Cascade optical switch

Abstract

An example cascade optical switch includes both a fast optical switch and a slow optical switch having an input port and an output port. The switching time of the slow-speed switch is longer than the switching time of the fast-speed optical switch. The cascaded optical switch includes a first pre-routed fiber connecting the output port of the slow optical switch to the input port of the fast optical switch, and a second pre-routed fiber connecting the output port of the fast optical switch to the input port of the slow optical switch. The fast optical switch or the slow optical switch is configured to receive configuration data to modify a switching configuration to configure a fiber cross-connect in an optical switching fabric comprising at least one of a first pre-wired fiber or a second pre-wired fiber.

Description

[0001] This application claims the benefit of U.S. Patent Application No. 17 / 819,797, filed on August 15, 2022, the entire contents of which are incorporated herein by reference. Technical Field

[0002] The present invention relates to computer networks and, more particularly, to interconnected computer networks. Background Art

[0003] A network service exchange provider or co-location provider ("provider") can employ communication facilities, such as a data center or warehouse, where multiple customers of the provider locate networks, servers, and storage devices with minimal cost and complexity and interconnect them to (multiple) providers of various telecommunications and other network services. A data center can be shared by multiple tenants of networking equipment located within a data center. With information technology (IT) and communication facilities in secure, secure delivery, telecommunications, the Internet, application service providers, cloud service providers, content providers, and other providers and enterprises enjoy less latency and the freedom to focus on their core business. Additionally, customers can reduce their business backhaul costs and free up their internal networks for other uses.

[0004] In some cases, a communications facility provides interconnection services by which the provider's customers can interconnect with each other over the communications facility infrastructure, or by which the provider's customers can interconnect their spatially and / or geographically distributed customer networking devices over the communications facility infrastructure. In such cases, the communications facility may be referred to as an "interconnection facility" or a "co-located facility."

[0005] One example of interconnection between different networks within an interconnection facility is a physical cross-connect, where the provider manually installs physical cables (such as CAT5 / 6, coaxial cables, or fiber optic cables) that then provide physical (e.g., "layer 0") connections between customer networks for either inter-customer interconnection (between different customers) or intra-customer interconnection (between areas of (multiple) interconnection centers operated / leased by a single customer). As described above, the fiber optic cable infrastructure is typically manually installed by the provider between customer spaces, with end-to-end or "main run" / "direct attach" fiber optic cables between the endpoints of the fiber optic cross-connects. In some cases, the provider uses structured cabling in the form of intermediate manual fiber optic patch panels in distribution facilities controlled by the provider, which allows the cross-connects to utilize shared / clustered fiber optic cabling between distribution facilities. In many cases, the optical fiber between distribution facilities is also manually installed per cross-connect.

[0006] Due in part to the phenomenal growth of Internet traffic and services, the fiber optic infrastructure in many communications facilities has become severely overloaded to the point where the maximum infrastructure capacity available to physically carry the optical fibers, such as overhead fiber trays, has been exceeded. Overloaded communications facilities have hindered the additional fiber cross-connects required to keep pace with the ever-increasing fiber optic port density of customer premises equipment, which is required to support the ever-increasing bandwidth and the new generation of fiber-rich networking equipment with high-density customer premises interfaces.

[0007] Furthermore, installing new fiber cross-connects across floors of an interconnect facility, between floors, across campuses, and across distributed interconnect facilities within a metropolitan area (or "metropolitan area") typically requires several man-days of work to determine infrastructure availability and to determine available physical paths through the various distributed facilities within the interconnect facility. As described above, fiber cross-connects typically require running home runs of fiber between fiber cross-connect endpoints located at respective demarcation points at customer spaces. Depending on the service, multiple patch panel connections may be required in addition to one or more fiber lines that create several segments from a customer space in a data center to another customer space in, for example, a different data center geographically located elsewhere in a metropolitan area.

[0008] Each fiber connection is typically manually designed for a specific cabling arrangement and typically has field terminations of the fiber end points. However, this may trigger operational issues when a customer disconnects the cross-connect after a period of operation. For example, when a customer requests a disconnection of the fiber cross-connect service, a provider technician digs out the fiber cables between the cross-connect end points by physically removing the fiber cables from the overhead fiber trays. When digging out the fiber cables for disconnection, other cables carrying live traffic for other customers may be inadvertently damaged, potentially violating service level agreements (SLAs) with other customers and potentially resulting in SLA penalties for the provider. Summary of the invention

[0009] Generally disclosed are technologies for cascaded optical switches that can be used to support fiber cross-connect automation solutions. The cascaded optical switches include fast switching, low port density switches ("fast switches") that are pre-wired and / or packaged within slow switching, high port density switches ("slow switches"). For example, the output ports of the slow switches can be pre-wired to the input ports of the fast switches, and the output ports of the fast switches can be pre-wired to the input ports of the slow switches. As a combination of fast switches and slow switches, the cascaded optical switches can actually provide a multi-stage Clos optical switching structure, in which the fast switches act as intermediate stages.

[0010] Cascade optical switches can be deployed as part of an optical switching fabric to support fiber cross-connects between networks co-located within a data center (or in multiple, geographically distributed data centers connected via optical fiber). The optical switching fabric can be pre-wired to connect the ports of the cascade optical switches to customer networks directly or via a patch panel.

[0011] The present technology may provide one or more technical advantages that enable at least one practical application. For example, unlike static fiber cross-connects, and also unlike dynamic fiber cross-connects that use optical switches to dynamically modify fiber connections between customer networks, cascaded optical switches support a more dynamic and optimized optical switching fabric that can address multiple different goals of providers and data center tenants / customers to meet different customer requirements regarding SLAs in large to hyperscale data centers presenting hundreds or thousands of connection opportunities.

[0012] For example, because the cascaded optical switches include both configurable fast optical switches and configurable slow optical switches, a fiber cross-connect provider (hereinafter referred to as an "interconnect provider") can provide various SLAs to meet various purposes / use cases. The slow optical switch has a high port count and can provide connections to more other networks than a single fast optical switch, but a single slow optical switch may not be able to address use cases that require shorter switching times, such as for failover / redundancy or faster interconnection. In addition, the interconnect provider can provide multiple SLAs and can provide the ability to change between service levels, such as changing the SLA. For example, the interconnect provider can provide a first service level that meets the first SLA, which can guarantee that the customer's interconnection order will be completed within 24 hours or less, for which the provider can reconfigure the slow switching structure. The interconnect provider can provide a second service level that meets the second SLA, which can guarantee that the customer's interconnection order will be completed within 30 minutes or less, for which the interconnect provider can use a fast switch. The interconnect provider can also provide services that allow customers to change their service levels. In response to changes in service requests, interconnect providers can utilize multiple switching technologies, such as by integrating one or more fast optical switches within a slow optical switch. As a result, cascaded optical switches will enable optical switch architectures to be highly optimized, flexible, and adaptable to customer needs.

[0013] In some examples, an optical switch fabric including cascaded optical switches can provide a mechanism for creating a multi-level architecture consisting of slow optical switches with large port counts and fast optical switches with relatively small port counts to provide automation for configuring fiber cross-connections in the optical switch fabric. An optical switch fabric including cascaded optical switches can provide a mechanism that packages one or more fast optical switches with relatively small port counts with slow optical switches with large port counts to prevent stranded capacity in one or more fast optical switches. An optical switch fabric including cascaded optical switches can provide a mechanism that: scales the size of fast optical switches by adding more fast optical switches as needed; disperses and distributes fast optical switches for defocusing by finding fast optical switches with the highest switching density; scales the size of fast optical switches independent of their technology (e.g., mechanical, mechanical, optical); and increases the availability of services by allowing fiber cross-connect services to be moved to or configured to include different types of switches (e.g., slow or fast) when there is a port or switch failure. In some examples, an optical switch fabric including cascaded optical switches can provide a mechanism that: permanently reserves and / or pre-provisions and / or pre-allocates specific customer ports directly to a fast optical switch via a slow optical switch prior to customer ordering (e.g., to ensure an SLA of less than 30 minutes); optimizes end-to-end (e.g., "A" to "Z") insertion loss in the cascaded / hybrid slow optical switch and fast optical switch fabric for an SLA of less than 30 minutes (e.g., relative to the cascaded all-fast optical switch fabric); automates optimization of fast optical switch port utilization (e.g., by allowing unused existing customer ports to be automatically released from pre-allocated fast optical switch ports to be reallocated to newly added customer ports based on customer demand); and enables oversubscription of fast optical switch ports (e.g., enabling a fast optical switch to be connected to more customer ports than it can handle and automatically provision ports to avoid port conflicts). Additionally, an optical switching fabric including cascaded optical switches can provide a mechanism for: creating universal customer ports to be used in the optical switching fabric, which universal customer ports can be dynamically allocated and used for multiple service levels (e.g., SLAs of less than 30 minutes or SLAs of less than 24 hours); creating dynamic protection and / or restoration of fiber cross-connections via backup and / or redundant fast optical switches (e.g., from a first fast optical switch to a backup and / or redundant fast optical switch); creating dynamic protection and / or restoration of fiber cross-connections via slow optical switches (e.g., from a first fast optical switch to a slow optical switch); and enabling deployment of an optical switching fabric including cascaded optical switches and the benefits of the optical switching fabric to multiple data centers.

[0014] In one example, the present disclosure describes a cascaded optical switch for an optical switching structure of a data center, the cascaded optical switch comprising: a fast optical switch having an input port and an output port; a slow optical switch having an input port and an output port, wherein a switching time of the slow optical switch is longer than a switching time of the fast optical switch; a first pre-wiring optical fiber, the first pre-wiring optical fiber connecting a first port, which is one of the output ports of the slow optical switch, to a second port, which is one of the input ports of the input ports of the fast optical switch; and a second pre-wiring optical fiber, the second pre-wiring optical fiber connecting a third port, which is one of the output ports of the fast optical switch, to a fourth port, which is one of the input ports of the input ports of the slow optical switch, wherein the fast optical switch or the slow optical switch is configured to receive configuration data to modify a switching configuration to configure a fiber cross-connection in the optical switching structure, the fiber cross-connection comprising at least one of the first pre-wiring optical fiber or the second pre-wiring optical fiber.

[0015] In another example, the present disclosure describes a method, the method comprising: receiving configuration data by a slow optical switch of a cascaded optical switch or by a fast optical switch of the cascaded optical switch to modify a switching configuration to configure a fiber cross-connection in an optical switch structure, the fiber cross-connection comprising at least one of a first pre-wired optical fiber or a second pre-wired optical fiber, wherein the fast optical switch comprises an input port and an output port, wherein the slow optical switch comprises an input port and an output port, wherein a switching time of the slow optical switch is longer than a switching time of the fast optical switch, wherein the first pre-wired optical fiber connects a first port as one of the output ports of the slow optical switch to a second port as one of the input ports of the fast optical switch, wherein the second pre-wired optical fiber connects a third port as one of the output ports of the fast optical switch to a fourth port as one of the input ports of the slow optical switch.

[0016] In another example, the present disclosure describes a system comprising: a programmable network platform configured to determine configuration data to modify a switching configuration to configure a fiber cross-connection in an optical switching structure; and a cascaded optical switch for an optical switching structure of a data center, the cascaded optical switch comprising: a fast optical switch having an input port and an output port; a slow optical switch having an input port and an output port, wherein a switching time of the slow switch is longer than a switching time of the fast optical switch; a first pre-wiring optical fiber connecting a first port, which is one of the output ports of the slow optical switch, to a second port, which is one of the input ports of the input ports of the fast optical switch; and a second pre-wiring optical fiber connecting a third port, which is one of the output ports of the fast optical switch, to a fourth port, which is one of the input ports of the input ports of the slow optical switch, wherein the fast optical switch or the slow optical switch is configured to receive configuration data from the programmable network platform to modify the switching configuration to configure a fiber cross-connection in the optical switching structure, the fiber cross-connection comprising at least one of the first pre-wiring optical fiber or the second pre-wiring optical fiber.

[0017] The details of one or more embodiments of the invention are set forth in the following drawings and description. Other features, objects, and advantages of the invention will be apparent from the description and drawings, and from the claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 is a block diagram illustrating an example interconnect system including cascaded optical switches, in accordance with one or more techniques of this disclosure.

[0019] Figure 2 is a diagram illustrating the process according to the technology described in this article Figure 1 00146] Block diagram of a high-level view of an example optical interconnect scheme for an example interconnect system of FIG.

[0020] Figure 3 is a diagram illustrating the process according to the technology described in this article Figure 1 FIG. 5 is a block diagram of a high-level view of another example optical interconnect scheme of an example interconnect system.

[0021] Figure 4 is a diagram illustrating the process according to the technology described in this article Figure 1 FIG. 5 is a block diagram of a high-level view of another example optical interconnect scheme of an example interconnect system.

