Nortel Meridian 1 Description, Installation And Operation page 67

Delay characteristics vary depending on the site pair and the time-of-day.
A "site pair" is defined as the measurement between the host ITG and the
remote subnet served by a remote access server or router (for example, ITG
to subnet A in Figure 18). The assessment of the intranet should include
taking delay measurements for each ITG site pair. If there are significant
fluctuations of traffic in the intranet, it is best to include ping samples during
the intranet's peak hour. For a more complete assessment of the intranet's
delay characteristics, obtain ping measurements over a period of at least a
week.
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The ping program also reports whether the ICMP packet made its round trip
successfully or not. In fact, use the same ping host setup to measure
end-to-end error, and, as in making delay measurement, use the same packet
size parameter.
Sampling error rate, however, requires taking multiple ping samples (at
least 30 to be statistically significant), thus obtaining an error distribution
requires running ping over a greater period of time. The error rate statistic
collected by multiple ping samples is called packet loss rate (PLR).
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Routing information for all source-destination pairs needs to be recorded as
part of the network assessment. This is done using the traceroute tool; an
example of the output is shown below.
itg_node1 % traceroute subnetA
traceroute to subnetA 10.3.2.7, 30 hops max, 32 byte
packets
1 r6 (10.8.0.1) 1 ms
2 r5 (10.18.0.2) 42 ms
3 r4 (10.28.0.3) 78 ms
4 r1 (10.3.0.1) 92 ms
5 subnetA (10.3.2.7) 94 ms
ITG Line 1.0/IP Telecommuter Description, Installation and Operation
IP Telecommuter Engineering Guidelines
1 ms 1 ms
44 ms 38 ms
70 ms 81 ms
90 ms 101 ms
97 ms 95 ms
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