A Wavefront arbiter is a circuit used to make decisions which control the crossbar of a high capacity switch fabric in parallel.
[1] It was commercialized in the TT1 and TTx chip sets designed by Abrizio and sold by PMC-Sierra.
A set of decisions of which inputs are connected to which outputs must be made each arbitration period.
An arbiter is the circuit that makes the decision as to which of the crossbar's many switches should be closed.
Speed is a key design criterion of an arbiter in some applications.