
switching transition, unless there is enough time gap between the packets to accom-
modate the switching transition. This gap, called “guard time,” must be longer than the
switching time of the slowest packet switch in the path, and must provide room for any
additional uncertainty in timing. Hence, efficient OPS networking requires fast switch-
ing and accurate timing in all OPS systems in the network.
In addition, OPS systems should be scalable to support many wavelengths and
ports. For instance, the number of swit ching elements (control points) increases as
N
2
in an N N crosspoint switch, where N is a product of the number of ports K
and the number ...