Nortel Ethernet Routing Switch 8000 Series Installing And Maintaining page 77

alike, they both attempt to send data out on the same RJ-45 pins. In such a
case, a straight-through cable does not work. However, a crossover cable
operates normally.
The 8648TXE, 8648TXM, and 8632TXE modules are designed to have
Ethernet network interface cards (NICs) connect directly to their RJ-45 ports
using straight-through cables. NIC's port types are MDI. However, if an
8648TXE, 8648TXM, or 8632TXE module must connect to a hub or another
switch that follows usual conventions, a crossover cable is required because
the port types are MDI-X. You only need crossover cables when connecting
cables to devices that have the same port type.
100BASE-T and 1000BASE-T cables
The 100 Mbit/s ports and 1 Gbit/s ports are designed to operate using
Category 5 UTP cabling only. Category 5 UTP cable is a two-pair cable. To
minimize crosstalk noise, maintain the twist ratio of the cable up to the point
of termination; untwist at any termination cannot exceed 0.5 in. (1.27 cm).
GBIC cables
Cables for the GBICs vary depending on the specific GBIC type. For
information about the cable requirements for GBICs, see Installing SFP and
XFP Transceivers and GBICs (NN46205-305; 318034-D).
Installing and Maintaining the Ethernet Routing Switch 8000 Series Chassis
Copyright © 2007, Nortel Networks
.
Nortel Ethernet Routing Switch 8600
NN46205-303 01.01 Standard
4.1 2 January 2007
Troubleshooting 77
Nortel Networks Confidential