plane VCN 1218 via a VNIC 1242, which may be included in the data plane mirror app layer 1240 and the data plane app layer 1246.

[0170] In some examples, a user or customer of the system may make a request, e.g., a create, read, update, or delete (CRUD) operation, via the public internet 1254, which may communicate the request to a metadata management service 1252. The metadata management service 1252 may communicate the request to the control plane VCN 1216 via an internet gateway 1234. The request may be received by a LB subnet 1222 included in the control plane DMZ layer 1220. The LB subnet 1222 may determine that the request is valid, and in response to this determination, the LB subnet 1222 may send the request to an app subnet 1226 included in the control plane app layer 1224. If the request is authenticated and the request requires a call to the public internet 1254, the call to the public internet 1254 may be sent to a NAT gateway 1238, which may make the call to the public internet 1254. Memory that may be desirable to be stored by the request may be stored within the DB subnet 1230.

[0171] In some examples, the data plane mirror app layer 1240 can facilitate direct communication between the control plane VCN 1216 and the data plane VCN 1218. For example, it may be desirable for changes, updates, or other suitable modifications to a configuration to be applied to resources included in the data plane VCN 1218. Through the VNIC 1242, the control plane VCN 1216 can communicate directly with the resources included in the data plane VCN 1218, thereby effecting changes, updates, or other suitable modifications to the configuration of the resources.

[0172] In some embodiments, the control plane VCN 1216 and the data plane VCN 1218 may be included in the service tenancy 1219. In this case, a user or customer of the system may not own or operate either the control plane VCN 1216 or the data plane VCN 1218. Instead, an IaaS provider may own or operate the control plane VCN 1216 and the data plane VCN 1218, both of which may be included in the service tenancy 1219. This embodiment may allow for network isolation that may prevent a user or customer from interacting with other users' resources or other customers' resources. This embodiment may also allow a user or customer of the system to store databases privately without having to rely on the public Internet 1254 for storage, which may not have a desirable level of security.

[0173] In another embodiment, the LB subnet 1222 included in the control plane VCN 1216 may be configured to receive signals from the service gateway 1236. In this embodiment, the control plane VCN 1216 and the data plane VCN 1218 may be configured to be called by the IaaS provider's customers without calling the public Internet 1254. The IaaS provider's customers may desire this embodiment because databases used by the customers may be stored in a service tenancy 1219 that may be controlled by the IaaS provider and may be isolated from the public Internet 1254.

[0174] 13 is a block diagram 1300 illustrating another example pattern of an IaaS architecture, according to at least one embodiment. A service operator 1302 (e.g., service operator 1202 of FIG. 12) may be communicatively coupled to a secure host tenancy 1304 (e.g., secure host tenancy 1204 of FIG. 12), which may include a virtual cloud network (VCN) 1306 (e.g., VCN 1206 of FIG. 12) and a secure host subnet 1308 (e.g., secure host subnet 1208 of FIG. 12). The VCN 1306 may include a local peering gateway (LPG) 1310 (e.g., LPG 1210 of FIG. 12), which may be communicatively coupled to an SSH VCN 1312 (e.g., SSH VCN 1212 of FIG. 12) via an LPG 1310 included in a secure shell (SSH) VCN 1312. SSH VCN 1312 can include an SSH subnet 1314 (e.g., SSH subnet 1214 in FIG. 12), which can be communicatively coupled to a control plane VCN 1316 (e.g., control plane VCN 1216 in FIG. 12) via an LPG 1310 included in the control plane VCN 1316. The control plane VCN 1316 can be included in a service tenancy 1319 (e.g., service tenancy 1219 in FIG. 12), and the data plane VCN 1318 (e.g., data plane VCN 1218 in FIG. 12) can be included in a customer tenancy 1321, which can be owned or operated by a user or customer of the system.

[0175] The control plane VCN 1316 may include a control plane DMZ tier 1320 (e.g., control plane DMZ tier 1220 of FIG. 12 ) that may include a LB subnet 1322 (e.g., LB subnet 1222 of FIG. 12 ), a control plane app tier 1324 (e.g., control plane app tier 1224 of FIG. 12 ) that may include an app subnet 1326 (e.g., app subnet 1226 of FIG. 12 ), and a control plane data tier 1328 (e.g., control plane data tier 1228 of FIG. 12 ) that may include a database (DB) subnet 1330 (e.g., similar to the database (DB) subnet 1230 of FIG. 12 ). The LB subnet 1322 included in the control plane DMZ tier 1320 can be communicatively coupled to an app subnet 1326 and an Internet gateway 1334 (e.g., Internet gateway 1234 of FIG. 12 ) included in a control plane app tier 1324 that may be included in the control plane VCN 1316, and the app subnet 1326 can be communicatively coupled to a DB subnet 1330 and a service gateway 1336 (e.g., service gateway of FIG. 12 ) and a network address translation (NAT) gateway 1338 (e.g., NAT gateway 1238 of FIG. 12 ) included in the control plane data tier 1328. The control plane VCN 1316 can include the service gateway 1336 and the NAT gateway 1338.

[0176] The control plane VCN 1316 can include a data plane mirror app layer 1340 (e.g., data plane mirror app layer 1240 of FIG. 12 ), which can include an app subnet 1326. The app subnet 1326 included in the data plane mirror app layer 1340 can include a virtual network interface controller (VNIC) 1342 (e.g., VNIC 1242 ) that can run a compute instance 1344 (e.g., similar to compute instance 1244 of FIG. 12 ). The compute instance 1344 can facilitate communication between the app subnet 1326 of the data plane mirror app layer 1340 and the app subnet 1326 that can be included in the data plane app layer 1346 (e.g., data plane app layer 1246 of FIG. 12 ) via the VNIC 1342 included in the data plane mirror app layer 1340 and the VNIC 1342 included in the data plane app layer 1346.

