Table 29 impairment factors of codecs, Table 30 impairment factors due to network delay, Table 31 impairment factors due to packet loss – Nortel Networks NN43001-563 User Manual
Page 149: Table 29 "impairment factors of codecs, Table 30 "impairment factors due to network, Table 31 "impairment factors due to
Measure intranet QoS
149
This model already takes into account some characteristics of the IP Phone,
and therefore the impairment factors are not identical to those shown in
the ITU-T standards.
Refer to
Table 32 "R value translation" (page 150)
for the translation of R
values into user satisfaction levels.
Table 29
Impairment factors of codecs
Codec
Codec Impairment (lc)
(msec frames)
G.711
0
G.729A/AB
11 - 20 or 30
G.729A/AB
16 - 40 or 50
G.723.1 (5.3 Kbps)
19
G.723.1 (6.3 Kbps)
15
Table 30
Impairment factors due to network delay
Network delay* (msec)
Delay Impairment (ld)
0 - 49
0
50 - 99
5
100 -149
10
150 - 199
15
200 - 249
20
250 - 299
25
* Network delay is the average one-way network delay plus packetization and
jitter buffer delay.
Table 31
Impairment factors due to packet loss
Packet loss (%)
Packet Lose Impairment (lp)
0
0
1
4
2
8
Nortel Communication Server 1000
IP Trunk Fundamentals
NN43001-563
01.01
Standard
Release 5.0
30 May 2007
Copyright © 2007, Nortel Networks
.