85 results about "Tier 2 network" patented technology

A Layer 2 network switch is partitionable into a plurality of switch fabrics. The single-chassis switch is partitionable into a plurality of logical switches, each associated with one of the virtual fabrics. The logical switches behave as complete and self-contained switches. A logical switch fabric can span multiple single-chassis switch chassis. Logical switches are connected by inter-switch links that can be either dedicated single-chassis links or logical links. An extended inter-switch link can be used to transport traffic for one or more logical inter-switch links. Physical ports of the chassis are assigned to logical switches and are managed by the logical switch. Legacy switches that are not partitionable into logical switches can serve as transit switches between two logical switches.

A virtual network is overlaid upon physical networks. The virtual network is a layer-2 network that appears to expand an organization's LAN using virtual MAC addresses. A VN device driver shim intercepts LAN packets and their virtual MAC and IP addresses and encapsulates them with physical packets that can be routed over the Internet. As new nodes are created, a VN switch table is expanded so that all nodes on the virtual network can reach the new node. A copy of the VN switch table is stored on each node by a virtual network management daemon on the node. A VN configuration controller in a central server updates the VN switch tables. Organizations can expand their virtual network as nodes are created at remote cloud computing providers without action by the staff at the cloud computing provider. Hybrid cloud virtual networks include on-premises physical and virtual-machine nodes, and off-premises guest nodes and instances.

Systems and methods are described for providing network route redundancy through Layer 2 devices, such as a loop free Layer 2 network having a plurality of switching devices. A virtual switch is coupled to the loop free Layer 2 network, the virtual switch having two or more switches configured to transition between master and backup modes to provide redundant support for the loop free Layer 2 network, the switches communicating their status through use of a plurality of redundancy control packets. The system also includes means for allowing the redundancy control packets to be flooded through the Layer 2 network. The means may include time-to-live data attached to the redundancy control packet which is decremented only when the packets are transferred through devices which are configured to recognize the protocol used in redundancy control packets.

A network connection device connecting a pseudo wire of a layer 2 and a pseudo wire formed of a layer 3, comprising: a switching unit operating as an edge switch of a layer 2 network forming a first pseudo wire; a routing unit operating as an edge router of a layer 3 network forming a second pseudo wire; and a conversion unit which makes conversion between a frame of the layer 2 network and a packet of the layer 3 network.

A LAN includes a router that is connected to two or more racks of servers and each of the servers can support a plurality of virtual machines. The router is configured to forward data packets based on IP destination addresses or based on destination MAC addresses and builds and maintains forwarding tables in support of data packet forwarding in the layer 3 and the layer 2 network environment. In support of layer 2 forwarding, the router builds and maintains an aggregated MAC switching table that is comprise of a subset of the table entries typically needed to switch packets to their destination, and in support of layer 3 forwarding, the router or switch builds and maintains an aggregated ARP forwarding table that is comprised of a subset of the table entries typically needed to forward packets to their destination.

The present invention discloses an efficient architecture for routing in a very large autonomous system where many of the layer 3 routers are attached to a common connection-oriented layer 2 subnetwork, such as an ATM network. In a preferred embodiment of the invention, a permanent topology of routers coupled to the subnetwork is connected by permanent virtual circuits. The routers can further take advantage of both intra-area and inter-area shortcuts through the layer 2 network to improve network performance. The routers pre-calculate shortcuts using information from link state packets broadcast by other routers and store the shortcuts to a given destination in a forwarding table, along with corresponding entries for a next hop along the permanent topology. The present invention allows the network to continue to operate correctly if layer 2 resource limitations preclude the setup of additional shortcuts.

A computer system automatically recovers from a split segment condition in which a contiguous layer 2 network segment, comprising a plurality of contiguous paths each directly coupling one or more members of a team of network resources of the computer system to a core switch of a layer 2 network, is split into two or more noncontiguous segments each comprising a contiguous set of one or more of the plurality of paths. The computer system includes a team of network resources having one or more members that couple it to each one of the plurality of paths. A teaming driver binds the drivers of each member of the team and is coupled to the segment through the members of the team. The teaming driver detects whenever the network segment has been split into two or more noncontiguous segments and then configures the team such that one of the members coupled to a path within each of the noncontiguous segments is designated as a primary resource thereby restoring connectivity of the isolated paths to the computer system.

A network having an access service network (“ASN”) configured to provide full mobility to mobile stations located within a service area. The ASN includes a Layer 2 or data link layer network that is larger, incorporates more nodes, or carries more data communications than Layer 2 networks incorporated in prior art ASNs. Data communications to and from the mobile stations are routed inside the ASN across the Layer 2 network which transports the data communication using a Layer 2 protocol. If the network includes another ASN located adjacent to the first ASN, the two ASNs may communicate directly with one another over a Layer 2 connection. If the network includes another ASN that is not adjacent to the first, Mobile Internet Protocol components may be included in the ASNs and configured to provide mobility between ASNs.