[0177] The Internet gateway 1334 included in the control plane VCN 1316 may be communicatively coupled to a metadata management service 1352 (e.g., metadata management service 1252 of FIG. 12), which may be communicatively coupled to a public Internet 1354 (e.g., public Internet 1254 of FIG. 12). The public Internet 1354 may be communicatively coupled to a NAT gateway 1338 included in the control plane VCN 1316. The service gateway 1336 included in the control plane VCN 1316 may be communicatively coupled to cloud services 1356 (e.g., cloud services 1256 of FIG. 12).

[0178] In some examples, the data plane VCN 1318 may be included in the customer's tenancy 1321. In this case, the IaaS provider may provide a control plane VCN 1316 for each customer, and the IaaS provider may configure a unique compute instance 1344 for each customer that is included in the service tenancy 1319. Each compute instance 1344 may enable communication between the control plane VCN 1316 included in the service tenancy 1319 and the data plane VCN 1318 included in the customer's tenancy 1321. The compute instance 1344 may enable resources provisioned in the control plane VCN 1316 included in the service tenancy 1319 to be deployed or otherwise used in the data plane VCN 1318 included in the customer's tenancy 1321.

[0179] In another example, an IaaS provider customer may have a database that resides in the customer's tenancy 1321. In this example, the control plane VCN 1316 may include a data plane mirror app layer 1340, which may include an app subnet 1326. The data plane mirror app layer 1340 may reside in the data plane VCN 1318, but the data plane mirror app layer 1340 may not reside in the data plane VCN 1318. That is, the data plane mirror app layer 1340 may have access to the customer's tenancy 1321, but the data plane mirror app layer 1340 may not reside in the data plane VCN 1318 and may not be owned or operated by the IaaS provider customer. The data plane mirror app layer 1340 may be configured to make calls to the data plane VCN 1318, but may not be configured to make calls to any entities included in the control plane VCN 1316. A customer may desire to deploy or otherwise use resources in the data plane VCN 1318 that have been provisioned in the control plane VCN 1316, and the data plane mirror app layer 1340 can facilitate the desired deployment or other use of the customer's resources.

[0180] In some embodiments, the IaaS provider's customer can apply filters to the data plane VCN 1318. In this embodiment, the customer can determine which data plane VCNs 1318 are accessible, and the customer can limit access from the data plane VCN 1318 to the public Internet 1354. The IaaS provider may not be able to apply filters or otherwise control the access of the data plane VCN 1318 to any external networks or databases. Applying filters and controls by the customer to the data plane VCN 1318 contained in the customer's tenancy 1321 can help isolate the data plane VCN 1318 from other customers and from the public Internet 1354.

[0181] In some embodiments, cloud services 1356 may be called by service gateway 1336 to access services that may not reside on public internet 1354, control plane VCN 1316, or data plane VCN 1318. The connection between cloud services 1356 and control plane VCN 1316 or data plane VCN 1318 may not be up and running or continuous. Cloud services 1356 may reside in different networks owned or operated by an IaaS provider. Cloud services 1356 may be configured to receive calls from service gateway 1336 and may not be configured to receive calls from public internet 1354. Some cloud services 1356 may be isolated from other cloud services 1356, and control plane VCN 1316 may be isolated from cloud services 1356 that may not reside in the same region as control plane VCN 1316. For example, control plane VCN 1316 may be located in "region 1," and a cloud service "deployment 12" may be located in region 1 and "region 2." When a call is made to deployment 12 by a service gateway 1336 included in control plane VCN 1316 located in region 1, the call may be sent to deployment 12 in region 1. In this example, control plane VCN 1316, or deployment 12 in region 1, may not be communicatively coupled to or otherwise in communication with deployment 12 in region 2.

[0182] 14 is a block diagram 1400 illustrating another example pattern of an IaaS architecture, according to at least one embodiment. A service operator 1402 (e.g., service operator 1202 of FIG. 12) may be communicatively coupled to a secure host tenancy 1404 (e.g., secure host tenancy 1204 of FIG. 12), which may include a virtual cloud network (VCN) 1406 (e.g., VCN 1206 of FIG. 12) and a secure host subnet 1408 (e.g., secure host subnet 1208 of FIG. 12). The VCN 1406 may include an LPG 1410 (e.g., LPG 1210 of FIG. 12), which may be communicatively coupled to an SSH VCN 1412 (e.g., SSH VCN 1212 of FIG. 12) via an LPG 1410 included in the SSH VCN 1412. SSH VCN 1412 can include an SSH subnet 1414 (e.g., SSH subnet 1214 of FIG. 12), which can be communicatively coupled to a control plane VCN 1416 (e.g., control plane VCN 1216 of FIG. 12) via an LPG 1410 included in control plane VCN 1416, and to a data plane VCN 1418 (e.g., data plane 1218 of FIG. 12) via an LPG 1410 included in data plane VCN 1418. Control plane VCN 1416 and data plane VCN 1418 can be included in service tenancy 1419 (e.g., service tenancy 1219 of FIG. 12).

