Nortel Networks NN43001-504 - Manual (Page 80)

80 System information
2245 repackages the voice data to the correct packet size. The jitter buffer
is always configured to 70 ms, and any UNIStim messages that configure
the jitter buffer are ignored.
ATTENTION
IMPORTANT!
If the wireless handset is registered to the same LTPS as the IP Phones, configure
only the subset of codecs supported by both the wireless handsets and the IP
Phones.
If it is necessary for the IP Phone to use a codec that is not supported on
the wireless handsets, such as G.723.1, the wireless handsets must be
configured on their own separate node.
If a remote endpoint is configured for G.723.1 as the Best Bandwidth
(BB) Codec and G.711 as the Best Quality (BQ) Codec, (G.729 is not
configured), the media path negotiates to G.711. The result can be
unexpected consequences on a narrow-band link.
Jitter buffer
The handsets do not support a configurable jitter buffer. If they receive the
Jitter Buffer Configuration UNIStim message, the command is ignored. The
jitter buffer is fixed at 70 ms.
There are two implications of a fixed jitter buffer setting:
• If the system jitter buffer setting is less than 70 ms (default is 50 ms),
there is a slightly longer delay in the IP Phone receive direction.
• If the system jitter buffer setting is longer than 70 ms to accommodate
severe network jitter, there could be slightly higher packet loss in the
IP Phone receive direction.
The longer than normal jitter buffer setting is reasonable since extra jitter is
introduced by the RF portion of the link.
RLR and SLR
The handsets do not support UNIStim messages used to adjust the Receive
Loudness Rating (RLR) and Send Loudness Rating (SLR) of the wireless
handset.
RTCP
Handsets do not support Real-time Transport Control Protocol (RTCP).
Incoming RTCP packets sent to the wireless handsets are actually sent to
the WLAN IP Telephony Manager 2245 and are discarded. If the wireless
handset is queried for RTCP parameters, the wireless handset returns
dummy values of 0 jitter, 0 latency, and 0 packet loss.
Nortel Communication Server 1000
WLAN IP Telephony Installation and Commissioning
NN43001-504 01.02 Standard
Release 5.0 15 June 2007
Copyright © 2004-2007, Nortel Networks
.