Resilience
4-33
Resilience
You can make your network more robust by adding
resilience
to it.
When a link fails, as shown in
Figure4-14
, all
communication between equipme nt on each side of
the link is lost. It would be very inconvenient for a
manager to physically reinstate the network
immediately and important communication might
be lost.
Figure4-14
A
Failed Link Between Two Hubs
If a spare link could automatically pick up when the
broken link failed, the network would appear to
function normally to the user. At worst, a few packets
would be corrupted or lost.
This is the concept of resilience. One link is on
standby (called the
standby
link) waiting to take over
if another link (called the
main
link) fails, as shown in
Figure4-15
. This pair is called a
resilient link pair
.
Figure4-15
A
Resilient Link Pair

16710.bk : MANAGING.FRM Page 33 Tuesday, October 7, 1997 11:38 AM