[0183] The control plane VCN 1416 may include a control plane DMZ tier 1420 (e.g., control plane DMZ tier 1220 of FIG. 12 ) that may include a load balancer (LB) subnet 1422 (e.g., LB subnet 1222 of FIG. 12 ), a control plane app tier 1424 (e.g., control plane app tier 1224 of FIG. 12 ) that may include an app subnet 1426 (e.g., similar to app subnet 1226 of FIG. 12 ), and a control plane data tier 1428 (e.g., control plane data tier 1228 of FIG. 12 ) that may include a DB subnet 1430. The LB subnet 1422 included in the control plane DMZ tier 1420 can be communicatively coupled to an app subnet 1426 included in a control plane app tier 1424 that may be included in the control plane VCN 1416, and to an Internet gateway 1434 (e.g., Internet gateway 1234 of FIG. 12), which can be communicatively coupled to a DB subnet 1430 included in a control plane data tier 1428, as well as to a service gateway 1436 (e.g., service gateway of FIG. 12) and a network address translation (NAT) gateway 1438 (e.g., NAT gateway 1238 of FIG. 12). The control plane VCN 1416 can include the service gateway 1436 and the NAT gateway 1438.

[0184] The data plane VCN 1418 may include a data plane app layer 1446 (e.g., data plane app layer 1246 of FIG. 12), a data plane DMZ layer 1448 (e.g., data plane DMZ layer 1248 of FIG. 12), and a data plane data layer 1450 (e.g., data plane data layer 1250 of FIG. 12). The data plane DMZ layer 1448 may include a trusted app subnet 1460 and an untrusted app subnet 1462 of the data plane app layer 1446 and a LB subnet 1422 that may be communicatively coupled to an Internet gateway 1434 included in the data plane VCN 1418. The trusted app subnet 1460 may be communicatively coupled to a service gateway 1436 included in the data plane VCN 1418, a NAT gateway 1438 included in the data plane VCN 1418, and a DB subnet 1430 included in the data plane data layer 1450. The untrusted app subnet 1462 may be communicatively coupled to a service gateway 1436 included in the data plane VCN 1418 and to a DB subnet 1430 included in the data plane data layer 1450. The data plane data layer 1450 may include a DB subnet 1430 that may be communicatively coupled to a service gateway 1436 included in the data plane VCN 1418.

[0185] The untrusted app subnet 1462 may include one or more primary VNICs 1464(1)-(N) that may be communicatively coupled to tenant virtual machines (VMs) 1466(1)-(N). Each tenant VM 1466(1)-(N) may be communicatively coupled to a respective app subnet 1467(1)-(N) that may be included in a respective container egress VCN 1468(1)-(N) that may be included in a respective customer tenancy 1470(1)-(N). Each secondary VNIC 1472(1)-(N) may facilitate communication between the untrusted app subnet 1462 included in the data plane VCN 1418 and the app subnet included in the container egress VCN 1468(1)-(N). Each container egress VCN 1468(1)-(N) may include a NAT gateway 1438 that may be communicatively coupled to the public Internet 1454 (e.g., public Internet 1254 of FIG. 12).

[0186] An Internet gateway 1434 included in the control plane VCN 1416 and included in the data plane VCN 1418 may be communicatively coupled to a metadata management service 1452 (e.g., metadata management system 1252 of FIG. 12 ), which may be communicatively coupled to the public Internet 1454. The public Internet 1454 may be communicatively coupled to a NAT gateway 1438 included in the control plane VCN 1416 and included in the data plane VCN 1418. A service gateway 1436 included in the control plane VCN 1416 and included in the data plane VCN 1418 may be communicatively coupled to cloud services 1456.

[0187] In some embodiments, data plane VCN 1418 may be integrated with customer tenancies 1470. This integration may be useful or desirable for an IaaS provider's customers in some cases, such as when they may want support when executing code. A customer may provide code for execution that may be disruptive, may communicate with other customers' resources, or may otherwise cause undesirable effects. In response, the IaaS provider may determine whether to execute the code provided to the IaaS provider by the customer.

[0188] In some examples, a customer of an IaaS provider may grant temporary network access to the IaaS provider and request the ability to connect to the data plane app layer 1446. Code to perform this function may be executed in VMs 1466(1)-(N), which may not be configured to run elsewhere on the data plane VCN 1418. Each VM 1466(1)-(N) may be connected to one customer's tenancy 1470. Each container 1471(1)-(N) contained in VMs 1466(1)-(N) may be configured to execute code. In this case, there may be a double isolation (e.g., container 1471(1)-(N) executing code may be contained in at least VM 1466(1)-(N) that is contained in untrusted app subnet 1462), which may help prevent incorrect or otherwise undesirable code from damaging the IaaS provider's network or damaging a different customer's network. Container 1471(1)-(N) may be communicatively coupled to customer tenancy 1470 and may be configured to send or receive data to or from customer tenancy 1470. Container 1471(1)-(N) may not be configured to send or receive data to or from any other entity in data plane VCN 1418. Upon completion of code execution, IaaS provider may kill or otherwise destroy container 1471(1)-(N).

[0189] In some embodiments, trusted app subnet 1460 may execute code that may be owned or operated by the IaaS provider. In this embodiment, trusted app subnet 1460 may be communicatively coupled to DB subnet 1430 and may be configured to perform CRUD operations within DB subnet 1430. Untrusted app subnet 1462 may be communicatively coupled to DB subnet 1430, but in this embodiment, untrusted app subnet 1462 may be configured to perform read operations within DB subnet 1430. Containers 1471(1)-(N) capable of executing code from the customer, which may be included in each customer's VMs 1466(1)-(N), may not be communicatively coupled to DB subnet 1430.

