Patent ID: 8743890

Claim:
A system for supporting multiple domains in an InfiniBand (IB) fabric, comprising: an inter-domain discovery and routing engine (ISDR) that is responsible for establishing a global fabric view and establishing a deadlock free routing with one or more paths between different end-ports in the IB fabric wherein the ISDR operates in either a fixed-route mode or an on-demand-route mode, and wherein, in the fixed-route mode, the ISDR analyzes the topology, and determines if a suitable routing engine exists, and in the on-demand-route mode, the ISDR does not establish a routing until a request for a path between two end points is received; one or more subnets, wherein each said subnet contains one or more switch nodes, wherein at least one said subnet is adapted to be divided into one or more sub-subnets, wherein each said sub-subnet is managed by a separate sub-subnet manager that is associated with a unique management key, and wherein said one or more sub-subnets are connected by one or more sub-subnet gateway switch nodes, wherein each sub-subnet gateway switch node belongs to one sub-subnet.