[0022] Figure 5 is a block diagram illustrating an example architecture for a programmable network platform configured to dynamically provision optical fiber cross-connects within one or more interconnection facilities to interconnect multiple customers of an interconnection system provider.

[0023] Figure 6 is a block diagram illustrating further details of one example of a computing device operating in accordance with one or more techniques of this disclosure.

[0024] Figure 7 is a flow chart illustrating an example mode of operation for providing a fiber cross-connect with an interconnect system including cascaded optical switches according to one or more aspects of the present disclosure.

[0025] Figure 8 is a flow chart illustrating another example mode of operation for providing a fiber cross-connect with an interconnect system including cascaded optical switches according to one or more aspects of the present disclosure.

[0026] Like reference numerals refer to like elements throughout the drawings and text. DETAILED DESCRIPTION

[0027] Fiber cross-connects may be automatically provisioned between customers of an interconnection facility. In some examples, a programmable network platform for an interconnection facility exposes an interface through which customers of an interconnection system provider may request fiber cross-connects from other customers of the interconnection system provider, or through which the interconnection system provider may create such fiber cross-connects between customers. In response to a request for a fiber cross-connect, the programmable network platform may configure optical switches of the interconnection facility network infrastructure to create fiber cross-connects between demarcation points for interconnecting customers. The fiber cross-connects may facilitate non-blocking switching by high-speed fiber connections between respective customer spaces for customers, and in doing so may provide reliable and low-latency communications between respective demarcation points of the customer spaces. The fiber cross-connects may serve in this manner as the basis for higher-level network services exchanged between customers. Such network services may include Ethernet or other layer 2 (L2) services, Internet or other layer 3 (L3) services for direct L3 peering between customers, optical transport services for layer 0 and layer 1 (L0 / L1) services, and / or cloud-based service exchange whereby the interconnection facility operates as an L3 autonomous system for indirect L3 routing exchange between customers peering with the L3 autonomous system. In some examples, the programmable network platform may configure the optical switches of the interconnection facility network infrastructure to provide and / or provision one or more optical fiber cross-connects for dark fiber management.

[0028] In some examples, "customer" or "tenant" spaces located within an interconnection facility are each associated with a customer of an interconnection system provider. The interconnection system provider pre-installs a fiber optic infrastructure for an optical switch for the interconnection facility including one or more optical fibers to each customer space, such that a demarcation point for the customer space between the provider and the customer has a physical coupling with the pre-installed fiber optic infrastructure for sending and receiving optical signals through at least one optical fiber extending to the customer space demarcation point. In response to receiving a service request to create an optical fiber cross-connection between customer spaces for a corresponding customer, the programmable network platform configures the optical fiber switch of the interconnection facility to create an optical fiber cross-connection according to one or more optical paths determined by the programmable network platform for the requested optical fiber cross-connection and to exchange optical signals through the optical switch between the demarcation points.

[0029] As a result, the present technology can provide an automated fiber cross-connect service for quickly and automatically establishing physical fiber-level connections between many different types of services (e.g., cloud exchanges, Internet exchanges, Internet transit, optical transport) across floors of an interconnection facility, between floors, across campuses, and across distributed interconnection facilities within a metropolitan area using different network equipment (e.g., routers, switches, and optical dense wavelength division multiplexing (DWDM) transmission platforms). Such automated fiber cross-connects can be set up remotely and on-demand, with automated provisioning after manual pre-installation of the fiber infrastructure. The present technology can also allow optical performance monitoring and loopback for troubleshooting, as well as reduced capital expenditure (CapEx) investments due to better utilization of fiber tray space. As a result of the technology, short-term, temporary, and / or repeated fiber cross-connects can also be facilitated. One or more of the above advantages can facilitate service growth for interconnection service providers. Furthermore, because the fiber cross-connects are automatically provisioned, rather than using manually run fiber optic cables, the fiber cross-connects can also be automatically disconnected, and the fiber segments that make up the fiber cross-connects can be reused for new customers and / or new fiber cross-connects, which can alleviate the need to remove fiber optic cables from cable trays, and as a result, can improve overall SLA satisfaction due to fewer fiber optic cable breaks. Furthermore, for example, by provisioning fiber cross-connects within a centrally managed interconnection facility that is not publicly accessible, the present technology can provide more secure, more private, and lower latency connections than fiber-based connections established over a service provider's transport network.

[0030] Figure 1is a block diagram illustrating a high-level view of an interconnection system 2 having a programmable network platform 3 that provides automated fiber cross-connections between customer spaces of an interconnection facility in accordance with the techniques described herein. The interconnection system 2 depicts an interconnection facility 8 operated by an interconnection system provider, the interconnection facility 8 having an optical switch fabric including cascaded optical switches 10 that are configurable for cross-connecting customer networks located within a plurality of customer spaces 4A to 4F (collectively referred to as "customer spaces 4"). In some instances, each of the customer spaces 4 may be associated with a different customer of the interconnection system provider. In some instances, the customer spaces 4 are all associated with a single customer of the interconnection system provider. As used herein, the term "customer" of the interconnection system provider may refer to a tenant of the interconnection facility 8 deployed by the interconnection system provider, whereby a customer leases space within the interconnection facility 8 to co-locate with other tenants for increased efficiency over an independent facility, and to interconnect network equipment with network equipment of other tenants within the interconnection facility or campus for reduced latency / jitter and improved reliability, performance, and security compared to a transport network, among other reasons. In some cases, an interconnection system provider may be referred to as an interconnection facility provider as they are often the same entity.

[0031] In the interconnection facility 8, space may be divided and loaned to customers in groups in flexible increments in the form of spaces, such as cabinets, racks, suites (enclosed rooms that are not part of the common floor space), or other customer spaces in which customers may place their network equipment to provide network services to and / or receive network services from other customer(s) co-located in the interconnection facility 8. In some examples, a customer space may be an area and / or "cage" of common floor space surrounded by a fence or other demarcation. Although primarily illustrated and described with respect to customer spaces 4 in the interconnection facility 8, the techniques of the present disclosure are similarly applicable to automatically cross-connecting customer equipment distributed within the interconnection facility 8 (or distributed interconnection facilities) in a variety of spatial factors, such as those identified above.

[0032] Each of the spaces 4 is installed by the interconnection system 2 provider and provides a secure structure and location for customers to store and access their customer spaces while also having access to the optical network infrastructure and cascaded optical switches 10, for example, via the customer side of a fiber optic patch panel (not shown) located within the space 4, which defines a boundary or "demarcation" within the interconnection facility so that customers individually have access to the interior of the space. Such fiber optic patch panels (hereinafter referred to as "panels") can also provide the interconnection system 2 provider with convenient and secure access to the provider side of the panel. For example, a provider may be able to access the provider side of a panel for a space 4 without accessing the interior of the space 4. Similarly, a customer who rents or otherwise has access to the interior of a space 4 may be able to access the customer side of the panel but may be blocked from accessing the provider side of the panel. In some examples, a provider may be able to access a secure corridor between spaces 4, which may allow access to the provider side of the panel.

[0033] According to the techniques described in the present disclosure, the cascaded optical switch 10 may represent or may be included in an optical switch mechanism that includes an optical and photonic switching infrastructure that is configured by a programmable network platform 3 to automatically create a fiber cross-connection connecting a customer space 4. As described in further detail below, the cascaded optical switch 10 includes one or more fast optical switches (e.g., a fast optical switch 12 and a fast optical switch 14) and a slow optical switch 16. The slow optical switch has a longer switching time than the switching time of the fast optical switch 12 and the fast optical switch 14, for example, because the slow optical switch 16 can be switched sequentially and the optical fiber and / or connector may need to move a longer distance to establish a connection. In some examples, the slow optical switch 16 may be less expensive, more reliable, and / or more robust than the fast optical switch 12, the fast optical switch 14. For example, the slow optical switch 16 may not require continuous power or active maintenance to maintain a connection (e.g., latching). The slow optical switch 16 can have low optical insertion loss, e.g., lower insertion loss than the fast optical switch 12, 14, and can have field-replaceable electromechanical components. In some examples, the fast optical switch 12, 14 can have a higher per-port cost than the slow optical switch 16, can be non-locking (e.g., lose connection upon loss of power), and have a lower switching and / or port density, but the fast switch 12, 14 can have a faster switching time than the slow optical switch 16. In some examples, the fast optical switch 12 and / or the fast optical switch 14 can be configured to perform multiple switching actions, e.g., input / output port connections and / or reconnections, simultaneously and / or substantially simultaneously (e.g., as opposed to sequentially or "one at a time").

[0034] The cascaded optical switch 10 may include pre-wired (e.g., pre-installed or pre-provisioned) optical fibers 42A to 42F (collectively referred to as “pre-wiring 42”) connecting the output ports 22A to 22F of the slow optical switch 16 (collectively referred to as “slow switch input ports 22”) to the input ports 32A to 32F of the fast optical switch 12 and / or the fast optical switch 14 (collectively referred to as “fast switch input ports 32”). The cascaded optical switch 10 may also include pre-wired optical fibers 44A to 44F (collectively referred to as “pre-wiring 44”) connecting the output ports 34A to 34F of the fast optical switch 12 and / or the fast optical switch 14 (collectively referred to as “slow switch input ports 34”) to the input ports 24A to 24F of the slow optical switch 16 (collectively referred to as “fast switch input ports 24”).

[0035] Network traffic, data, signals, etc. that leave the slow optical switch via port 22 enter the fast optical switch 12 or the fast optical switch 14 via port 32, and network traffic, data, signals, etc. that leave the fast optical switch 12 or the fast optical switch 14 via port 34 enter the slow optical switch via port 24.

[0036] For the purpose of illustration and description, Figure 1 Describes the use Figure 1 directional optical communication from "left to right" in the input port 20, input port 32 and input port 24 and output port 22, output port 34 and output port 26. In some examples, each of the input ports 20, input port 32 and input port 24 will have a corresponding output port, and each of the output ports 22, output port 34 and output port 26 will have a corresponding input port to facilitate bidirectional optical cross-connection between the four pairs of customer spaces. In such an example, optical communication in the "right to left" direction will be pre-provisioned, and the fast switch 12, the fast switch 14 and the slow switch 16 will be configured with respect to Figure 1 Thus, while customer spaces 4A to 4C are primarily described as transmitting optical signals to customer spaces 4D to 4F, in some examples, additional ports and pre-wiring of slow switches 16 and fast switches 12, 14 will facilitate transmission of optical signals from customer spaces 4D to 4F to customer spaces 4A to 4C.

[0037] In the example shown, the cascade optical switch 10 may include (optionally redundant) pre-wired optical fibers connecting the input port 20 of the slow optical switch 16 to the customer space 4A to the customer space 4C and may also include (optionally redundant) pre-wired optical fibers connecting the output port 26 of the slow optical switch 16 to the customer space 4D to the customer space 4F. In some examples, multiple portions of the optical fiber cross-connections between the customer spaces 4 via the cascade optical switch 10 may include shared / clustered optical fiber wiring, and the interconnection facility 8 may include one or more optical fiber patch panels, such as the optical fiber patch panel 6 and the optical fiber patch panel 9 in the example shown, to utilize the shared / clustered optical fiber wiring (each of the optical fiber patch panel 6 and the optical fiber patch panel 9 may represent a plurality of optical fiber patch panels). The cascade optical switch 10 may include one or more optical fiber patch panels, such as the optical fiber patch panel 7 and the optical fiber patch panel 8 in the example shown, to facilitate easier reconfiguration of the connection between the output port 22 and the input port 32 and the connection between the output port 34 and the input port 24.

[0038] Fast switches 12, fast switches 14, and slow switches 16 may be located in an interconnect provider space within interconnect facility 8. Customers may be prevented from accessing the interconnect provider space to modify the wiring or configuration of fast switches 12, fast switches 14, and slow switches 16.

[0039] The cascaded optical switch 10 may provide one or more technical advantages that enable at least one practical application. For example, once a fiber cross-connect is formed (e.g., provisioned), the portion of the fiber cross-connect that includes the slow switch 16 does not require power to maintain the connection (latching). Unlike a single fast switch, the slow switch 16 can also be serviced without interrupting existing connections, and even during power or other scenarios, the slow switch 16 will maintain its connection to carry network / signal / data traffic. In some examples, in contrast to other switching schemes, the cascaded optical switch 10 does not significantly affect the total end-to-end fiber cross-connect link budget across the cascaded optical switches 10 (e.g., due to signal losses of physical connections or interconnections at ports, patch panels, etc.) because the slow optical switch 16 has lower insertion loss than the fast switch.