[0190] In other embodiments, the control plane VCN 1416 and the data plane VCN 1418 may not be directly communicatively coupled. In this embodiment, there may not be direct communication between the control plane VCN 1416 and the data plane VCN 1418. However, communication may occur indirectly by at least one method. The LPG 1410 may be established by an IaaS provider and may facilitate communication between the control plane VCN 1416 and the data plane VCN 1418. In another example, the control plane VCN 1416 or the data plane VCN 1418 may make a call to a cloud service 1456 via a service gateway 1436. For example, a call from the control plane VCN 1416 to the cloud service 1456 may include a request for a service that may communicate with the data plane VCN 1418.

[0191] FIG. 15 is a block diagram 1500 illustrating another example pattern of an IaaS architecture, according to at least one embodiment. A service operator 1502 (e.g., service operator 1202 of FIG. 12) may be communicatively coupled to a secure host tenancy 1504 (e.g., secure host tenancy 1204 of FIG. 12), which may include a virtual cloud network (VCN) 1506 (e.g., VCN 1206 of FIG. 12) and a secure host subnet 1508 (e.g., secure host subnet 1208 of FIG. 12). The VCN 1506 may include an LPG 1510 (e.g., LPG 1210 of FIG. 12), which may be communicatively coupled to an SSH VCN 1512 (e.g., SSH VCN 1212 of FIG. 12) via an LPG 1510 included in the SSH VCN 1512. SSH VCN 1512 can include an SSH subnet 1514 (e.g., SSH subnet 1214 in FIG. 12), which can be communicatively coupled to a control plane VCN 1516 (e.g., control plane VCN 1216 in FIG. 12) via an LPG 1510 included in control plane VCN 1516, and to a data plane VCN 1518 (e.g., data plane 1218 in FIG. 12) via an LPG 1510 included in data plane VCN 1518. Control plane VCN 1516 and data plane VCN 1518 can be included in service tenancy 1519 (e.g., service tenancy 1219 in FIG. 12).

[0192] The control plane VCN 1516 may include a control plane DMZ layer 1520 (e.g., control plane DMZ layer 1220 of FIG. 12) that may include a LB subnet 1522 (e.g., LB subnet 1222 of FIG. 12), a control plane app layer 1524 (e.g., control plane app layer 1224 of FIG. 12) that may include an app subnet 1526 (e.g., app subnet 1226 of FIG. 12), and a control plane data layer 1528 (e.g., control plane data layer 1228 of FIG. 12) that may include a DB subnet 1530 (e.g., DB subnet 1430 of FIG. 14). The LB subnet 1522 included in the control plane DMZ tier 1520 can be communicatively coupled to an app subnet 1526 included in a control plane app tier 1524 that may be included in the control plane VCN 1516, and to an Internet gateway 1534 (e.g., Internet gateway 1234 of FIG. 12), which can be communicatively coupled to a DB subnet 1530 included in a control plane data tier 1528, as well as to a service gateway 1536 (e.g., service gateway of FIG. 12) and a network address translation (NAT) gateway 1538 (e.g., NAT gateway 1238 of FIG. 12). The control plane VCN 1516 can include the service gateway 1536 and the NAT gateway 1538.

[0193] The data plane VCN 1518 can include a data plane app layer 1546 (e.g., data plane app layer 1246 of FIG. 12), a data plane DMZ layer 1548 (e.g., data plane DMZ layer 1248 of FIG. 12), and a data plane data layer 1550 (e.g., data plane data layer 1250 of FIG. 12). The data plane DMZ layer 1548 can include a trusted app subnet 1560 (e.g., trusted app subnet 1460 of FIG. 14) and an untrusted app subnet 1562 (e.g., untrusted app subnet 1462 of FIG. 14) of the data plane app layer 1546, as well as a LB subnet 1522 that can be communicatively coupled to an Internet gateway 1534 included in the data plane VCN 1518. The trusted app subnet 1560 may be communicatively coupled to a service gateway 1536 included in the data plane VCN 1518, a NAT gateway 1538 included in the data plane VCN 1518, and a DB subnet 1530 included in the data plane data layer 1550. The untrusted app subnet 1562 may be communicatively coupled to a service gateway 1536 included in the data plane VCN 1518, and a DB subnet 1530 included in the data plane data layer 1550. The data plane data layer 1550 may include a DB subnet 1530 that may be communicatively coupled to a service gateway 1536 included in the data plane VCN 1518.

[0194] The untrusted app subnet 1562 may include primary VNICs 1564(1)-(N) that may be communicatively coupled to tenant virtual machines (VMs) 1566(1)-(N) that reside within the untrusted app subnet 1562. Each tenant VM 1566(1)-(N) may execute code within a respective container 1567(1)-(N) and may be communicatively coupled to an app subnet 1526 that may be included in a data plane app layer 1546 that may be included in a container egress VCN 1568. Each secondary VNIC 1572(1)-(N) may facilitate communication between the untrusted app subnet 1562 included in the data plane VCN 1518 and the app subnet included in the container egress VCN 1568. The container egress VCN may include a NAT gateway 1538 that may be communicatively coupled to the public Internet 1554 (e.g., public Internet 1254 of FIG. 12).

[0195] An Internet gateway 1534 included in the control plane VCN 1516 and included in the data plane VCN 1518 may be communicatively coupled to a metadata management service 1552 (e.g., metadata management system 1252 of FIG. 12 ), which may be communicatively coupled to the public Internet 1554. The public Internet 1554 may be communicatively coupled to a NAT gateway 1538 included in the control plane VCN 1516 and included in the data plane VCN 1518. A service gateway 1536 included in the control plane VCN 1516 and included in the data plane VCN 1518 may be communicatively coupled to cloud services 1556.

