.\" @(#)CG56switch4x4	1.1 12/17/92
.NA "Switch4x4"
.SD
A four-input, four-output network switch.
.SE
.LO "~ptolemy/src/domains/de/demo"
.SV 1.1 11/8/92
.AL "Paul Haskell."
.LD
This galaxy implements a network switch that can process
objects of type
.c NetworkCell
or any type derived from NetworkCell.
Each NetworkCell object contains a destination address.
This galaxy uses the destination address as an index into its
.c Routes
array state to choose an output port over which the input object
will leave.

Each output port is served by a
.c virtual clock
queue and server.
If the queue begins to fill, arriving NetworkCell objects
of low priority get discarded.

See
H. Zhang and S. Keshav,
"Comparison of Rate-Based Service Disciplines,"
\fIACM SIGCOMM'91 Conference\fR,
vol. 21, #4, September 1991, pp. 113-121.
for a discussion of the virtual clock and other buffer service
disciplines.
.ES
