10/100 Fast Ethernet Switch User’s Guide
Overview
3
100BASE-TX Technology Overview
Cables and Connectors
Category 5 unshielded twisted-pair (UTP) cables are supported.
UTP Category 5 cable uses the same RJ-45 connector used with
10BASE-T, wired in the same configuration. Please note that the
punch-down blocks in the wiring closet must also be Category 5
certified. Where these blocks do not meet the standard, an
upgrade is necessary.
Topology
A Fast Ethernet workgroup is configured in a star topology and is
built around a maximum of two repeaters. Each workgroup forms
a separate LAN (also known as a segment or collision domain),
and these workgroups can be easily interconnected through
switches, bridges, or routers to form one LAN large enough to
encompass a high-rise building or campus environment. Recent
innovations in LAN hub technology such as stackable hubs,
coupled with the decreasing cost of switches, bridges, and routers,
allow the design of low-cost, efficient Fast Ethernet workgroups
and enterprise LANs.
The following factors strongly influence the architecture of Fast
Ethernet networks:
•
The EIA/TIA 568 Wiring Standard imposes a 100 meter
limit on horizontal runs of twisted-pair cables; that is,
connections from the wiring closet to the end-station.
•
Fast Ethernet’s increased operational speed reduces the
maximum distance between all elements of the LAN (see
below).
