Brocade Communications Systems, Inc.

Lino Costantino

Howard Green

Brian Forbes

A system and method are disclosed for combining physically separate subnets of an Infiniband (IB) network into virtual subnets. In the virtual subnets, all of the end node in one subnet may be allowed to access all of the end nodes in another subnet, or the access may be limited to only a selected subset of another subnet. In addition to processing of globally-routed IB packets, the router also communicates (alone or in cooperation with another router) locally-routed IB packets traveling between a designated end nodes in different subnets. The routers may encapsulate the packets into raw datagrams for transport across intervening subnets. The described system and method may advantageously allow remote end nodes to act as a part of a given subnet, and may advantageously allow routers to provide both switch and routing functionality.

Combining separate infiniband subnets into virtual subnets

An Infiniband (IB) router with an internal subnet architecture is disclosed. It comprises multiple port interface circuits interconnected by an internal IB subnet. The multiple port interface circuits each connect to an external IB subnet and preferably determine new local route headers (LRH) for global IB packets (i.e. packets having a global route header (GRH)). The new LRHs for externally received packets include a destination local identifier (DLID) value that identifies another port interface circuit in the router, whereas the new LRHs for internally received packets include a DLID value that identifies an end node or router in the external subnet to which the port interface circuit is attached. The internal IB subnet transports IB packets between the port interface circuits, directing them according to the contents of the LRHs. The internal subnet may take the form of an IB switch or a network of IB switches.

Infiniband router having an internal subnet architecture

A multiport switch assembly comprises a plurality of discrete switch devices coupled together in a way that virtualizes the behavior of a multiport switch assembly. Each of said switch devices preferably has fewer ports than the number of ports made externally available by the multiport switch assembly. The multiport switch assembly preferably comprises a plurality of tiers of switch devices and a processor connected directly or indirectly to all or at least some of the switch devices. The processor executes code that permits the multiport switch assembly to appear, from the viewpoint of external logic (e.g., management entities, end nodes, routers, etc.), to operate as a single switch device. This alleviates the burden on the external logic, which otherwise would have to control each individual switch device to accomplish the desired switching behavior of the switch assembly.

Virtualized multiport switch

A router is disclosed for supporting local-level communication between separate subnets managed by different subnet managers. The router preferably makes one or more end nodes from one subnet 'visible' to the subnet manager of another subnet. The end nodes may consequently be identified by one local identifier (LID) value in one subnet, but by another LID value in a different subnet. In a preferred embodiment, the router accepts from a first subnet local IB packets directed to end nodes made visible from a second subnet, and processes the local IB packet to convert the first subnet LID values for destination and source end nodes to second subnet LID values for these end nodes.

Growing community of inventors

Oakland, CA, United States of America

Lino Costantino