A network device selects at least one other network device as its backup
and communicates information for use by the backup network device(s) in
assuming the role of the network device upon its unavailability. The
network device also receives information from at least one network device
that has selected it as its backup device for use in assuming the role of
the selecting device(s) upon unavailability of the selecting device(s).
Each network device may act as a backup for the same number of devices as
it has backups. Selection of backup devices may be based on device
reliability. In one embodiment, each network device has a primary and
secondary backup. The primary backup assumes the role of the network
device when the latter becomes unavailable, and the secondary backup
assumes the role of the network device when both the network device and
its primary backup are unavailable.