A method and apparatus for line card redundancy in a communication switch
is presented. The switch includes an arbiter coupled to the input of a
switch core and a line card pair. The first line card of the line card
pair is considered an active line card, whereas the second line card of
the line card pair is considered the redundant, or inactive, line card.
The active and inactive line cards are determined based on selection
information received by the arbiter. Based on the selection information,
the arbiter preferentially provides ingress data from the active line
card to the corresponding input of the switch core. A router is coupled
to the line card pair and to an output of the switch core. The router
passes egress data from the switch core to at least one of the first and
second line cards based on routing information included in the egress
data.