Master Hub Setup and Management
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installed. If a hub stack has two master units, the master unit powered-on
first or the unit which is higher in the stack will manage the stack and be
designated the
rimary Master.” Master hubs in the series include a built-in
contention algorithm which determines which hub will manage the stack and
which will operate in standby mode. If, during power-on, the two master
hubs in the stack both attempt to initialize as the Primary Master, this colli-
sion will result in an automatic stack reset indicated by all hub ID numbers
changing to 0 temporarily. If the currently managing hub fails or is powered-
off, the standby master will take over management of the hub stack.
Segmenting Hubs
Switching hub technology has made it more common to segment local area
networks into smaller pieces to reduce congestion. Segmenting makes it
easier to balance network loads, since a smaller number compete for the
bandwidth available.
A hub stack makes network management convenient, but too many stations
on a single network segment may give slow response at peak network loads.
Therefore, this hub series provides a way to segment hubs from the stack into
their own collision domains. Segmenting hubs can be accomplished with a
simple management command and does not require any hardware or wiring
changes.
Though the hubs continue to be cascaded together and are managed as a sin-
gle unit, each hub can either be a part of the collision domain of the rest of
the stack, or can be separated into its own network segment. These separate
segments can be bridged by connecting them through a compatible switching
hub.