[0040] Additionally, the cascaded optical switches 10 can provide maintenance of service levels, e.g., less than 30 minutes SLA, when installing / uninstalling customer fiber cross-connects. For example, the slow switches 16 can be configured to provision connections between pre-wired infrastructure, e.g., pre-wired ports 22 and 32 at patch panel 7, pre-wired ports 34 and 24 at patch panel 8, and pre-wired customer space 4 ports at patch panel 6 to port 20 and at patch panel 9 to port 26. In other words, the slow switches 16 of the cascaded optical switches 10 can be configured to "re-fiber" the pre-wired infrastructure so that pre-assigned ports of the fast switches 12, 14 can be reallocated to existing or additional customer spaces 4. For example, using the cascaded optical switches 10, the interconnection system 2 can be configured to dynamically reallocate unused ports of the fast optical switches 12, 14 via the slow optical switches 16 to improve utilization of the ports of the fast switches 12, 14. If there is a new demand for an SLA of less than 30 minutes from an existing or new customer space 4, the unused ports can be re-routed or reallocated via the slow optical switch 16 for new pre-wiring allocations to the pre-existing or new customer space 4, for example, without impacting existing network / signal / data traffic on other customer ports. In this manner, among other things, the cascaded optical switches can provide improved port utilization and reduced CapEx expense to deploy additional fast optical switches. In some examples, the slow switch 16 can be configured to "re-fiber" the pre-wiring infrastructure sequentially, and if multiple reconfiguration actions are requested to occur substantially simultaneously or during the same time period, the slow switch 16 can exceed the 30 minute SLA. However, operating sequentially, the slow switch 16 can still be configured to "re-fiber" the pre-wiring infrastructure and still meet the less than 30 minute SLA by optimizing the multiple reconfiguration actions requested.

[0041] The slow optical switch 16 and the fast optical switch 12 and / or the fast optical switch 14 can be configured to receive configuration data to modify the switching configuration to reconfigure the optical fiber cross-connections in the optical switching structure, the optical fiber cross-connections including at least one of the pre-wired optical fibers connecting the output port 22 to the input port 32 or at least one of the pre-wired optical fibers connecting the output port 34 to the input port 24.

[0042] The system 2 also includes a programmable network platform (PNP) 3, alternatively referred to herein as an "interconnection platform". The programmable network platform 3 can expose a software interface defining methods, fields, and / or other software primitives, through which (multiple) applications 5 can call the PNP 3 to dynamically provision fiber cross-connects between customer spaces 4. In this way, the PNP 3 allows customers, carriers, network service providers (NSPs), and / or interconnection system providers themselves to have programmable capabilities to configure optical switch fabrics and cascade optical switches 10 to interconnect customer spaces 4.

[0043] The programmable network platform 3 may represent an application executing within one or more data centers of the system 2, or alternatively, an application executing off-site / remotely, for example, at a backend or branch of a provider of the interconnection system 2. The programmable network platform 3 may control service provisioning for a plurality of different interconnection facilities. Alternatively or additionally, a plurality of separate instances of the programmable network platform 3 may control service provisioning for a corresponding plurality of different interconnection facilities.

[0044] Application(s) 5 represent at least one application that communicates with the PNP 3 to request and dynamically provision fiber cross-connects within the optical switch fabric including the cascaded optical switches 10 and to establish fiber-based connections between customer spaces 4. Application(s) 5 represent client-side software for interfacing with the PNP 3 and may include a customer portal, customer applications, interconnection system 2 provider applications accessible only by operators of the interconnection facility 8, consoles such as command line interfaces or graphical user interfaces. Users and customers of the application(s) 5 may include, for example, enterprise customers, cloud service and content providers, carriers, network service providers (NSPs), and / or the interconnection system providers themselves.

[0045] An application of the application(s) 5 issues a fiber cross-connect request 11 to the PNP 3 specifying parameters for a fiber cross-connect between the customer spaces 4. For example, the fiber cross-connect request 11 may specify an optical signal profile including bandwidth or data rate and protocol, a start time when the requested fiber cross-connect should be operational, an end time when the requested fiber cross-connect should be removed (possibly indefinitely until expiration of a contract period), and a port identifier for a panel port at an interface panel of the customer space 4.

[0046] In response to the fiber cross-connect request 11, the PNP 3 determines the optical path through the optical switching fabric and the cascaded optical switches 10 and dynamically provisions the optical cross-connects in the optical switching fabric and the cascaded optical switches 10 to provide optical fiber-based interconnections between the customer spaces 4 to satisfy the fiber cross-connect request 11. The PNP 3 can determine the optical path through the cascaded optical switches 10 by identifying pre-installed but unused optical fibers connected to unused ports on the photonic switch connections that together constitute the end-to-end optical path between the customer spaces 4. In some examples, the grid of cascaded optical switches constitutes an optical switching fabric of an interconnect facility or multiple interconnect facilities. The optical switching fabric may include additional optical devices, including other optical fast switches or optical slow switches.

[0047] The PNP 3 configures the elements of the optical switching fabric and the cascaded optical switches 10 by issuing configuration commands to the elements directly through their configuration interfaces, or indirectly via a software defined network (SDN) controller that manages the elements on behalf of the PNP 3. In some instances, the PNP 3 may alternatively be referred to as a coordinator because the PNP 3 coordinates the SDN controller to configure the photonic switches and / or other elements of the optical switching fabric 10 to establish fiber cross-connects between the customer space 4 pairs.

[0048] The fiber cross-connects involving the cascaded optical switches 10 may represent layer 0 ("L0") connections, as fiber cross-connects are the basis of the Open Systems Interconnection (OSI) model or the TCP / IP model for packet networking. In particular, fiber cross-connects may serve as the basis of an optical transport network (OTN) that provides layer 1 ("L1") connections between optical networking equipment such as wavelength division multiplexing (WDM) equipment (typically in conjunction with the SONET / SDH layer). For example, a fiber cross-connect may represent one or more wavelengths (or "lambdas") that are photonically switched by elements of an optical switching fabric to provide optical paths (or "lightpaths") for optical signals exchanged between customer spaces 4 associated with different customers / tenants of the provider of the interconnection system 2. In this manner, the optical switching fabric including the cascaded optical switches 10 is configured to provide non-blocking switching to customers of the provider of the interconnection system 2 via high-speed fiber connections between the respective customer spaces 4, and in doing so may provide reliable and low-latency communications between respective demarcation points of the customer spaces 4.

[0049] The customer networks (not shown) use corresponding access links (not shown) to access the fiber cross-connects of the cascade optical switches 10 to exchange data. In some examples, the access links may represent gray links / optical devices, where a router or switch of the customer network exchanges gray (uncolored) optical signals with a transponder that converts between the gray optical signals and optical signals of a specific wavelength (color) exchanged with the optical switching fabric and the WDM equipment of the cascade optical switches 10. In some cases, the fiber cross-connects may serve as the basis for layer 2 ("L2") or layer 3 ("L3") services provided by the interconnection system 2 provider to interconnect customer spaces 4 according to L2 or L3 services. For example, the interconnection facility 8 may operate a network service exchange such as an Ethernet exchange, and an Internet exchange and / or a cloud exchange, and each of these network service exchanges may use dynamically provisioned fiber cross-connects 7 to transport L2 / L3 packet data between customer networks.

[0050] Further example details of facilities for providing cloud-based services exchanges are found in U.S. Provisional Patent Application No. 62 / 149,374, filed on April 17, 2015, and entitled “Cloud-Based Services Exchange”; U.S. Provisional Patent Application No. 62 / 072,976, filed on October 30, 2014, and entitled “INTERCONNECTION PLATFORM FOR REAL-TIME CONFIGURATION AND MANAGEMENT OF ACLOUD-BASED SERVICES EXCHANGE”; and U.S. Provisional Patent Application No. 62 / 160,547, filed on May 12, 2015, and entitled “PROGRAMMABLE NETWORK PLATFORM FOR A CLOUD-BASED SERVICES EXCHANGE,” each of which is incorporated herein by reference in its entirety.

[0051] As a result of dynamically provisioning cross-connects between customer spaces 4 via cascaded optical switches 10, the technology can allow an interconnect provider to offer various SLAs to customers to meet various purposes / use cases. Slow optical switches 16 have high port counts and can provide connections to more other networks than fast optical switches 12 and / or fast optical switches 14, but slow optical switches 16 alone may not be able to address use cases that require shorter switching times (such as for failover / redundancy or faster interconnect). In addition, the interconnect provider can offer multiple SLAs and can provide the ability to change between service levels, for example, to change the SLA. For example, the interconnect provider can offer a first service level that meets the first SLA, and the first SLA can guarantee that the customer's interconnection order will be completed in 24 hours or less (e.g., an SLA of less than 24 hours), for which the provider can reconfigure the slow switch 16. The interconnection provider may provide a second service level that meets a second SLA, which may guarantee that the customer's interconnection order will be completed in 30 minutes or less (e.g., a less than 30 minute SLA), for which the provider may use one or more fast switches, such as fast switch 12 and / or fast switch 14. The interconnection provider may also provide layers of SLAs and allow customers to change their service levels. In response to changes in service requests, the interconnection provider may utilize multiple switching technologies, such as by integrating one or more of the fast optical switches 12 and / or fast optical switches 14 within the slow optical switch 16. As a result, the cascaded optical switch 10 will enable the optical switch structure to be highly optimized, flexible, and adaptable to customer needs.

[0052] Figure 2 It is a diagram illustrating the process according to the technology described in this article Figure 1 1 is a block diagram of a high-level view of an example optical interconnection scheme of an example interconnection system 2. In the example shown, the interconnection system 2 is provided to provide a fiber cross-connect 50, a fiber cross-connect 52, a fiber cross-connect 54, a fiber cross-connect 56, and a fiber cross-connect 58. The fast optical switch 12, the fast optical switch 14, or the slow optical switch 16 can be configured to modify the switching configuration of the cascaded optical switch 10 to reconfigure the fiber cross-connects between the spaces 4 in the optical switch fabric, for example, the fiber cross-connect 50 to the fiber cross-connect 58, each including at least one of the pre-wired optical fibers 42 or the pre-wired optical fibers 44.

[0053] For example, a customer may request a fiber cross-connect with an SLA of less than 30 minutes between customer space 4A and customer space 4F. PNP 3 may determine configuration data to modify the switching configuration of cascade optical switch 10, and fast optical switch 12, fast optical switch 14, or slow optical switch 16 may receive the configuration data and modify the switching configuration via pre-wired optical fiber 42A and pre-wired optical fiber 42F to reconfigure fiber cross-connect 50.

[0054] In some examples, multiple ports of the fast switch 12 and the fast switch 14 may be pre-wired to ports of the slow switch 16. When there is a new demand from a customer, for example, for a fiber cross-connect with an SLA of less than 30 minutes, the PNP 3 may provision a switch connection across the fast switch 12 or the fast switch 14 to meet the new demand to utilize the existing pre-wiring 42, 44, rather than requiring new wiring to the open ports of the fast switch 12, the fast switch 14. Additionally, the cascaded optical switch 10 may be used for port twisting of the fast optical switch 12, the fast optical switch 14.

[0055] As another example, the new customer demand may be for fiber cross-connects 54, 58 between additional customer space 4G and customer space 4E and customer space 4F with an SLA of less than 30 minutes. PNP 3 may determine that the previous customer demand for fiber cross-connects 52, 56 is no longer required, and may send configuration data for the slow optical switch 16 to re-provision fiber cross-connects 52, 56 to fiber cross-connects 54, 58. For example, the slow optical switch 16 is configured to switch the port connections to port 32C and port 32F without rewiring, rather than input port 32C and input port 32F being stranded by the previous customer demand or having to rewire port 32C and port 32F. In the example shown, the slow optical switch 16 is configured to receive configuration data from the PNP 3 and to modify its switching configuration to re-supply ports 32C and 32F to connect to ports 20G and 20H, respectively, to reconfigure fiber cross-connects 52 and 56 to fiber cross-connects 54 and 58, respectively.

[0056] In some examples, the cascaded optical switches 10 are configured to allow oversubscription of the fast optical switches 12, 14. For example, the cascaded optical switches 10 may include a total number of ports prewired to the ports of the customer space 4 that is greater than the total number of ports of the fast switches 12, 14 alone or together, and the fast optical switch 16 is configured to dynamically reallocate unused fast switch 12, 14 ports, for example, as described above with respect to new (and / or changed) customer needs. In the illustrated example, the slow switch 16 includes ports 20A to 20H and ports 26A to 26F prewired to the customer space 4, and the fast switches 12, 14 together include ports 32A to 32F and ports 24A to 34F prewired to other ports (e.g., 12 ports) of the slow optical switch 16. In the example shown, the slow optical switch 16 is configured to dynamically switch between ports prewired to customer spaces and ports prewired to the fast switches 12 and 14, for example, switching between connecting port 22C (which is prewired to port 32C of the fast optical switch 12) to port 20B and port 20G (both of which are prewired to customer spaces, such as space 4B and space 4G, respectively).

