A switch core is set forth that comprises a plurality of duplex switches that
are
interconnected with a interconnection fabric to implement, for example, strictly
non-blocking operation of the switch core for reciprocal traffic. In one embodiment,
an N-way reciprocal switch is implemented. The N-way reciprocal switch comprises
a plurality of duplex switches numbering N of at least a 1(N-1) switch type
(e.g., the duplex switches have at least N-1 ports available for connection to
implement the interconnection fabric). The interconnection fabric interconnects
the plurality of duplex switches so that each duplex switch is connected to every
other duplex switch used in the interconnection fabric by a single connection.
A similar architecture using switches numbering N of at least a 1N switch
type are also set forth. Still further, a plurality of duplex switches are used
to implement an (n,m)-way switch that, in turn can be used to construct a recursive
LM-way switch core and/or recursively expand an existing Clos switch core.