3Com MSH 1005, User Manual

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DUA1840-0AAA01
Configuration Rules for Fast Ethernet 1 - 15
Configuration Rules for Fast Ethernet
The topology rules for Fast Ethernet (100Mbps) are slightly different to
those for 10Mbps Ethernet. The key topology rules are:
■
Maximum UTP cable length is 100m (328ft) over category 5 cable.
■
A 412m (1352ft) fiber run is allowed for connecting switch to switch, or
end-station to switch, using standards-compliant half-duplex
100BASE-FX.
■
A total network span of 325m (1066ft) is allowed in single-repeater
topologies (one hub stack per wiring closet with a fiber run to the
collapsed backbone); for example, a 225m (738ft) fiber downlink from a
repeater to a router or switch, plus 100m (328ft) UTP run from a
repeater out to the desktops.
Configuration Rules with Full Duplex
The MSH Switch 1005 provides full duplex support for any Fast Ethernet
Transceiver Modules that are installed. Full duplex allows frames to be
transmitted and received simultaneously and, in effect, doubles the
bandwidth available on a link.
With full duplex, the topology rules are:
■
Maximum UTP cable length is still 100m (328ft) over category 5 cable.
■
A 2km (6562ft) fiber run is allowed for connecting switch to switch, or
end-station to switch.