[0057] Figure 3 It is a diagram illustrating the process according to the technology described in this article Figure 1 FIG. 2 is a block diagram of a high-level view of another example optical interconnection scheme of an example interconnection system 2. In the example shown, the interconnection system 2 includes a fiber cross-connect 60, a fiber cross-connect 62, a fiber cross-connect 64, and a fast optical switch P.

[0058] The fast optical switch P can be used as a backup fast optical switch, for example, a "protection" fast optical switch in the event of a failure of the fast optical switch 12 or the fast optical switch 14. The cascaded optical switch 10 in this example implementation includes one or more protection fast optical switches P, which can reduce switch fabric downtime and improve system availability, for example, in the event of a failure. In some examples, all ports of the protection fast optical switch P can be pre-wired to ports of the slow switch 16, for example, input port 32X, input port 32Y and output port 34X, output port 34Y can be pre-wired to ports of the slow switch 16, for example, via pre-wired optical fiber 42X, pre-wired optical fiber 42Y and pre-wired optical fiber 44X, pre-wired optical fiber 44Y.

[0059] In some examples, in the event of a fast switch port failure or an entire fast switch failure, the fast optical switch 12, the fast optical switch 14, the fast optical switch P, or the slow optical switch 16 can be configured to modify the switching configuration of the cascaded optical switch 10 to reconfigure the fiber cross-connections between the spaces 4 in the optical switch fabric, for example, the fiber cross-connect 60 to the fiber cross-connect 66, the fiber cross-connections including the pre-wired optical fibers 44 or at least one of the pre-wired optical fibers 44. The fast optical switch 14, the fast optical switch P, or the slow optical switch 16 can be configured to modify the switching configuration to switch from the failed port of the fast optical switch to another port of the same fast switch, to another port on a different fast optical switch, to switch all ports of the failed fast optical switch to a different fast optical switch (e.g., to protect the fast optical switch P), or to bypass the fast optical switch and supply the fiber cross-connections within the slow switch 16 (e.g., in the event of a catastrophic failure that no longer provides an SLA of less than 30 to one or more fiber cross-connections).

[0060] For example, the cascaded optical switch 10 can be configured to provision a fiber cross-connect 60 between customer space 4A and customer space 4D. Port 32A may experience a failure, and the slow switch 16 can be configured to then re-provision the fiber cross-connect, for example, to provision a fiber cross-connect 62 between customer space 4A and customer space 4D via another available port of the same fast optical switch (e.g., by switching input port 20A to output port 22B in the slow optical switch 16 instead of port 32B of the fast optical switch 12 to output port 22A).

[0061] Additionally or alternatively, the slow switch 16 can be configured to re-provision the fiber cross-connection between the customer space 4A and the customer space 4D via another available port of a different fast optical switch (e.g., port 32X of the fast optical switch P to provision the fiber cross-connection 64). For example, if only a few ports of the fast optical switch 12 are shut down, such as port 32A, the PNP 3 can automatically reassign the respective failed ports to good (e.g., functional) ports in the fast optical switch P and automatically copy the failed port connection data (e.g., stored in the connection database of the system 2) of the failed ports (e.g., port 32A) of the fast optical switch 12 to the fast optical switch P (e.g., so that the connection data of those ports can be restored or re-associated with the fast optical switch once the failed ports are restored). In some examples, each fast optical switch of the cascade optical switch 10 can have a dedicated fast optical switch P, and in other examples, for example, on a port-by-port basis, two or more of the fast optical switches of the cascade optical switch 10 can share one or more fast optical switches P.

[0062] In some examples, the fast optical switch P may be a backup or redundant switch for the fast optical switch 12 and / or the fast optical switch 14. For example, if the fast optical switch 12 fails, the PNP 3 may automatically reallocate all pre-wired connections to the customer space 4 from the fast optical switch 12 to the fast optical switch P via the slow optical switch 16 and replicate the connection data of all ports of the fast optical switch 12 to the fast optical switch P, i.e., configure the fast optical switch P to replicate the optical connection between the output port 22 and the input port 24 of the slow optical switch 16 that was previously provided by the fast optical switch 12.

[0063] In some examples, each fast optical switch of the cascaded optical switch 10 can have a dedicated, redundant instance of a fast optical switch P. In other examples, two or more fast optical switches of the cascaded optical switch 10 can share one or more fast optical switches P, for example, on a port-by-port basis or on a switch-by-switch basis.

[0064] Additionally or alternatively, the slow switch 16 can be configured to re-provision the fiber cross-connect between customer space 4A and customer space 4D without using a fast optical switch, for example, to provision the slow optical switch 16 via the fiber cross-connect 66 to connect port 20A and port 26B, for example, in the event of a failure of all fast switches and / or ports, as a failsafe to still maintain the fiber cross-connect, albeit at a different SLA level, for example, less than a 24 hour SLA.

[0065] In the illustrated example, the cascaded optical switch 10 together with software automation (e.g., via PNP 3) can provide improved network / signal / data traffic reliability, e.g., by improving the speed of restoration of network / signal / data traffic of a failed port, e.g., within minutes instead of hours, e.g., less than about five minutes. Additionally, the cascaded optical switch 10 can provide improved restoration time of network / signal / data traffic of an entire fast optical switch from a failure, e.g., within hours instead of days.

[0066] In some examples, the cascade optical switch 10 can be configured to dynamically reallocate ports for different SLA levels (e.g., between an SLA of less than 30 minutes and an SLA of less than 24 hours), for example, to effectively enable one or more ports to become "general purpose" ports. For example, a port at a customer space 4 can be a general and / or general purpose port rather than a port with a dedicated service level, such as via pre-wiring to port 20. In some examples, the system 2 is configured to allow a customer to dynamically allocate and change port allocations for a customer space 4 via the cascade optical switch (e.g., via interaction with an application 5).

[0067] For example, a customer of customer space 4A may request an SLA of less than 30 minutes for ports of customer space 4A, e.g., pre-wired to port 20A of slow optical switch 16, and then cascade optical switch 10 may configure slow optical switch 16 and fast optical switch 12 to provision fiber cross-connects 60 (e.g., via provisioning port connections between ports 20A, 22A, and ports 24B, 26B in slow optical switch 16 and ports 32A, 34B in fast optical switch 12). In some examples, slow optical switch 16 may be pre-provisioned, e.g., between ports 20A, 22A, and ports 24B, 26B during or prior to a customer request for an SLA of less than 30 minutes, and cascade optical switch 10 may only need to provision fast optical switch 12 to provision fiber cross-connects 60 upon customer request for an SLA of less than 30 minutes. The customer may then request a change in the service level for port 20A (equivalent to a port of customer space 4A prewired to port 20A), such as to an SLA of less than 24 hours, and the cascade optical switch 10 may dynamically reconfigure the slow optical switch 16 to provision the fiber cross-connect 66, such as by provisioning a port connection between port 20A and port 26B of the slow optical switch 16. The customer may then request another change in the service level for port 20A back to an SLA of less than 30 minutes, and the cascade optical switch 10 may then reconfigure the slow optical switch 16 and the fast optical switch 12 to provision the fiber cross-connect 60. In some examples, the PNP 3 and / or the cascade optical switch 10 may be configured to prioritize the requests. For example, the slow optical switch 16 may have a queue for requesting and / or updating the fiber cross-connect. Fiber cross-connect requests for SLAs less than 30 minutes may have a high priority, and the PNP 3 and / or the cascade optical switch 10 may send configuration data to the slow optical switch 16 that includes a priority level and / or a command to prioritize requests within a queue for the slow optical switch 16. For example, the PNP 3 may be configured to determine that input ports 20A to 20F are pre-provisioned and pre-connected to output ports 22A to 22F, and that input ports 24A to 24F are pre-provisioned and pre-connected to output ports 26A to 26F. The PNP 3 may then determine the priority assignments so that when switching between SLA levels, for example, from an SLA of less than 30 minutes to an SLA of less than 24 hours, and back to an SLA of less than 30 minutes, the ports may be used for and meet the different SLA levels.

[0068] Figure 4 It is a diagram illustrating the process according to the technology described in this article Figure 1FIG. 2 is a block diagram of a high-level view of another example optical interconnect scheme of an example interconnect system 2. In the example shown, the interconnect system 2 includes a fiber optic cross-connect 70 and a fiber optic cross-connect 72.

[0069] In the illustrated example, the cascaded optical switch 10 is dynamically reconfigured from switching the input port 20A to the output port 26A as a fiber cross-connect 70 between the customer space 4A and the customer space 4D to instead switching the input port 20A to the output port 26B as a fiber cross-connect 72 between the customer space 4A and the customer space 4E, for example, for a short duration, and then back to the fiber cross-connect 70. To accomplish this, the PNP 3 reconfigures the fast switch 12 of the cascaded optical switch 10 to switch the input port 32A from the output port 34A to the output port 34B, thereby achieving a fast switching reconfiguration of the fiber cross-connect for the customer space 4A from one destination customer space 4D to another destination customer space 4E without requiring rewiring, and achieving a faster reconfiguration than would be achieved using the slow optical switch 16 alone.

[0070] Figure 5 is a block diagram illustrating an example architecture for a programmable network platform 300 configured to dynamically provision optical fiber cross-connects within one or more interconnection facilities to interconnect multiple customers of an interconnection system provider. Figure 5 A programmable network platform 300 including multiple components is illustrated, which together provide dynamic configuration and management of metro-based interconnection facilities, particularly dynamic provisioning of optical fiber cross-connections. The programmable network platform 300 includes a centralized network control (CNC) system 302 and one or more network field units (NFUs) 304 configured to interface with one or more software defined networking (SDN) controllers 306, one or more hardware configurators 308, one or more infrastructure data collectors 310, and an information technology system 322. The programmable network platform 300 may represent an example instance of the programmable network platform 3 or another programmable network platform, controller, or system described herein for automatically provisioning optical fiber cross-connections using cascaded optical switches.

[0071] The programmable network platform 300 can provide coordination of optical fiber cross-connect services. Figure 5In the example of , CNC system 302 implements automation in the provisioning of fiber cross-connects. As such, CNC system 302 may provide one or more software interfaces that allow customers to establish, offload, and manage interconnections with other customers, such as one or more cloud service providers co-located in an interconnection facility, in an automated and seamless manner. CNC system 302 may include logic that receives business service requests via API calls and converts them into necessary business instantiation parameters and network provisioning parameters to be delivered and guaranteed as a business service. CNC system 302 may be the central intelligent processing unit of a coordination system (e.g., programmable network platform 300), and one logical instance of the intelligent logic may exist per instantiation.

[0072] In some examples, NFU 304 is implemented as an independent unit that receives requests or instructions from CNC system 302 to configure a network infrastructure of a specific interconnection facility for one or more services. For example, NFU 304 may include a combination of hardware and software. In some examples, NFU 304 may be a virtual machine. In any case, NFU 304 receives a request or instruction from CNC system 302 based on a customer request submitted to CNC system 302. As further described below, NFU 304 can determine whether there are sufficient resources to provide the service requested by CNC system 302. If there are sufficient resources, NFU304 can communicate with SDN controller 306, hardware configurator 308, and infrastructure data collector 310 or otherwise interoperate to configure the network infrastructure to provide the requested service. NFU 304 can represent a globally distributed intelligent logic unit that receives network instantiation commands from CNC system 302 and instantiates and configures the network resources required to deliver the service. The NFU 304 may have the intelligence to deliver and guarantee network services as requested by the CNC system 302 and also have the ability to communicate with third party coordination systems if the service request requires it.

[0073] In some examples, multiple interconnection facilities may be geographically dispersed. Each geographically located interconnection facility may have a corresponding NFU that is geographically located at the same location as the corresponding cloud exchange point. The corresponding NFU may configure and otherwise manage the network infrastructure and optical switching structure of a particular geographically located interconnection facility. In this manner, a particular NFU may receive a request or instruction from the CNC system 302 and configure the network infrastructure and optical switching structure of the interconnection facility managed by the particular NFU. In some cases, multiple interconnection facilities in a metropolitan area constitute a metropolitan-based interconnection facility managed by a single NFU.

[0074] NFU 304 may thus represent a distributed processing unit of programmable network platform 300 that provides horizontal scaling and the ability to deliver and guarantee services to programmable network platform 300. NFU 304 is a component of programmable network platform 300 that can provide functionality to deliver services in a vendor-agnostic and form factor-agnostic manner. Figure 5 As shown, the NFU 304 has several software components that enable the distributed processing units to deliver services.