[0196] In some examples, the pattern illustrated by the architecture of block diagram 1500 of FIG. 15 may be considered an exception to the pattern illustrated by the architecture of block diagram 1400 of FIG. 14 and may be desirable for a customer of an IaaS provider when the IaaS provider cannot directly communicate with the customer (e.g., disconnected region). Each container 1567(1)-(N) contained in a VM 1566(1)-(N) per customer may be accessed in real time by the customer. The containers 1567(1)-(N) may be configured to make calls to each secondary VNIC 1572(1)-(N) contained in the app subnet 1526 of the data plane app tier 1546 that may be contained in a container egress VCN 1568. The secondary VNIC 1572(1)-(N) may send the call to a NAT gateway 1538, which may send the call to the public Internet 1554. In this example, containers 1567(1)-(N) that may be accessed in real time by a customer may be isolated from control plane VCN 1516 and may be isolated from other entities included in data plane VCN 1518. Containers 1567(1)-(N) may be isolated from other customer resources.

[0197] In another example, a customer may use container 1567(1)-(N) to invoke cloud service 1556. In this example, the customer may execute code in container 1567(1)-(N) that requests a service from cloud service 1556. Container 1567(1)-(N) may send the request to secondary VNIC 1572(1)-(N), which may send the request to a NAT gateway, which may send the request to public Internet 1554. Public Internet 1554 may send the request via Internet gateway 1534 to LB subnet 1522, which is included in control plane VCN 1516. In response to determining that the request is valid, LB subnet 1526 may send the request to app subnet 1526, which may send the request to cloud service 1556 via service gateway 1536.

[0198] It should be understood that the IaaS architectures 1200, 1300, 1400, 1500 depicted in the figures may include components other than those depicted. Additionally, the embodiments depicted in the figures are merely some examples of cloud infrastructure systems that may incorporate embodiments of the present disclosure. In some other embodiments, the IaaS systems may include more or fewer components than those depicted in the figures, may combine two or more components, or may have a different configuration or arrangement of components.

[0199] In one embodiment, the IaaS system described herein may include an offering of a suite of application, middleware, and database services that are delivered to customers in a self-service, subscription-based, elastically scalable, reliable, highly available, and secure manner. An example of such an IaaS system is Oracle Cloud Infrastructure (OCI) offered by the present assignee.

[0200] 16 illustrates an exemplary computer system 1600 upon which various embodiments may be implemented. The system 1600 may be used to implement any of the computer systems described above. As shown in the figure, the computer system 1600 includes a processing unit 1604 that communicates with a number of peripheral subsystems via a bus subsystem 1602. These peripheral subsystems may include a processing acceleration unit 1606, an I / O subsystem 1608, a storage subsystem 1618, and a communication subsystem 1624. The storage subsystem 1618 includes a tangible computer-readable storage medium 1622 and a system memory 1610.

[0201] Bus subsystem 1602 provides a mechanism for allowing the various components and subsystems of computer system 1600 to communicate with each other as intended. Although bus subsystem 1602 is shown diagrammatically as a single bus, alternative embodiments of the bus subsystem may utilize multiple buses. Bus subsystem 1602 may be any of several types of bus structures, including a memory bus or memory controller, a peripheral bus, and a local bus using any of a variety of bus architectures. For example, such architectures may include a Peripheral Component Interconnect (PCI) bus, which may be implemented as an Industry Standard Architecture (ISA) bus, a Micro Channel Architecture (MCA) bus, an Enhanced ISA (EISA) bus, a Video Electronics Standards Association (VESA) local bus, and a mezzanine bus manufactured to the IEEE P1386.1 standard.

[0202] Processing unit 1604, which may be implemented as one or more integrated circuits (e.g., conventional microprocessors or microcontrollers), controls the operation of computer system 1600. One or more processors may be included in processing unit 1604. These processors may include single-core processors or multi-core processors. In an embodiment, processing unit 1604 may be implemented as one or more independent processing units 1632 and / or 1634, with a single-core processor or a multi-core processor included in each processing unit. In other embodiments, processing unit 1604 may be implemented as a quad-core processing unit formed by integrating two dual-core processors into a single chip.

[0203] In various embodiments, the processing unit 1604 may execute various programs in response to program code and may maintain multiple simultaneously executing programs or processes. At any particular time, some or all of the program code being executed may reside on the processor 1604 and / or on the storage subsystem 1618. Through appropriate programming, the processor 1604 may provide various functions as previously discussed. The computer system 1600 may further include a processing acceleration unit 1606, which may include a digital signal processor (DSP), a special purpose processor, and / or the like.

[0204] The I / O subsystem 1608 may include user interface input devices and user interface output devices. User interface input devices may include a keyboard, a pointing device such as a mouse or trackball, a touchpad or touch screen integrated into a display, a scroll wheel, a click wheel, a dial, a button, a switch, a keypad, a voice input device with a voice command recognition system, a microphone, and other types of input devices. User interface input devices may include motion detection devices and / or gesture recognition devices, such as, for example, a Microsoft Kinect® motion sensor that allows a user to control and interact with an input device, such as a Microsoft Xbox® 360 game controller, via a natural user interface using gestures and spoken commands. User interface input devices may include eye gesture recognition devices, such as a Google Glass® blink detector that detects a user's eye activity (e.g., "blinking" when taking a picture and / or selecting a menu) and translates the eye gesture as input to an input device (e.g., Google Glass®). Additionally, the user interface input devices may include a voice recognition detection device that allows a user to interact with a voice recognition system (eg, the Siri® navigator) via voice commands.

