Turing switch
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The Turing switch is a logical construction similar to the Turing machine. The Turing switch models the operation of a basic switch in a network of switches, much the same as a Turing machine models the operation of a basic computational entity. Both are named in honor of the English logician, Alan Turing. Some introductory research on the Turing switch was started at the University of Cambridge by [Jon Crowcroft].
A Turing switch consists of a switching fabric, one or more ingress interfaces (also referred to as sources), one or more egress interfaces (sinks), and a decision procedure to determine an egress interface given an ingress interface. Interfaces are sometimes referred to as ports. A packet (cell or switched unit) arrives at an ingress interface, the appropriate egress interface is determined by the decision procedure, and the packet is then transported across the switching fabric to the egress interface. A packet is a symbol or sequence of 1's and 0's. An ingress interface is connected to an ingress line, an egress interface to an egress line. The ingress line is said to feed the ingress interface; the egress interface feeds the egress line.
Throughout this entry the term Turing switch may be shortened to switch. Context will usually indicate whether we are referring to a Turing switch or a switch in general.
