19.4 PACKET SWITCHING NODE AND MESSAGE
STRUCTURE
The building block of any scalable photonic switching network is the switching
node, the crosspoint where optical pathways intersect and allow optical packets to
traverse the network from one of multiple input terminals to one of multiple
outputs. OIN topological specifications, along with the aforementioned delegation
of capacity and functionality, yield design considerations for the switching node
and message format.
The motivation for implementing an optical packet switching fabric from
simple switching node building blocks is twofold: (1) optical components are
still expensive and not easily integratable, and (2) architectures composed of
simple switches with a distributed control scheme scale straightf ...