[0205] User interface input devices may include, but are not limited to, three dimensional (3D) mice, joysticks or pointing sticks, game pads, and graphic tablets, as well as audio / visual devices such as speakers, digital cameras, digital video cameras, portable media players, webcams, image scanners, fingerprint scanners, barcode readers 3D scanners, 3D printers, laser range finders, and eye tracking devices. Additionally, user interface input devices may include medical imaging input devices, such as, for example, computed tomography, magnetic resonance imaging, position emission tomography, and medical ultrasound devices. User interface input devices may include audio input devices, such as, for example, MIDI keyboards, digital musical instruments, and the like.

[0206] User interface output devices may include non-visual displays such as a display subsystem, indicator lights, or audio output devices. The display subsystem may be a flat panel device such as a flat panel device using a cathode ray tube (CRT), a liquid crystal display (LCD) or a plasma display, a projection device, a touch screen, etc. In general, use of the term "output device" is intended to include all possible types of devices and mechanisms for outputting information from computer system 1600 to a user or to another computer. For example, user interface output devices may include, but are not limited to, various display devices that visually convey textual, graphical, and audio / video information, such as monitors, printers, speakers, headphones, navigation systems, plotters, audio output devices, and modems.

[0207] Computer system 1600 may include a storage subsystem 1618 that includes the software elements shown as presently residing in system memory 1610. System memory 1610 may store program instructions readable and executable by processing unit 1604, as well as data generated during the execution of these programs.

[0208] Depending on the configuration and type of computer system 1600, the system memory 1610 may be volatile (such as random-access memory (RAM)) and / or non-volatile (such as read-only memory (ROM), flash memory, etc.). RAM typically contains data and / or program modules that are immediately accessible to and / or currently being operated on and executed by the processing unit 1604. In some implementations, the system memory 1610 may include a number of different types of memory, such as static random access memory (SRAM) or dynamic random access memory (DRAM). In some implementations, a basic input / output system (BIOS), containing the basic routines that help to transfer information between elements within the computer system 1600, such as during start-up, may typically be stored in ROM. By way of example and not limitation, system memory 1610 also illustrates application programs 1612, program data 1614, and operating system 1616, which may include client applications, web browsers, mid-tier applications, relational database management systems (RDBMS), and the like.Examples of operating systems 1616 may include various versions of Microsoft Windows®, Apple Macintosh®, and / or Linux operating systems, various commercially available UNIX® or UNIX-like operating systems (including, but not limited to, various GNU / Linux operating systems, Google Chrome® OS, etc.), and / or mobile operating systems such as iOS, Windows® Phone, Android® OS, BlackBerry® 16 OS, and Palm® OS operating systems.

[0209] The storage subsystem 1618 may provide a tangible computer-readable storage medium for storing the basic programming and data configurations that provide the functionality of some embodiments. Software (programs, code modules, instructions) that, when executed by a processor, provide the aforementioned functionality may be stored in the storage subsystem 1618. These software modules or instructions may be executed by the processing unit 1604. The storage subsystem 1618 may provide a repository for storing data used in accordance with the present disclosure.

[0210] Storage subsystem 1600 may include computer readable storage medium reader 1620, which may be further connected to computer readable storage medium 1622. In combination with system memory 1610, optionally together, computer readable storage medium 1622 may comprehensively represent remote, local, fixed, and / or removable storage media as well as storage media for temporarily and / or more permanently containing, storing, transmitting, and retrieving computer readable information.

[0211] The computer readable storage medium 1622 containing the code or portions of code may include any suitable medium known or used in the art, including, but not limited to, storage media and communication media, such as volatile and non-volatile, removable and non-removable media, implemented in any manner or technology for storing and / or transmitting information. The computer readable storage medium 1622 may include tangible computer readable storage media, such as RAM, ROM, electronically erasable programmable ROM (EEPROM), flash memory or other memory technology, CD-ROM, digital versatile disk (DVD), or other optical storage, magnetic cassettes, magnetic tape, magnetic disk storage, or other magnetic storage devices, or other tangible computer readable media. The computer readable storage medium 1622 may also include non-tangible computer readable media, such as data signals, data transmissions, or any other medium that may be used to transmit the desired information and that may be accessed by the computing system 1600.

[0212] By way of example, computer readable storage media 1622 may include hard disk drives that read from or write to non-removable, non-volatile magnetic media, magnetic disk drives that read from or write to removable, non-volatile magnetic disks, and optical disk drives that read from or write to removable, non-volatile optical disks, such as CD ROMs, DVDs, and Blu-ray disks, or other optical media. Computer readable storage media 1622 may include, but are not limited to, Zip drives, flash memory cards, universal serial bus (USB) flash drives, secure digital (SD) cards, DVD disks, digital video tapes, and the like. The computer-readable storage media 1622 may include solid-state drives (SSDs) based on non-volatile memory such as flash memory-based SSDs, enterprise flash drives, solid-state ROMs, solid-state RAM, dynamic RAM, static RAM, DRAM-based SSDs, volatile memory-based SSDs such as magneto resistive RAM (MRAM) SSDs, and hybrid SSDs using a combination of DRAM and flash memory-based SSDs. The disk drives and associated computer-readable media may provide non-volatile storage of computer readable instructions, data structures, program modules, and other data for the computer system 1600.