[0075] In order to provision fiber optic cross-connects to customers and providers co-located in an interconnection facility managed by the PNP 300, the CNC system 302 includes a service selector 312. In some examples, the service selector 312 can operate as an API gateway. For example, the service selector 312 can expose a software interface defined according to one or more APIs. Requests and / or instructions received by the service selector 312 may include the form of create, read, update and / or delete (CRUD) requests made regarding fiber optic cross-connects provided and / or delivered by the interconnection facility. An application can call an endpoint of an API provided by the service selector 312, which in turn can call the fiber optic cross-connect provisioning engine 314. For example, the service selector 312 can be executed on one or more virtual machines and / or real servers. Although in Figure 5 312 is shown as a single element, but the service selector 312 may include a cluster of one or more physical and / or virtual computing machines executing on one or more physical processors. In some aspects, the service selector 312 provides a service catalog describing available services and providers for the available services.

[0076] The fiber cross-connect engine 314 may receive a request to provision a service from the service selector 312. The fiber cross-connect engine 314, in conjunction with the network field unit 304, organizes, directs, and integrates the underlying hardware and software subsystems for managing various aspects of service provisioning within the network infrastructure and cloud service management. For example, the fiber cross-connect provisioning engine 314 may provide a rule-driven workflow engine to at least one interconnection facility configured by the network field unit 304, which operates between the service selector 312 and the underlying optical switching fabric. In this manner, the fiber cross-connect provisioning engine 314 may be invoked by a customer-specific application or a customer portal based on the interconnection system provider via the service selector 312 for directly participating in the programmable network platform 300 of the automated fiber cross-connect infrastructure configured by the network field unit 304. As further described below, the NFU 304 may receive instructions and / or requests from the CNC system 302, which the NFU 304 uses to provision segments of end-to-end fiber cross-connects at the interconnection facility.

[0077] The fiber cross-connect provisioning engine 314 may query and store service telemetry and analytical data (STAD) 316 in one or more data repositories. The STAD 316 may include metrics about the number, type, definition, and customers of cross-connect services configured by the fiber cross-connect provisioning engine 314. The STAD 316 may include analytical information based on raw metric data from the NFU 304. For example, the analytical information of the STAD 316 may include historical statistics and / or real-time statistics, which may be analyzed in various dimensions, such as customers, service types, service usage, to name a few examples. In some examples, the PNP 3 may be used to configure multiple types of services in addition to cross-connects.

[0078] The CNC system 302 may also include financial logic 318. The financial logic 318 may store billing information for a customer. For example, the financial logic 318 may store billing information for a customer, such as name, address, phone number, email, to name a few examples. When the fiber cross-connect provisioning engine 314 configures a fiber cross-connect service for a customer that includes a service fee, the financial logic 318 may store such fee information. In this manner, the financial logic 318 may provide billing for services purchased by a customer and provide a bill for such services.

[0079] The CNC system 302 may include an IT gateway 320 that interfaces with an information technology (IT) system 322. The IT system 322 may include one or more computing devices, such as desktop computers, tablet computers, smart phones, and servers, to name a few examples. The IT system 322 may provide one or more user interfaces to an administrator, who may use the IT system 322 to manage the CNC system 302. For example, the IT system 322 may receive user input to configure the CNC system 302 and / or the NFU 304. Based on the user input, the IT system 322 may send requests and / or instructions to the CNC system 302 that may be received by the IT gateway 320. In some examples, the CNC system 302 may provide or otherwise expose one or more RESTful interfaces that are called or otherwise invoked by the IT system 322. The IT gateway 320 may route such instructions or requests to other components within the CNC system 302 for further processing based on the type of request and / or instruction.

[0080] As described above, the NFU 304 may receive a request or instruction to provision one or more cross-connect services from the CNC system 302. The optical structure provisioning engine 324 may receive a request and / or instruction from the fiber cross-connect provisioning engine 314. The optical structure provisioning engine 324 may determine whether there are sufficient resources to satisfy the request for the fiber cross-connect service configured in the necessary interconnection facility. In some examples, the optical structure provisioning engine 324 may query one or more components such as the SDN controller 306, the hardware configurator 308, and / or the optical fiber telemetry and analysis data (OFTAD) 326. If there are sufficient resources to supply the requested service, the optical structure provisioning engine 324 may send instructions and / or requests to one or more of the SDN controller 306 and / or the hardware configurator 308 so that the necessary components are configured to supply the requested service. In this way, the optical structure provisioning engine 324 provides the function of selecting a supplier, as well as the form factor for delivering the service. The optical structure provisioning engine 324 also provides a policy manager function to ensure that the service is delivered in the correct order of operation.

[0081] The optical fabric provisioning engine 324 may query and store optical switch fabric telemetry and analytics data (OFTAD) 326 in one or more data repositories. OFTAD 326 may include metrics about the number, type, and definition of the network, optical switch fabric, and resource configurations configured by the NFU 304. OFTAD 326 may include analytics information from the infrastructure data collector 310 based on raw metrics data for resources in a particular service. For example, the analytics information of OFTAD 326 may include historical statistics and / or real-time statistics. OFTAD 326 may also include data describing the use of optical fibers in the optical switch fabric, such as those optical fibers currently being used in optical cross-connects and optical ports of photonic switches.

[0082] like Figure 5As shown in , the SDN controller 306 can configure optical switching fabric resources, such as photonic switches, active panels, etc., which provide a physical infrastructure for end-to-end fiber cross-connection to carry optical signals through interconnection facilities. In some cases, the SDN controller 306 can configure network resources, such as routers, switches, bridges, etc., which provide a physical infrastructure to carry optical signals through interconnection facilities. The hardware configurator 308 can configure hardware resources, such as servers or the above-mentioned network and / or optical switching fabric resources; resources within servers and network resources, including processor allocation, storage allocation; storage equipment; other hardware resources; and software configurations that can be configured to supply services to customers. The infrastructure data collector 310 can collect metrics about the number, type, and definition of network and resource configurations configured by the NFU 304. For example, the infrastructure data collector 310 can monitor and measure metrics of network and optical switching fabric resources and any other resources configured to supply services to customers. The infrastructure data collector 310 can store such metrics in the OFTAD 326.

[0083] In some examples, the programmable network platform 300 can represent an intelligent centralized service delivery and assurance system with the capability of a fault mitigation monitoring / analysis / plane / execution (MAPE) loop that will ensure that the services delivered by the system are guaranteed to comply with the service level agreement for the lifecycle of the service. In some examples, the programmable network platform 300 not only delivers services that can be provided by its own delivery infrastructure, but also has the ability to communicate across other coordination systems to deliver combined similar services. The programmable network platform 300, or more specifically the CNC system 302, can be a central control center for both operational and business-related functions to be performed.

[0084] The NFU 304 and CNC system 302 can also meet the need for a distributed coordination system for creating services and distributing the intelligence for delivering and ensuring optical fiber cross-connect services. The programmable network platform 300 provides the advantage of providing a distributed, horizontally scalable architecture. The CNC 302 and one or more NFUs 304 can provide business service delivery and assurance into two clearly separated functions: (1) CNC - can handle the function of converting business requests into service parameters; (2) NFU - can handle the function of converting service parameters into optical switching fabric parameters and instantiating services.

[0085] Figure 6 is a block diagram illustrating further details of one example of a computing device operating in accordance with one or more techniques of this disclosure. Figure 6A specific example of a server or other computing device 500 including one or more processors 502 for executing a programmable network platform application 524 or any other computing device described herein may be illustrated. Other examples of computing devices 500 may be used in other examples. Although for purposes of example, Figure 6 Although shown as a standalone computing device 500, the programmable network platform application 524 may be distributed among multiple on-premises computing devices, in the cloud, in a hybrid other deployment, and the computing device may be any component or system including one or more processors or other suitable computing environment for executing software instructions, and need not include, for example, Figure 6 504 ; and in some examples, components such as storage device(s) 508 may not be co-located or in the same chassis as other components.

[0086] like Figure 6 As shown in the specific example of , the computing device 500 includes one or more processors 502, one or more input devices 504, one or more communication units 506, one or more output devices 512, one or more storage devices 508, and a user interface (UI) device 510, and a communication unit 506. In one example, the computing device 500 also includes one or more applications 522, (multiple) programmable network platform applications 524 including a fiber cross-connect supply engine 550 and an optical structure supply engine 522, and an operating system 516 executable by the computing device 500. Each of the components 502, 504, 506, 510, and 512 is coupled (physically, communicatively, and / or operationally) for inter-component communication. In some examples, the communication channel 514 may include a system bus, a network connection, an inter-process communication data structure, or any other method for communicating data. As an example, the components 502, 504, 506, 510, and 512 may be coupled by one or more communication channels 514.

[0087] In one example, processor 502 is configured to implement functional and / or process instructions for execution within computing device 500. For example, processor 502 may be capable of processing instructions stored in storage device 508. Examples of processor 502 may include any one or more of the following: a microprocessor, a controller, a digital signal processor (DSP), an application specific integrated circuit (ASIC), a field programmable gate array (FPGA), or an equivalent discrete or integrated logic circuit device.

[0088] One or more storage devices 508 may be configured to store information within the computing device 500 during operation. In some examples, the storage facility 508 is described as a computer-readable storage medium. In some examples, the storage device 508 is a temporary memory, meaning that the primary purpose of the storage device 508 is not long-term storage. In some examples, the storage facility 508 is described as a volatile memory, meaning that the storage device 508 does not maintain the stored contents when the computer is turned off. Examples of volatile memory include random access memory (RAM), dynamic random access memory (DRAM), static random access memory (SRAM), and other forms of volatile memory known in the art. In some examples, the storage device 508 is used to store program instructions for execution by the processor 502. In one example, the storage device 508 is used by software or applications running on the computing device 500 to temporarily store information during program execution.

[0089] In some examples, storage device 508 also includes one or more computer-readable storage media. Storage device 508 can be configured to store a larger amount of information than volatile memory. Storage device 508 can also be configured for long-term storage of information. In some examples, storage device 508 includes a non-volatile storage element. Examples of such non-volatile storage elements include a magnetic hard disk, an optical disk, a floppy disk, a flash memory, or an electrically programmable memory (EPROM) or an electrically erasable programmable (EEPROM) memory.

[0090] In some examples, computing device 500 also includes one or more communication units 506. In one example, computing device 500 utilizes communication unit 506 to communicate with external devices via one or more networks (such as, one or more wired / wireless / mobile networks). Communication unit 506 may include a network interface card such as an Ethernet card, an optical transceiver, a radio frequency transceiver, or other types of devices that can send and receive information. Other examples of such network interfaces may include 3G and WiFi radios. In some examples, computing device 500 uses communication unit 506 to communicate with external devices.

[0091] In one example, computing device 500 also includes one or more user interface devices 510. In some examples, user interface device 510 is configured to receive input from a user through tactile, audio, or video feedback. Examples of (multiple) user interface devices 510 include a presence-sensitive display, a mouse, a keyboard, a voice response system, a video camera, a microphone, or any other type of device for detecting commands from a user. In some examples, the presence-sensitive display includes a touch-sensitive screen.

[0092] One or more output devices 512 may also be included in the computing device 500. In some examples, the output device 512 is configured to provide output to the user using tactile, audio, or video stimulation. In one example, the output device 512 includes a presence-sensitive display, a sound card, a video graphics adapter card, or any other type of device for converting signals into an appropriate form understandable to a human or machine. Additional examples of output devices 512 include speakers, cathode ray tube (CRT) monitors, liquid crystal displays (LCDs), or any other type of device that can generate understandable output to a user.

[0093] Computing device 500 may include operating system 516. In some examples, operating system 516 controls the operation of components of computing device 500. For instance, in one example, operating system 516 facilitates communication of one or more applications 522 and programmable network platform application(s) 524 with processor 502, communication unit 506, storage device 508, input device 504, user interface device 510, and output device 512.

[0094] Application 522 and programmable network platform application(s) 524 may also include program instructions and / or data executable by computing device 500. Example programmable network platform application(s) 524 executable by computing device 500 may include optical cross-connect provisioning engine 550 and / or optical fabric provisioning engine 552, each illustrated with dashed lines to indicate that these engines may or may not be executable by any given example of computing device 500.

[0095] The fiber cross-connect provisioning engine 550 may include instructions for causing the computing device 500 to perform one or more of the operations and actions described in this disclosure with respect to the fiber cross-connect provisioning engine 314. The optical fabric provisioning engine 552 may include instructions for causing the computing device 500 to perform one or more of the operations and actions described in this disclosure with respect to the optical fabric provisioning engine 324.

[0096] Figure 7 is a flow chart illustrating an example mode of operation for providing a fiber cross-connect with an interconnect system including cascaded optical switches according to one or more aspects of the present disclosure. Figures 1 to 3 The interconnection system 2 is described Figure 7 ,but Figure 7 Other examples of interconnect systems described in this disclosure may be applicable.

