Server User Manual

152 ITG engineering guidelines
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0.5% packet loss: lp = 8
Then:
R = 94 - 11 - 5 - 8
R=70
Using Table 33 "IP Trunk 3.01 (and later) QoS levels" (page 149), a value of
70 means some users are dissatisfied.
Does the intranet meet expected IP Trunk 3.01 (and later) QoS?
At the end of this measurement and analysis, there should be a good
indication if the corporate intranet in its present state can deliver adequate
voice and fax services. Looking at the "Expected QoS level" column in Table
28 "Sample measurement results for G.729A codec" (page 146), the QoS
level for each site pair can be gauged.
In order to offer voice and fax services over the intranet, keep the network
within a "Good" or "Excellent" QoS level at the Mean+s operating region.
Fax services should not be offered on routes that have only "Fair" or "Poor"
QoS levels.
If the expected QoS levels of some or all routes fall short of "Good", evaluate
the options and costs for upgrading the intranet. Estimate the amount of
one-way delay that must be reduced to raise the QoS level. The section
"Fine-tune network QoS" (page 132) provides guidelines for reducing
one-way delay. Often this involves a link upgrade, a topology change, or
implementation of QoS in the network.
A decision can be made to keep costs down and accept a temporary "Fair"
QoS level for a selected route. In that case, having made a calculated
trade-off in quality, carefully monitor the QoS level, reset expectations with
the end users and be receptive to user feedback.
IP Trunk 3.01 (and later) LAN installation and configuration
Basic setup of the IP Trunk 3.01 (and later) system
Figure 31 "Basic setup of the IP Trunk 3.01 (and later) system" (page
153) shows an example of a basic recommended IP Tr unk 3.01 (and
later) system setup, with separate TLAN (voice) and ELAN (management)
subnets. This is an example only; it is not necessarily the setup that must
be used.
Nortel Communication Server 1000
IP Trunk Fundamentals
NN43001-563 02.01 Standard
Release 5.5 21 December 2007
Copyright © 2007, Nortel Networks
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