[0213] The communications subsystem 1624 provides an interface to other computer systems and networks. The communications subsystem 1624 serves as an interface for receiving data from and transmitting data to other systems of the computer system 1600. For example, the communications subsystem 1624 may enable the computer system 1600 to connect to one or more devices via the Internet. In some embodiments, the communications subsystem 1624 may include radio frequency (RF) transceiver components for accessing wireless voice and / or data networks (e.g., using cellular technology, advanced data network technologies such as 3G, 4G, or EDGE (enhanced data rates for global evolution), WiFi (IEEE 802.11 family of standards, or other mobile communications technologies, or any combination thereof), global positioning system (GPS) receiver components, and / or other components. In some embodiments, the communications subsystem 1624 may provide a wired network connection (e.g., Ethernet) in addition to or instead of a wireless interface.

[0214] In some embodiments, the communications subsystem 1624 may receive incoming communications in the form of structured and / or unstructured data feeds 1626, event streams 1628, event updates 1630, etc. on behalf of one or more users who may use the computer system 1600.

[0215] By way of example, the communications subsystem 1624 may be configured to receive data feeds 1626 in real time from users of social networks and / or other communications services, such as Twitter® feeds, Facebook® updates, web feeds, such as Rich Site Summary (RSS) feeds, and / or real-time updates from one or more third party sources.

[0216] Additionally, the communications subsystem 1624 may be configured to receive data in the form of a continuous data stream, which may include an event stream 1628 of real-time events and / or event updates 1630 that may be continuous in nature or bounded without an explicit end. Examples of applications that generate continuous data may include, for example, sensor data applications, financial tickers, network performance measurement tools (e.g., network monitoring and traffic management applications), clickstream analysis tools, automobile traffic monitoring, and the like.

[0217] The communications subsystem 1624 may be configured to output structured and / or unstructured data feeds 1626, event streams 1628, event updates 1630, etc. to one or more databases that can be in communication with one or more streaming data source computers coupled to the computer system 1600.

[0218] The computer system 1600 can be one of a variety of types, including a handheld portable device (e.g., an iPhone® mobile phone, an iPad® computing tablet, a PDA), a wearable device (e.g., a Google Glass® head mounted display), a PC, a workstation, a mainframe, a ticket machine, a server rack, or any other data processing system.

[0219] Due to the ever-changing nature of computers and networks, the description of the computer system 1600 shown in the figure is intended to be merely a specific example. Many other configurations are possible, including more or fewer components than the system shown in the figure. For example, customized hardware may be used and / or particular elements may be implemented in hardware, firmware, software (including applets), or a combination thereof. Furthermore, connections to other computing devices, such as network input / output devices, may be employed. Based on the disclosure and teachings provided herein, one of ordinary skill in the art will appreciate other ways and / or manners for implementing various embodiments.

[0220] Although specific embodiments have been described, various modifications, variations, alternative constructions, and equivalents are encompassed within the scope of the disclosure. The embodiments are not limited to operation in one particular data processing environment, but can freely operate in multiple data processing environments. Furthermore, while the embodiments have been described using a particular sequence of transactions and steps, it should be apparent to one skilled in the art that the scope of the disclosure is not limited to the sequence of transactions and steps described. Various features and aspects of the foregoing embodiments may be used individually or together.

[0221] Furthermore, while embodiments have been described using a particular combination of hardware and software, it should be recognized that other combinations of hardware and software are within the scope of the present disclosure. Embodiments may be implemented in hardware alone, or in software alone, or using a combination thereof. Various processes described herein may be performed on the same processor or different processors in any combination. Thus, when a component or module is described as being configured to perform an operation, such configuration may be realized, for example, by designing an electronic circuit to perform the operation, by programming a programmable electronic circuit (such as a microprocessor) to perform the operation, or by any combination thereof. Processes may communicate using a variety of techniques, including, but not limited to, conventional techniques for inter-process communication, and different pairs of processes may use different techniques, or the same pair of processes may use different techniques at different times.

[0222] Accordingly, the specification and drawings should be regarded as illustrative rather than limiting in any sense. However, it is apparent that additions, subtractions, deletions, and other modifications and changes may be made to the specification and drawings without departing from the broader spirit and scope as set forth in the claims. Thus, although certain disclosed embodiments have been described, they are not intended to be limiting. Various modifications and equivalents are within the scope of the appended claims.

[0223] The use of the terms "a" and "an" and "the" and similar referents in the context of describing the disclosed embodiments (particularly in the context of the appended claims) should be construed to cover both the singular and the plural, unless otherwise indicated herein or clearly contradicted by context. The terms "comprising," "having," "including," and "containing" should be construed as open-ended (i.e., meaning "including, but not limited to") terms, unless otherwise noted. The term "connected" should be construed as partially or completely contained within, connected to, or joined together, even if there is something intervening. The recitation of ranges of values ​​herein is intended merely to serve as a shorthand method of individually referring to each separate value included in the range, unless otherwise indicated herein, and each separate value is incorporated herein as if it were individually recited herein. All methods described herein can be performed in any suitable order, unless otherwise indicated herein or otherwise clearly contradicted by context. The use of any and all examples or exemplary language (e.g., "etc.") provided herein is intended merely to better illuminate the embodiments and does not impose limitations on the scope of the disclosure unless specifically claimed. No language in the specification should be construed as indicating any non-claimed element as essential to the practice of the disclosure.

[0224] Disjunctive language, such as the phrase "at least one of X, Y, or Z," is generally intended to be understood within the context as being used to state that an item, condition, etc. may be either X, Y, or Z, or any combination thereof (e.g., X, Y, and / or Z), unless expressly stated otherwise. Thus, such disjunctive language is generally not intended to, and should not, imply that an embodiment requires that at least one of X, at least one of Y, or at least one of Z, respectively, be present.

