Abstract: A bus interface for transfer of SONET/SDH data that supports a plurality of SONET/SDH flows. The invention supports two line coding schemes: 8B/10B encoding of STS-12, and SONET scrambled coding for STS-12, STS-48, and STS-51. The invention additionally supports two modes of line testing: entire links can be tested by inserting and checking PRBS sequences, and the SPE payload of the largest concatenated STS-Nc which the link can carry (STS-12c, STS-48c, STS-51c) can be individually tested by inserting and checking PRBS sequences.

Abstract: Generally speaking, the cell switching architecture of the present invention offers a powerful, simple, and in many ways elegant solution to the problem of providing cost-effective, high-bandwidth, fault-tolerant cell switching. The architecture is based on a network of switching elements connected in a hypercube topology to form a switch fabric. The generalized hypercube is D dimensional, where D≧3 when all radices in the radix set are 2 and D≧2 when at least one of the radices is greater than 2. A fully-populated switch is fully symmetric: each switching element has the same number and kind of connections to both its neighbors and to the outside world as every other switching element. In an exemplary embodiment, each switching element is connected to one data source and one data sink, e.g., a Utopia bus or other broadband connection. In the same exemplary embodiment, links between switching elements are bidirectional and synchronous, operating in accordance with a Cell Exchange Cycle (CEC).