Nortel Networks NN43001-563 - Manual (Page 161)

IP Trunk 3.01 (and later) LAN installation and configuration 161
WARNING
Configure the ports on Layer 2 or Layer 3 switching equipment
as auto-negotiate.
If one side is manually configured, and the other side is configured
as auto-negotiate, the following situation occurs.
The auto-negotiate side sets itself to the manually configured
side’s speed, but always sets itself to half-duplex transmission. If
the manually-configured side is full-duplex transmission, then a
mismatch occurs and voice quality is unsatisfactory.
Recommendation
Nortel recommends that any network equipment connected to the ELAN or
TLAN subnet be configured as auto-negotiate for correct operation.
I/O filter connector
The other major TLAN subnet operation problem arises from the standard
I/O filter connector in IPE modules on Large Systems.
Use the following guidelines to avoid system interruption stemming from the
standard I/O filter connector in IPE modules:
• Ensure that the standard IPE module I/O filter is replaced with the
provided Media Card/ITG-specific filter connector that removes filtering
from pairs 23 and 24.
• Do not install the Media Card/ITG-specific filter connector on top of the
standard IPE module I/O filter connector.
• Replace the IPE module backplane I/O ribbon cable assemblies with
those that have interchangeable I/O filter connectors.
• The TLAN UTP cabling must meet the UTP CAT5 termination and
impedance uniformity standards.
• The TLAN UTP cabling must not exceed 50 meters for the ITG-Pentium
24-port trunk card.
The TLAN network interface can auto-negotiate to 100BaseT full-duplex. To
ensure the TLAN subnet can be used for voice, do the following:
• Install the Media Card/ITG-specific filter connector correctly by replacing
the standard IPE Module I/O filter connector.
• Order new IPE Module Backplane I/O ribbon cable assemblies that have
interchangeable I/O filter connectors if it becomes necessary to use one
of the IPE Modules with molded-on I/O filter connectors.
• Ensure that the TLAN UTP cabling is CAT5 compliant.
• Always keep the TLAN UTP cabling to less than 50 meters for the
ITG-Pentium 24-port trunk card.
Nortel Communication Server 1000
IP Trunk Fundamentals
NN43001-563 01.01 Standard
Release 5.0 30 May 2007
Copyright © 2007, Nortel Networks
.