In Switches, switch inputs and outputs may be grouped into (e.g., small) modules
called input shared blocks (or "ISBs") and output shared blocks (or "OSBs"), respectively.
Each of the switches includes three (3) main parts: (i) input shared blocks (ISBs);
(ii) a central switch fabric (or "ATMCSF"); and (iii) output shared blocks (OSBs).
Input link sharing at every ISB-ATMCSF interface and output link sharing at every
ATMCSF-OSB interface cooperate intelligently to resolve output contention and essentially
eliminate any speedup requirement in central switch fabric. Each of the proposed
switches can easily scale to a large size by cascading additional input and output
shared blocks (ISBs and OSBs). Instead of using a centralized scheduler to resolve
input and output contention, the each of the switches applies a distributed link
reservation scheme upon which cell scheduling is based. In one embodiment, a dual
round robin dynamic link reservation technique, in which an input shared block
(ISB) only needs its local available information to arbitrate potential modification
for its own link reservation, may be used.