[0097] A customer may request to provision cross-connected optical fiber at a selected interconnect service level (e.g., an SLA of less than 30 minutes or an SLA of less than 24 hours) (702). The PNP 3 may receive the request and determine whether the selected / requested service level is accelerated (e.g., an SLA of less than 30 minutes) or not accelerated (e.g., an SLA of less than 24 hours) (704). If the requested service is not accelerated (the no branch at 704), the PNP 3 may determine whether a slow optical switch 16 port is available (706). If the port is unavailable (the no branch at 706), the PNP 3 may re-provision the slow optical switch to reconnect at least one port from the fast switch, such as provisioning an unused port that is connected to a port pre-wired to the fast optical switch (708). For example, a first number of ports of the slow optical switch 16 may be pre-wired to the fast optical switch, and a second number of ports of the slow optical switch 16 may be configured to provision optical fiber cross-connects using the ports of the first number of ports, such as to switch between ports pre-wired to the fast optical switch. The third number of ports of the slow optical switch may be configured to provision optical fiber cross-connects using only the slow optical switch, e.g., only between ports of the slow optical switch for an SLA of less than 24 hours. At (708), if all ports of the third number of ports are used, the PNP 3 may release one port of the second number of ports to be used as one port of the third number of ports, e.g., to reconnect another port (e.g., port 26) of the slow optical switch 16 instead of a port (e.g., port 22) of the slow optical switch prewired to the fast optical switch. In some examples, the customer may select a port while selecting / requesting a service level (e.g., unaccelerated service (SLA of less than 24 hours)). The selected port may be pre-provisioned in the slow optical switch 16 to be connected to an output port of the slow optical switch 16, which is prewired to the fast switch. The PNP 3 may determine that the selected port is provisioned to be connected to the fast switch, and may re-provision the selected port within the slow optical switch 16 to connect to a different output port of the slow optical switch 16, e.g., to meet the unaccelerated service.

[0098] In this way, when the selected SLA does not require fast switching, the PNP 3 can avoid unnecessarily occupying the ports of the fast optical switch. In some examples, the PNP 3 can determine the configuration data for the fiber cross-connection based on the customer selection / request, the port and switch availability of the cascade optical switch 10, and the pre-wiring of the ports of the cascade optical switch 10 (e.g., to the customer space 4), and the PNP 3 can send the configuration data to the cascade optical switch 10. The slow optical switch 16 can then receive the configuration data to modify the switching configuration to reconfigure the fiber cross-connection in the optical switch structure, which only includes the slow switch 16, for example, and does not include the fast switch 12, the fast switch 14, or the ports of the slow switch 16 pre-wired to the fast optical switch 12, the fast optical switch 14. Therefore, the slow optical switch 16 is provisioned with fiber cross-connections in a manner that meets the currently selected / requested SLA of less than 24 hours. The PNP 3 can then, for example, update the cross-connection database (710) with the port data of the re-provisioned ports.

[0099] However, if the slow switch port is available (yes branch at 706), the PNP 3 does not need to reconfigure the cascade optical switch 10 to disconnect the port of the fast switch. The PNP 3 can determine the configuration data for the fiber cross-connect based on the customer selection / request, the port and switch availability of the cascade optical switch 10, and the pre-wiring of the port of the cascade optical switch 10 (e.g., to the customer space 4), and the PNP 3 can send the configuration data to the slow optical switch 16 and the fast optical switch 12, the fast optical switch 14. The slow optical switch 16 can then receive the configuration data to modify the switching configuration to reconfigure the fiber cross-connect in the optical switch fabric, the fiber cross-connect only including the slow switch 16, for example, and not including the fast switch 12, the fast switch 14 or the port of the optical switch 16 pre-wired to the fast optical switch 12, the fast optical switch 14. Therefore, the slow optical switch 16 is provisioned with the fiber cross-connect in a manner that meets the currently requested SLA of less than 24 hours (712). PNP 3 may then, for example, update the cross-connect database with the port data for the re-provisioned port (710).

[0100] If the requested fiber cross-connect service is accelerated (Yes Branch at 704), the PNP 3 may determine whether the fast optical switch 12 port is available (714). If the port is available (Yes Branch at 714), the fast optical switch 12 will provision the fiber cross-connect (716). For example, the PNP 3 may determine configuration data for the fiber cross-connect based on the customer request, the port and switch availability of the cascaded optical switch 10, and the pre-wiring of the port of the cascaded optical switch 10 (e.g., to the customer space 4), and the PNP 3 may send the configuration data to the switch of the cascaded optical switch 10. The slow optical switch 16 and / or the fast optical switch 12 may then receive the configuration data to modify the switching configuration to reconfigure the fiber cross-connect in the optical switch fabric, the fiber cross-connect including the fast optical switch 12 and including at least one of the pre-wiring optical fiber 42A to the pre-wiring optical fiber 42C and the pre-wiring optical fiber 44A to the pre-wiring optical fiber 44C. As described herein with respect to the slow optical switch and the fast optical switch, receiving the configuration data can cause the fast switch and / or the slow optical switch to configure themselves to switch according to the received configuration data, e.g., automatically provision connections between appropriate input ports and output ports per the received configuration data. Thus, the slow optical switch 16 and the fast optical switch 12 are provisioned with fiber cross-connects (716), e.g., fiber cross-connects 50, fiber cross-connects 60, or fiber cross-connects 70 in a manner that satisfies the requested SLA of less than 30 minutes. The PNP 3 can then, e.g., update the cross-connect database (710) with the port data of the re-provisioned ports.

[0101] If the port of the fast optical switch 12 is not available (the No branch at 714), then the cascade optical switch 10 will search for an available fast switch (718), such as the fast switch 14. The PNP 3 can determine whether the port of the fast optical switch 14 is available (720). If the port is available (the Yes branch at 720), the PNP 3 will use the slow optical switch 16 and the fast optical switch 14 to provision a fiber cross-connect (722). For example, the PNP 3 may determine configuration data for a fiber cross-connect based on a customer request, port and switch availability of the cascade optical switch 10, and pre-wiring of the ports of the cascade optical switch 10 (e.g., to the customer space 4), and the PNP 3 may send the configuration data to the slow optical switch 16 and / or the fast optical switch 14, which modifies the switching configuration to configure a fiber cross-connect in an optical switching fabric that includes the fast optical switch 14 and includes at least one of the pre-wiring optical fiber 42D to the pre-wiring optical fiber 42F and / or the pre-wiring optical fiber 44D to the pre-wiring optical fiber 44F. In some examples, the PNP 3 may be configured to prioritize requests. For example, the slow optical switch 16 may have a queue for requesting and / or updating fiber cross-connects. SLA fiber cross-connect requests of less than 30 minutes may have a high priority, and the PNP 3 may send configuration data to the slow optical switch 16 that includes a priority level and / or a command to prioritize requests within the queue for the slow optical switch 16. Therefore, the slow optical switch 16 and the fast optical switch 14 are configured to implement the fiber cross-connect in a manner that meets the requested SLA of less than 30 minutes (720).The PNP 3, for example, can then update the cross-connect database (710) with the port data of the re-provisioned ports.

[0102] If a port of the fast optical switch 14 is not available (no branch at 720), the PNP 3 will output a message indicating that no fast switch is available (724). The network operation center (NOC) can optionally notify the requesting customer that an accelerated SLA of less than 30 minutes is not available and the cross-connect service will be completed as un-accelerated (726), such as an SLA of less than 24 hours. The slow optical switch 16 can then provision a fiber cross-connect (728), for example, as described above at (712).

[0103] Figure 8 is a flow chart illustrating an example mode of operation for providing a fiber cross-connect with an interconnect system including cascaded optical switches according to one or more aspects of the present disclosure. Figure 3 Description of the interconnection system Figure 8 but Figure 8Other examples of interconnect systems described in this disclosure may be applied.

[0104] PNP 3 may determine that network / signal / data traffic is down (802), such as a port or fast optical switch is down and / or not functioning. In some examples, PNP 3 may receive a customer report (e.g., a manual report or an automatic report by a customer device) that network / signal / data traffic is down. PNP 3 may then determine whether a fast optical switch inlet port (804) is down or a fast optical switch outlet port is down (808). If the fast optical switch inlet port is down (the "yes" branch at 804), PNP 3 may output an error message (806), and the network interconnection service operator may respond accordingly, for example, to repair the port and / or switch. If the fast optical switch inlet port is not down (the "no" branch at 804) and the fast optical switch outlet port is not down (the "no" branch at 808), PNP 3 may output an error message (810), and the network interconnection service operator may respond accordingly, for example, to troubleshoot and / or determine the cause of the network / signal / data outage.

[0105] If the fast optical switch inlet port is down (YES Truncation at 808), PNP 3 may determine whether a port in the same fast optical switch is available (812). For example, PNP 3 may determine that port 32A of the fiber cross-connect 60 supplied by the fast optical switch 12 is down at (808), and may determine that port 32B is available (YES Truncation at 812). PNP 3 may determine configuration data for the fiber cross-connect 62, and PNP 3 may send the configuration data to the cascade optical switch 10. The slow optical switch 16 and / or the fast optical switch 12 may receive the configuration data to modify the switch configuration to reconfigure the fiber cross-connect in the optical switch fabric to the fiber cross-connect 62, for example, including port 32B and at least one of the pre-wired optical fibers 42B and / or the pre-wired optical fibers 44B. The slow optical switch 16 may then provision (or re-provision) a connection from port 20A to port 22B (814), and the PNP 3 may then update the cross-connect database (815), for example, with the port data for the re-provisioned port.

[0106] If the port of the fast optical switch 12 is not available (the No branch at 812), the cascade optical switch 10 will search for an available fast switch (816), such as the fast switch 14. The PNP 3 may determine whether the fast optical switch 14 port is available (818). If the port is available (the Yes branch at 818), the slow optical switch 16 and the fast optical switch 14 will provision a fiber cross-connection (820). The PNP 3 may determine configuration data for a new fiber cross-connection, and the PNP 3 may send the configuration data to the cascade optical switch 10. The slow optical switch 16 and / or the fast optical switch 14 may receive the configuration data to modify the switching configuration to reconfigure the fiber cross-connection in the optical switch fabric to include a fiber cross-connection (not shown) of the fast optical switch 14, such as including the port 32C and the pre-wired optical fiber 42C and / or at least one of the pre-wired optical fiber 44C or the pre-wired optical fiber 44D. Slow optical switch 16 may then provision (or re-provision) the connection from port 20A to port 22C, and PNP 3 may then update the cross-connect database (815), for example, with the port data for the re-provisioned port.

[0107] If the port of the fast optical switch 14 is not available (the NO branch at 818), the cascade optical switch 10 may output a fast switch full message and / or notification (822), and the PNP 3 may determine whether the fast optical switch P port is available (824). If the port is available (the YES branch at 824), the slow optical switch 16 and the fast optical switch P will provision the fiber cross-connect (826). The PNP 3 may determine the configuration data for the fiber cross-connect 64, and the PNP 3 may send the configuration data to the cascade optical switch 10. The slow optical switch 16 and / or the fast optical switch P may receive the configuration data to modify the switch configuration to reconfigure the fiber cross-connect 64 in the optical switch fabric to include the fiber cross-connect of the fast optical switch P, for example, including the port 32X and the pre-wired optical fiber 42X and / or at least one of the pre-wired optical fiber 44X or the pre-wired optical fiber 44Y. Slow optical switch 16 may then provision (or re-provision) a connection from port 20A to port 22E, and PNP 3 may then update the cross-connect database (815), for example, with the port data for the re-provisioned port.

[0108] If a port of the fast optical switch P is not available (NO branch at 824), the cascade optical switch 10 can output a fast switch and / or protection fast switch full message and / or notification (828), and the PNP 3 can re-provision the slow optical switch 16 to disconnect at least one port from the fast switch, for example, provision an unused port that is connected to a port pre-wired to the fast optical switch (830) such as similar to (708) described above, and then the slow optical switch 16 can provision the fiber cross-connect 66 to connect port 20A to port 26B.

[0109] This article describes the following examples.

[0110] Example 1: A cascaded optical switch for an optical switching structure of a data center, the cascaded optical switch comprising: a fast optical switch having an input port and an output port; a slow optical switch having an input port and an output port, wherein a switching time of the slow optical switch is longer than a switching time of the fast optical switch; a first pre-wiring optical fiber, the first pre-wiring optical fiber connecting a first port, which is one of the output ports of the slow optical switch, to a second port, which is one of the input ports of the input ports of the fast optical switch; and a second pre-wiring optical fiber, the second pre-wiring optical fiber connecting a third port, which is one of the output ports of the fast optical switch, to a fourth port, which is one of the input ports of the input ports of the slow optical switch, wherein the fast optical switch or the slow optical switch is configured to receive configuration data to modify a switching configuration to configure a fiber cross-connection in the optical switching structure, the fiber cross-connection comprising at least one of the first pre-wiring optical fiber or the second pre-wiring optical fiber.

[0111] Example 2: The cascaded optical switch of Example 1, wherein a plurality of pre-wired optical fibers connect corresponding output ports of one or more customer spaces to corresponding input ports of a slow optical switch, wherein the number of input ports of the slow optical switch connected to the output ports of the customer spaces is greater than the total number of input ports of the fast optical switch.

