Twisted-Pair Cable/Connector Pin-Outs - HP J4897A Installation Manual

Twisted-Pair Cable/Connector Pin-Outs

The IEEE 802.3ab "Auto MDI/MDI-X" Feature: The 10/100/1000Base-T
ports on the Series 2700 Switches all have the "Auto MDI/MDI-X" feature that
is part of the IEEE 802.3ab standard. They automatically detect the type of
port on any device connected to the Series 2700 Switch and then operate as
either an MDI or MDI-X port, whichever is appropriate. If you connect a Series
2700 Switch twisted-pair port to another switch or hub, which typically have
MDI-X ports, the Series 2700 Switch port operates as an MDI port and connects
correctly. If you connect an end node, such as a server or PC which typically
have MDI ports, to the Series 2700 Switch, the switch port operates as an
MDI-X port and connects correctly.
So, for any connection, a "straight-through" twisted-pair cable can be used —
you no longer have to use "crossover" cables. If you do happen to use a
correctly wired crossover cable, though, the switch will still be able to
automatically detect the MDI/MDI-X operation of the connected device and
will link correctly.
Other Wiring Rules:
■ All twisted-pair wires used for 10 Mbps, and 100 Mbps operation must be
twisted through the entire length of the cable. The wiring sequence must
conform to EIA/TIA 568-B (not USOC). See the Pin Assignment tables
below the cable illustrations later in this appendix for a listing of the
signals used on each pin.
■ For 10 Mbps connections to the ports, you can use 100-ohm differential
Category 3, 4, or 5 unshielded (UTP) or shielded (STP) twisted-pair cable,
as supported by the IEEE 802.3 10Base-T standard.
For 100 Mbps connections to the ports, use 100-ohm differential Category
■
5 UTP or STP cable only, as supported by the IEEE 802.3u 100Base-TX
standard.
■ For 1000 Mbps connections, Category 5 or better 100-ohm differential UTP
or STP cable only, as supported by the IEEE 802.3ab 1000Base-T standard;
Category 5E or better is recommended.
Switch Ports and Network Cables
Twisted-Pair Cable/Connector Pin-Outs
B-3