[0225] Preferred embodiments of the present disclosure are described herein, including the best mode known for carrying out the present disclosure. Variations of such preferred embodiments may become apparent to those skilled in the art upon reading the foregoing description. Those skilled in the art should be able to adopt such variations as necessary, and the present disclosure may be practiced other than as specifically described herein. Accordingly, the present disclosure includes all modifications and equivalents of the subject matter recited in the claims appended hereto as permitted by applicable law. Moreover, any combination of the above-described elements in all possible variations of the embodiments is encompassed by the present disclosure, unless otherwise indicated herein.

[0226] All references cited in this specification, including publications, patent applications, and patents, are hereby incorporated by reference to the same extent as if each reference was individually indicated to be incorporated by reference and was set forth in its entirety herein.

[0227] Although aspects of the disclosure have been described in the foregoing specification with reference to specific embodiments thereof, those skilled in the art will recognize that the disclosure is not limited thereto. Various features and aspects of the foregoing disclosure may be used individually or together. Moreover, the embodiments may be utilized in any number of environments and applications beyond those described herein without departing from the broader spirit and scope of the specification. Thus, the specification and drawings should be regarded as illustrative rather than restrictive.< / realm>

Claims

1. 1. A method comprising: a network device in a communication path between a source host machine and a destination host machine extracting a tag from a packet received by the network device, the packet originating from a source executing on the source host machine and destined for the destination host machine, the tag being set by the source and indicating a first traffic class to be associated with the packet, the first traffic class being selected by the source from a plurality of traffic classes, the method comprising: determining, based on the tag, that the first traffic class corresponds to latency sensitive traffic; the network device processing the packets using one or more settings configured on the network device for processing packets associated with the first traffic class.

2. The method of claim 1 , wherein the network device is a top-of-rack switch or a spine switch.

3. 2. The method of claim 1, further comprising: setting a first set of parameters associated with the network device and / or a second set of parameters corresponding to a network interface card associated with the source host machine based on the first traffic class.

4. 4. The method of claim 3, wherein the first set of parameters associated with the network device includes a first parameter corresponding to a type of explicit congestion notification marking associated with the latency-sensitive traffic and a second parameter corresponding to a queue depth associated with the network device.

5. 2. The method of claim 1, wherein the tag is included in a type of service field included in a header portion of the packet, the type of service field being 8 bits in length, 6 bits of the type of service field being allocated to the tag, and 2 bits of the type of service field being allocated to a type of explicit congestion notification marking associated with the latency-sensitive traffic.

6. The method of claim 4 , wherein the type of explicit congestion notification marking associated with the latency-sensitive traffic corresponds to a deterministic and aggressive method of marking packets.

7. 7. The method of claim 6, wherein the deterministic and proactive method of marking packets is achieved by assigning a first value to a first threshold parameter associated with a number of packets contained in a queue of the network device, and assigning a second value to a second parameter corresponding to a probability of marking a packet.

8. The method of claim 7 , wherein the first value is set to 50 and the second value is set to 100%.

9. If the number of packets in the queue of the network device is greater than the first value, the second value is set to 100%; 9. The method of claim 8, wherein if the number of packets contained in the queue of the network device is less than the first value, the second value is set to 0%.

10. 4. The method of claim 3, wherein the second set of parameters corresponding to the network interface card associated with the source host machine includes an adaptive retransmit parameter, a slow restart parameter, a queue count parameter, and a packet sequence number parameter.

11. a processor; and a memory containing instructions that, when executed by the processor, cause the network device to perform at least: The instructions, when executed by the processor, cause the network device in a communication path between a source host machine and a destination host machine to extract a tag from a packet received by the network device, the packet originating from a source executing on the source host machine and destined for the destination host machine, the tag being set by the source and indicating a first traffic class associated with the packet, the first traffic class being selected by the source from a plurality of traffic classes, and the instructions, when executed by the processor, cause the network device to: determining, based on the tag, that the first traffic class corresponds to latency sensitive traffic; and processing the packets using one or more settings configured in the network device for processing packets associated with the first traffic class.

12. The network device of claim 11 , wherein the network device is a top-of-rack switch or a spine switch.

13. 13. The network device of claim 11 or claim 12, further configured to set a first set of parameters associated with the network device and / or a second set of parameters corresponding to a network interface card associated with the source host machine based on the first traffic class.

14. 14. The network device of claim 13, wherein the first set of parameters associated with the network device includes a first parameter corresponding to a type of explicit congestion notification marking associated with the latency-sensitive traffic and a second parameter corresponding to a queue depth associated with the network device.

15. 13. The network device of claim 11 or 12, wherein the tag is included in a type of service field included in a header portion of the packet, the type of service field being 8 bits in length, 6 bits of the type of service field being allocated to the tag, and 2 bits of the type of service field being allocated to a type of explicit congestion notification marking associated with the latency-sensitive traffic.

16. 15. The network device of claim 14, wherein the type of explicit congestion notification marking associated with the latency-sensitive traffic corresponds to a deterministic and aggressive method of marking packets.

17. 17. The network device of claim 16, wherein the deterministic and proactive method of marking packets is achieved by assigning a first value to a first threshold parameter associated with a number of packets contained in a queue of the network device and a second value to a second parameter corresponding to a probability of marking a packet.

18. 20. The network device of claim 17, wherein the first value is set to 50 and the second value is set to 100%.

19. If the number of packets in the queue of the network device is greater than the first value, the second value is set to 100%; 20. The network device of claim 18, wherein the second value is set to 0% if the number of packets contained in the queue of the network device is less than the first value.

20. A program comprising specific computer-executable instructions, which when executed by a processor, cause a computer system to perform the method of any one of claims 1 to 10.

Images