[0112] Example 3: The cascaded optical switch of Example 1 or Example 2, wherein a fifth port that is one of the input ports of the slow optical switch is pre-wired to a first output port of a first customer space, wherein a sixth port that is a different one of the input ports of the slow optical switch is pre-wired to a second output port of a second customer space, and wherein the configuration data configures the slow optical switch from switching from the fifth port to the first port to switching from the sixth port to the first port.

[0113] Example 4: The cascaded optical switch of any one of Examples 1 to 3, wherein the fiber cross-connect is a first fiber cross-connect, the first fiber cross-connect includes at least one of the first pre-wired optical fiber or the second pre-wired optical fiber, and has been requested to meet a first service level agreement with a first fiber cross-connect reconfiguration speed, wherein the slow optical switch is configured to receive configuration data to modify the switch configuration to configure a second fiber cross-connect in the optical switch structure, the second fiber cross-connect does not include any of the first pre-wired optical fiber or the second pre-wired optical fiber, wherein the second fiber cross-connect has been requested to meet a second service level agreement with a second fiber cross-connect reconfiguration speed, wherein the first fiber cross-connect reconfiguration speed is faster than the second fiber cross-connect reconfiguration speed.

[0114] Example 5: The cascaded optical switch of Example 4 further includes a third pre-wiring optical fiber, which connects a fifth port that is one of the input ports of the slow optical switch to an output port of the customer space, wherein the first optical fiber cross-connection and the second optical fiber cross-connection include the third pre-wiring optical fiber.

[0115] Example 6: The cascaded optical switch of any one of Examples 1 to 5, further comprising a third pre-wiring optical fiber, the third pre-wiring optical fiber connecting a fifth port, which is one of the output ports of the slow optical switch, to a sixth port, which is one of the input ports of the fast optical switch, wherein the fast optical switch or the slow optical switch is configured to receive configuration data to modify the switching configuration to configure the optical fiber cross-connection in the optical switching structure to include the third pre-wiring optical fiber and the second pre-wiring optical fiber.

[0116] Example 7: The cascaded optical switch of any one of Examples 1 to 6, wherein the fast switch is a first fast switch, and the cascaded optical switch further comprises: a second fast optical switch having an input port and an output port; and a third pre-wiring optical fiber, the third pre-wiring optical fiber connecting a fifth port, which is one of the output ports of the slow optical switch, to a sixth port, which is one of the input ports of the input ports of the second fast optical switch; and a fourth pre-wiring optical fiber, the fourth pre-wiring optical fiber connecting a seventh port, which is one of the output ports of the second fast optical switch, to an eighth port, which is one of the input ports of the input ports of the slow optical switch; wherein the second fast optical switch or the slow optical switch is configured to receive configuration data to modify the switching configuration to configure a fiber cross-connection in the optical switching structure, the fiber cross-connection comprising at least one of the third pre-wiring optical fiber or the fourth pre-wiring optical fiber.

[0117] Example 8: A method, comprising: receiving configuration data by a slow optical switch of a cascaded optical switch or by a fast optical switch of the cascaded optical switch to modify a switching configuration to configure a fiber cross-connection in an optical switching structure, the fiber cross-connection comprising at least one of a first pre-wired optical fiber or a second pre-wired optical fiber, wherein the fast optical switch comprises an input port and an output port, wherein the slow optical switch comprises an input port and an output port, wherein a switching time of the slow optical switch is longer than a switching time of the fast optical switch, wherein the first pre-wired optical fiber connects a first port as one of the output ports of the slow optical switch to a second port as one of the input ports of the fast optical switch, wherein the second pre-wired optical fiber connects a third port as one of the output ports of the fast optical switch to a fourth port as one of the input ports of the slow optical switch.

[0118] Example 9: The method of Example 8, wherein multiple pre-wired optical fibers connect corresponding output ports of one or more customer spaces to corresponding input ports of a slow optical switch, wherein the number of input ports of the slow optical switch connected to the output ports of the customer spaces is greater than the total number of input ports of the fast optical switch.

[0119] Example 10: The method of Example 8 or Example 9, wherein the fiber cross-connection includes a fifth port, the fifth port is an input port of the slow optical switch, and the fifth port is pre-wired to a first output port of the first customer space, and the method further includes: the slow optical switch receives configuration data to modify the switching configuration to configure the fiber cross-connection in the optical switching structure to include a sixth port, the sixth port is an input port of the slow optical switch different from the fifth port, wherein the sixth port is pre-wired to a second output port of the second customer space, and wherein the configuration data configures the slow optical switch from switching from the fifth port to the first port to switching from the sixth port to the first port.

[0120] Example 11: The method of any one of Examples 8 to 10, wherein the fiber cross-connection is a first fiber cross-connection, the first fiber cross-connection includes at least one of the first pre-wiring optical fiber or the second pre-wiring optical fiber, and has been requested to meet a first service level agreement with a first fiber cross-connection reconfiguration speed, the method further comprising: receiving configuration data by a slow optical switch to modify a switching configuration to configure a second fiber cross-connection in the optical switching structure, the second fiber cross-connection does not include any of the first pre-wiring optical fiber or the second pre-wiring optical fiber, wherein the second fiber cross-connection has been requested to meet a second service level agreement with a second fiber cross-connection reconfiguration speed, wherein the first fiber cross-connection reconfiguration speed is faster than the second fiber cross-connection reconfiguration speed; and switching by the slow optical switch between supplying the first fiber cross-connection and the second fiber cross-connection.

[0121] Example 12: The method of Example 11, wherein a first portion of the input ports of the slow switch are supplied to be connected to the input ports of the fast optical switch, wherein a second portion of the input ports of the slow optical switch are supplied to be connected to the output ports of the slow optical switch, the method further comprising: determining that the input ports of the second portion of the input ports are unavailable before supplying a switch between the first optical fiber cross-connection and the second optical fiber cross-connection; resupplying a fifth port of the input ports of the first portion of the input ports of the slow optical switch to be connected to one of the output ports of the slow optical switch; and configuring the second optical fiber cross-connection to include the fifth port.

[0122] Example 13: The method of any one of Examples 8 to 12, wherein the fast optical switch is a first fast optical switch, and the method further includes: before supplying the slow optical switch and the fast optical switch, determining that the second port is unavailable; determining that a fifth port, which is an input port of the second fast optical switch including an input port and an output port, is available; and re-supplying the slow optical switch to configure the optical fiber cross-connection to include a third pre-wiring optical fiber or a fourth pre-wiring optical fiber, wherein the switching time of the slow optical switch is longer than the switching time of the second fast optical switch, wherein the third pre-wiring optical fiber connects the fifth port, which is one of the output ports of the slow optical switch, to the sixth port, which is one of the input ports of the input ports of the fast optical switch, and wherein the fourth pre-wiring optical fiber connects the seventh port, which is one of the output ports of the fast optical switch, to the eighth port, which is one of the input ports of the input ports of the slow optical switch.

[0123] Example 14: The method of any one of Examples 8 to 13, the method further comprising: determining that the second port or the third port is not working; if the second port is not working, determining that a fifth port, which is one of the input ports of the fast optical switch, is available, wherein the fifth port is connected to a sixth port, which is one of the output ports of the slow optical switch, through a third pre-wiring optical fiber; if the third port is not working, determining that a seventh port, which is one of the output ports of the fast optical switch, is available, wherein the seventh port is connected to an eighth port, which is one of the input ports of the slow optical switch, through a fourth pre-wiring optical fiber; receiving configuration data by the slow optical switch or the fast optical switch to modify the switching configuration to configure the optical fiber cross-connection in the optical switching structure, if the second port is not working, the optical fiber cross-connection includes the third pre-wiring optical fiber, and if the third port is not working, the optical fiber cross-connection includes the fourth pre-wiring optical fiber; and supplying the slow optical switch and the fast optical switch according to the received configuration data to configure the optical fiber cross-connection to include at least one of the third pre-wiring optical fiber or the fourth pre-wiring optical fiber.

[0124] Example 15: The method of any one of Examples 8 to 14, wherein the fast optical switch is a first fast optical switch, and the method further includes: determining that the second port or the third port is not working; determining that a fifth port, which is an input port of the second fast optical switch, is available, wherein the fifth port is connected to a sixth port, which is one of the output ports of the slow optical switch, through a third pre-wiring optical fiber, wherein a seventh port, which is one of the output ports of the second fast optical switch, is connected to an eighth port, which is one of the input ports of the slow optical switch, through a fourth pre-wiring optical fiber; receiving configuration data by the slow optical switch or the fast optical switch to modify the switching configuration to configure a fiber cross-connection in the optical switching structure, the fiber cross-connection including at least one of the third pre-wiring optical fiber or the fourth pre-wiring optical fiber; and supplying the slow optical switch and the fast optical switch according to the received configuration data to configure the fiber cross-connection to include at least one of the third pre-wiring optical fiber or the second pre-wiring optical fiber.

[0125] Example 16: The method of any one of Examples 8 to 15, further comprising: determining that the second port or the third port is not working; determining that no input port of the fast optical switch is available; receiving configuration data by the slow optical switch or the fast optical switch to modify the switching configuration to configure the optical fiber cross-connection in the optical switching structure to not include the first pre-wiring optical fiber or the second pre-wiring optical fiber; and switching by the slow optical switch to supply the optical fiber cross-connection to not include the first pre-wiring optical fiber or the second pre-wiring optical fiber.

[0126] Example 17: A system comprising: a programmable network platform configured to determine configuration data to modify a switching configuration to configure a fiber cross-connection in an optical switching structure; and a cascaded optical switch for an optical switching structure of a data center, the cascaded optical switch comprising: a fast optical switch having an input port and an output port; a slow optical switch having an input port and an output port, wherein a switching time of the slow switch is longer than a switching time of the fast optical switch; a first pre-wiring optical fiber, the first pre-wiring optical fiber connecting a first port, which is one of the output ports of the slow optical switch, to a second port, which is one of the input ports of the input ports of the fast optical switch; and a second pre-wiring optical fiber, the second pre-wiring optical fiber connecting a third port, which is one of the output ports of the fast optical switch, to a fourth port, which is one of the input ports of the input ports of the slow optical switch, wherein the fast optical switch or the slow optical switch is configured to receive configuration data from the programmable network platform to modify the switching configuration to configure a fiber cross-connection in the optical switching structure, the fiber cross-connection comprising at least one of the first pre-wiring optical fiber or the second pre-wiring optical fiber.

[0127] Example 18: The system of Example 17, wherein the programmable network platform is configured to determine configuration data based on a customer request for a fiber optic cross-connection with a first service level agreement having a first fiber optic cross-connection reconfiguration speed or with a second service level agreement having a second fiber optic cross-connection reconfiguration speed, wherein the first fiber optic cross-connection reconfiguration speed is faster than the second fiber optic cross-connection reconfiguration speed.

[0128] Example 19: The system of Example 17 or Example 18 further includes a plurality of pre-wired optical fibers, each connecting an output port of one or more customer spaces to a different input port of a slow optical switch, wherein the number of input ports of the slow optical switch connected to the output ports of the customer spaces is greater than the total number of input ports of the fast optical switch.

[0129] Example 20: The method of any one of Examples 17 to 19, wherein a fifth port that is an input port of the slow optical switch is pre-wired to a first output port of a first customer space, wherein a sixth port that is a different input port of the slow optical switch is pre-wired to a second output port of a second customer space, wherein the slow optical switch is configured to switch between connecting the fifth port and the first port and connecting the sixth port and the first port.

[0130] The techniques described herein may be implemented in hardware, software, firmware, or any combination thereof. The various features described as modules, units, or components may be implemented together in an integrated logic device or separately as discrete but interoperable logic devices or other hardware devices. In some cases, the various features of the electronic circuit device may be implemented as one or more integrated circuit devices, such as an integrated circuit chip or chipset.

[0131] If implemented in hardware, the disclosure may be directed to an apparatus such as a processor or an integrated circuit device (such as an integrated circuit chip or chipset). Alternatively or additionally, if implemented in software or firmware, the technology may be implemented at least in part by a computer-readable data storage medium including instructions that, when executed, cause the processor to perform one or more of the above methods. For example, a computer-readable data storage medium may store such instructions for execution by a processor.

[0132] The computer-readable medium may form part of a computer program product, which may include packaging materials. The computer-readable medium may include computer data storage media, such as random access memory (RAM), read-only memory (ROM), non-volatile random access memory (NVRAM), electrically erasable programmable read-only memory (EEPROM), flash memory, magnetic or optical data storage media, etc. In some examples, the article of manufacture may include one or more computer-readable storage media.