Techniques for facilitating link redundancy using an enhanced version of Virtual Switch Redundancy Protocol (VSRP), referred to herein as VSRP2. In one set of embodiments, a group of Layer 2 and/or Layer 2/3 devices (switches) can act in concert as a VSRP2 virtual switch. A first switch in the group (a VSRP2 master switch) can forward, via a first link, data traffic to/from a network device in a connected Layer 2 network. A second switch in the group (a VSRP2 backup switch) can block, at a second link, data traffic to/from the same network device. If the first link fails or otherwise becomes unavailable, the VSRP2 backup switch can detect the link failure and begin forwarding, via the second link, data traffic to/from the network device. In this manner, redundancy can be provided at the link level between the VSRP2 virtual switch and the Layer 2 network.

One embodiment pertains to a switching device which is configured to provide multicast traffic management in a layer 2 network without layer 3 devices A specific embodiment relates to a method of implementing IGMP multicasting in a layer 2 network. IGMP packets are snooped by multiple switches in the layer 2 network. IGMP query messages are generated by each of the multiple switches. IGMP join report messages are forwarded by each of the multiple switches to all ports on which a querier is present. Other embodiments are also disclosed.

A packet forwarding apparatus with a function of registering packet forwarding control information for each user terminal into a user management table during PPPoE connection and authentication phases in which the apparatus carries out predetermined communication procedures with each user terminal. During DHCP and IP forwarding phases following the authentication phase, the packet forwarding apparatus controls packet forwarding based on the user management table. Packets are forwarded in the form of PPPoE frame until the authentication phase is completed and packets are forwarded in the form of Ethernet frame in the DHCP and IP forwarding phases.

Spanning Tree Protocol (STP) data is obtained via network switch (SNMP) queries to enhance identification of switch-to-switch links in Layer-2 mapping. In particular, by analyzing the STP data, ambiguity in determining switch uplink ports may be reduced. Specifically, the STP data can be used in conjunction with other topography data to provide Layer-2 connectivity for nodes on a network topology. Layer-2 address mapping tables are collected from a topology mapping, and STP data is collected, along with address translation tables (ARP) tables. Using this information, switches are identified using Layer-2 address tables. The STP data can be correlated by comparing data in switches, identifying switch ports directly connected to other switch ports, and eliminating direct switch-to-switch port connections from consideration for further Layer-2 node mappings.

A solution is provided wherein the interfaces between multiple chassis (e.g., edge switches) in a network of layer 2 devices and a spanning tree device are treated as a single emulated switch. This emulated switch effectively enables two different views to the two different sides. Thus, frames from the network of layer 2 switches destined to any port of the emulated switch may take any of the links (through any of the physical switches), thereby enabling effective load-balancing for frames traveling from the layer 2 network side into the spanning tree device. Meanwhile the spanning tree device does not recognize an illegal loop in its connection to two different edge switches as it views the two links as a single logical EtherChannel.

A Layer 2 network switch is partitionable into a plurality of switch fabrics. The single-chassis switch is partitionable into a plurality of logical switches, each associated with one of the virtual fabrics. The logical switches behave as complete and self-contained switches. A logical switch fabric can span multiple single-chassis switch chassis. Logical switches are connected by inter-switch links that can be either dedicated single-chassis links or logical links. An extended inter-switch link can be used to transport traffic for one or more logical inter-switch links. Physical ports of the chassis are assigned to logical switches and are managed by the logical switch. Legacy switches that are not partitionable into logical switches can serve as transit switches between two logical switches.

Methods and systems for performing rate limiting are provided. According to one embodiment, multiple paths are provided between each pair of multi-path load balancing (MPLB) components within a Layer 2 network by establishing overlapping loop-free topologies in which each MPLB component is reachable by any other via each overlapping topology. A first MPLB component receives packets associated with a flow sent by a source component at a particular rate. The first MPLB component forwards the packets to a second MPLB component along a particular path in a network. A congestion metric for the particular path is determined. Based upon the congestion metric for the particular path, it is determined whether the particular path has reached a congestion threshold. In response to an affirmative determination, the source component is instructed to limit the rate at which it sends packets associated with the flow.

A data transmission system and method for transmitting packetized data from an Internet Protocol (IP) host, having at least an IP layer and a network layer, to a plurality of workstations by the intermediary of an IP network, wherein the IP host is connected to the IP network via a layer 2 network interfacing the IP network with a set of routers. The IP host further includes a Multiple Address Resolution Protocol (MARP) layer between the IP layer and the network layer for selecting one of the set of routers in response to the next hop IP addresses provided by the IP layer to the MARP layer when a packet of data is be transmitted from the IP host to one of the workstations.

Techniques for routing data between network area are disclosed, In one particular exemplary embodiment, the techniques may be realized as a method for routing data between layer 2 network areas of backbone bridges comprising the steps of receiving data at a network element containing an internally terminated Network to Network Interface (NNI) for a plurality of network areas, identifying a destination address associated with the data, determining a network area of the plurality of network areas associated with the data, and performing one or more data flow treatments associated with the data using the internally terminated Network to Network Interface (NNI).