Patent ID: 7263097

Claim:
A Programmably-Sliceable Switch-fabric Unit (PSSU) having a capability of functioning as an N×N′ crossbar, and also having a capability of being programmably sliced to instead function as a plurality of S×S′ virtual switch slices, where S<N and S′<N′, wherein N does not have to equal N′, and S does not have to equal S′, said PSSU comprising: (a) absolute Ingress ports (aI's) and absolute Egress ports (aE's) that are alternatively identifiable as Relative ingress ports (Ri's) and Relative egress ports (Re's) of respective ones of said virtual switch slices; where the aI's can receive routing requests and payloads that are to be routed, and where the aE's can output routed payloads to corresponding destinations; and (b) a request translator, operatively coupled to the aI's for receiving routing requests from the aI's, said request translator having: (b.1) first means for determining, based on the absolute Ingress port identification (aI x ) of an ingress port on which a given request arrived, what virtual switch slice a corresponding payload signal belongs to; (b.2) second means for determining from a Relative egress port identification (Re) or ports identifications (Re's) specified directly or indirectly in the given request, and from the identification of the virtual switch slice provided by said first means, which absolute Egress port (aE) or absolute Egress ports (aE's) the corresponding payload signal is to egress from in accordance with the given request; and (b.3) third means for altering the given request before the request is submitted to a scheduler so that the altered request asks for egress of the corresponding payload signal from said determined aE or aE's.