[0133] In some examples, computer-readable storage media may include non-transitory media. The term "non-transitory" may indicate that the storage medium is not embodied in a carrier wave or propagating signal. In some examples, non-transitory storage media may store data that may change over time (e.g., in RAM or cache memory).

[0134] The code or instructions may be software and / or firmware executed by a processing circuit device including one or more processors, such as one or more digital signal processors (DSPs), general-purpose microprocessors, application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other equivalent integrated or discrete logic circuit devices. Thus, the term "processor" as used herein may refer to any of the foregoing structures or any other structure suitable for implementing the techniques described herein. Furthermore, in some aspects, the functionality described in the present disclosure may be provided within a software module or a hardware module.

Claims

1. A cascade optical switch for an optical switching structure of a data center, the cascade optical switch comprising: A fast optical switch having an input port and an output port; a slow optical switch having an input port and an output port, wherein a switching time of the slow optical switch is longer than a switching time of the fast optical switch; a first pre-wiring optical fiber connecting a first port, which is one of the output ports of the slow optical switch, to a second port, which is one of the input ports of the fast optical switch; as well as a second pre-wiring optical fiber connecting a third port, which is one of the output ports of the fast optical switch, to a fourth port, which is one of the input ports of the slow optical switch, The fast optical switch or the slow optical switch is configured to receive configuration data to modify a switch configuration to configure a fiber cross-connection in the optical switch fabric, the fiber cross-connection comprising at least one of the first pre-wiring optical fiber or the second pre-wiring optical fiber.

2. The cascaded optical switch of claim 1 , wherein a plurality of pre-wired optical fibers connect corresponding output ports of one or more customer spaces to corresponding input ports of the slow optical switch, wherein the number of input ports of the slow optical switch connected to the output ports of the customer spaces is greater than the total number of input ports of the fast optical switch.

3. The cascaded optical switch according to claim 1 or claim 2, wherein a fifth port, which is one of the input ports of the slow optical switch, is pre-wired to a first output port of a first customer space, wherein a sixth port, which is a different one of the input ports of the slow optical switch, is pre-wired to a second output port of a second customer space, and wherein the configuration data configures the slow optical switch to switch from the fifth port to the first port to switch from the sixth port to the first port.

4. The cascade optical switch according to any one of claims 1 to 3, wherein the optical fiber cross-connect is a first optical fiber cross-connect, the first optical fiber cross-connect includes at least one of the first pre-wiring optical fiber or the second pre-wiring optical fiber, and has been requested to meet a first service level agreement having a first optical fiber cross-connect reconfiguration speed, wherein the slow optical switch is configured to receive configuration data to modify the switch configuration to configure a second optical fiber cross-connection in the optical switch fabric, the second optical fiber cross-connection not including either the first pre-wiring optical fiber or the second pre-wiring optical fiber, wherein the second optical fiber cross-connection has been requested to meet a second service level agreement having a second optical fiber cross-connection reconfiguration speed, The first optical fiber cross-connection reconfiguration speed is faster than the second optical fiber cross-connection reconfiguration speed.

5. The cascade optical switch according to claim 4, further comprising: A third pre-wiring optical fiber connects a fifth port, which is one of the input ports of the slow optical switch, to an output port of a customer space, wherein the first optical fiber cross-connect and the second optical fiber cross-connect include the third pre-wiring optical fiber.

6. The cascade optical switch according to any one of claims 1 to 5, further comprising: a third pre-wiring optical fiber connecting a fifth port, which is one of the output ports of the slow optical switch, to a sixth port, which is one of the input ports of the fast optical switch, The fast optical switch or the slow optical switch is configured to receive the configuration data to modify the switch configuration to configure the optical fiber cross-connection in the optical switch fabric to include the third pre-wiring optical fiber and the second pre-wiring optical fiber.

7. The cascade optical switch according to any one of claims 1 to 6, wherein the fast switch is a first fast switch, and the cascade optical switch further comprises: a second fast optical switch having an input port and an output port; as well as a third pre-wiring optical fiber connecting a fifth port, which is one of the output ports of the slow optical switch, to a sixth port, which is one of the input ports of the second fast optical switch; a fourth pre-wiring optical fiber connecting a seventh port, which is one of the output ports of the second fast optical switch, to an eighth port, which is one of the input ports of the slow optical switch; The second fast optical switch or the slow optical switch is configured to receive configuration data to modify a switching configuration to configure a fiber cross-connection in the optical switching structure, wherein the fiber cross-connection includes at least one pre-wiring optical fiber of the third pre-wiring optical fiber or the fourth pre-wiring optical fiber.

8. A method comprising: receiving configuration data by a slow optical switch of the cascaded optical switches or by a fast optical switch of the cascaded optical switches to modify a switch configuration to configure a fiber cross-connection in the optical switch fabric, the fiber cross-connection comprising at least one of the first pre-wired optical fiber or the second pre-wired optical fiber, The fast optical switch comprises an input port and an output port, wherein the slow optical switch comprises an input port and an output port, wherein a switching time of the slow optical switch is longer than a switching time of the fast optical switch, wherein the first pre-wiring optical fiber connects a first port, which is one of the output ports of the slow optical switch, to a second port, which is one of the input ports of the fast optical switch, The second pre-wiring optical fiber connects a third port, which is one of the output ports of the fast optical switch, to a fourth port, which is one of the input ports of the slow optical switch.

9. The method of claim 8, wherein a plurality of pre-wired optical fibers connect corresponding output ports of one or more customer spaces to corresponding input ports of the slow optical switch, wherein the number of input ports of the slow optical switch connected to the output ports of the customer spaces is greater than the total number of input ports of the fast optical switch.

10. The method of claim 8 or claim 9, wherein the optical fiber cross-connect comprises a fifth port, the fifth port being an input port of the slow optical switch, the fifth port being pre-wired to a first output port of a first customer space, the method further comprising: receiving, by the slow optical switch, the configuration data to modify a switch configuration to configure the optical fiber cross-connect in the optical switch fabric to include a sixth port, the sixth port being an input port of the slow optical switch different from the fifth port, wherein the sixth port is prewired to a second output port of a second customer space, The configuration data configures the slow optical switch to switch from the sixth port to the first port instead of switching from the fifth port to the first port.

11. The method according to any one of claims 8 to 10, wherein the optical fiber cross-connection is a first optical fiber cross-connection, the first optical fiber cross-connection comprising at least one of the first pre-wiring optical fiber or the second pre-wiring optical fiber, and has been requested to meet a first service level agreement having a first optical fiber cross-connection reconfiguration speed, the method further comprising: receiving, by the slow optical switch, configuration data to modify the switch configuration to configure a second optical fiber cross-connection in the optical switch fabric, the second optical fiber cross-connection not including either the first pre-wired optical fiber or the second pre-wired optical fiber, wherein the second optical fiber cross-connection has been requested to satisfy a second service level agreement having a second optical fiber cross-connection reconfiguration speed, wherein the first optical fiber cross-connection reconfiguration speed is faster than the second optical fiber cross-connection reconfiguration speed; as well as The slow optical switch switches between supplying the first optical fiber cross-connect and the second optical fiber cross-connect.

12. The method of claim 11, wherein a first portion of the input ports of the slow switch are supplied to be connected to input ports of the fast optical switch, wherein a second portion of the input ports of the slow optical switch are supplied to be connected to output ports of the slow optical switch, the method further comprising: Prior to provisioning a switch between the first fiber cross-connect and the second fiber cross-connect, determining that an input port of the second portion of input ports is unavailable; resupplying a fifth port of the first part of the input ports of the slow optical switch as an output port connected to one of the output ports of the slow optical switch; as well as The second fiber optic cross-connect is configured to include the fifth port.

13. The method according to any one of claims 8 to 12, wherein the fast optical switch is a first fast optical switch, the method further comprising: Before provisioning the slow optical switch and the fast optical switch, determining that the second port is unavailable; determining that a fifth port, which is an input port of a second fast optical switch including an input port and an output port, is available; as well as re-provisioning the slow optical switch to configure the optical fiber cross-connect to include a third pre-wiring optical fiber or a fourth pre-wiring optical fiber, wherein the switching time of the slow optical switch is longer than the switching time of the second fast optical switch, wherein the third pre-wiring optical fiber connects a fifth port, which is one of the output ports of the slow optical switch, to a sixth port, which is one of the input ports of the fast optical switch, and The fourth pre-wiring optical fiber connects a seventh port, which is one of the output ports of the fast optical switch, to an eighth port, which is one of the input ports of the slow optical switch.

14. The method according to any one of claims 8 to 13, further comprising: determining that the second port or the third port is not working; If the second port is not working, determining that a fifth port, which is one of the input ports of the fast optical switch, is available, wherein the fifth port is connected to a sixth port, which is one of the output ports of the slow optical switch, through a third pre-wired optical fiber; If the third port is not working, determining that a seventh port, which is one of the output ports of the fast optical switch, is available, wherein the seventh port is connected to an eighth port, which is one of the input ports of the slow optical switch, through a fourth pre-wiring optical fiber; receiving configuration data by the slow optical switch or the fast optical switch to modify the switch configuration to configure the optical fiber cross-connection in the optical switch fabric, the optical fiber cross-connection including the third pre-wiring optical fiber if the second port is not working, and the optical fiber cross-connection including the fourth pre-wiring optical fiber if the third port is not working; as well as The slow optical switch and the fast optical switch are provisioned according to the received configuration data to configure the optical fiber cross-connect to include at least one of the third pre-wiring optical fiber or the fourth pre-wiring optical fiber.

15. The method according to any one of claims 8 to 14, wherein the fast optical switch is a first fast optical switch, the method further comprising: determining that the second port or the third port is not working; determining that a fifth port as an input port of a second fast optical switch is available, wherein the fifth port is connected to a sixth port as one of the output ports of the slow optical switch through a third pre-wiring optical fiber, wherein a seventh port as one of the output ports of the second fast optical switch is connected to an eighth port as one of the input ports of the slow optical switch through a fourth pre-wiring optical fiber; receiving configuration data by the slow optical switch or the fast optical switch to modify the switch configuration to configure the optical fiber cross-connection in the optical switch fabric, the optical fiber cross-connection comprising at least one pre-wiring optical fiber of the third pre-wiring optical fiber or the fourth pre-wiring optical fiber; as well as The slow optical switch and the fast optical switch are provisioned according to the received configuration data to configure the optical fiber cross-connect to include at least one of the third pre-routed optical fiber or the second pre-routed optical fiber.

16. The method according to any one of claims 8 to 15, further comprising: determining that the second port or the third port is not working; determining that no input port of the fast optical switch is available; receiving, by the slow optical switch or the fast optical switch, configuration data to modify the switch configuration to configure the optical fiber cross-connect in the optical switch fabric to exclude the first pre-wiring optical fiber or the second pre-wiring optical fiber; as well as Switching is performed by the slow optical switch to supply the optical fiber cross-connect to exclude the first pre-wiring optical fiber or the second pre-wiring optical fiber.

17. A system comprising: a programmable network platform configured to determine configuration data to modify a switch configuration to configure optical fiber cross-connects in an optical switch fabric; as well as A cascade optical switch for an optical switching structure of a data center, the cascade optical switch comprising: A fast optical switch having an input port and an output port; a slow optical switch having an input port and an output port, wherein a switching time of the slow switch is longer than a switching time of the fast optical switch; a first pre-wiring optical fiber connecting a first port, which is one of the output ports of the slow optical switch, to a second port, which is one of the input ports of the fast optical switch; and a second pre-wiring optical fiber connecting a third port, which is one of the output ports of the fast optical switch, to a fourth port, which is one of the input ports of the slow optical switch, The fast optical switch or the slow optical switch is configured to receive the configuration data from the programmable network platform to modify the switching configuration to configure the optical fiber cross-connection in the optical switching structure, the optical fiber cross-connection including at least one pre-wiring optical fiber of the first pre-wiring optical fiber or the second pre-wiring optical fiber.

18. The system of claim 17, wherein the programmable network platform is configured to determine the configuration data based on a customer request for the fiber optic cross-connection, with a first service level agreement having a first fiber optic cross-connection reconfiguration speed or with a second service level agreement having a second fiber optic cross-connection reconfiguration speed, wherein the first fiber optic cross-connection reconfiguration speed is faster than the second fiber optic cross-connection reconfiguration speed.

19. The system of claim 17 or claim 18, further comprising a plurality of pre-wired optical fibers, each connecting an output port of one or more customer spaces to a different input port of the slow optical switch, wherein the number of input ports of the slow optical switch connected to the output ports of the customer spaces is greater than the total number of input ports of the fast optical switch.

20. The system of any one of claims 17 to 19, wherein a fifth port being an input port of the slow optical switch is prewired to a first output port of a first customer space, wherein a sixth port being a different input port of the slow optical switch is prewired to a second output port of a second customer space, wherein the slow optical switch is configured to switch between connecting the fifth port to the first port and connecting the sixth port to the first port.

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