Nortel Meridian 1 Description, Installation And Operation page 64

Page 64 of 262 IP Telecommuter Engineering Guidelines
553-3001-119 Standard 2.00 April 2000
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one-way delay between the time a packet is sent to the time it is
received at the remote end. It comprises of delays at the ITG node
and WAN route. To minimize delays, the ITG node should be
positioned as close as possible to the network backbone, or WAN,
with a minimum number of hops.
To assure a good voice quality, the end-to-end delay is
recommended to be <= 200 ms.
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sent that do not arrive at their destination. Transmission equipment
problems, packet delay, and network congestion cause packet loss.
It voice conversation, packet loss appears as gaps in the
conversation. Sporadic loss of small packets can be more tolerable
than infrequent loss of large packets.
For high quality voice transmission, a packet loss of <= 2% is
recommended.
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• Ping
• Traceroute
Both Ping and Traceroute are basic measuring tools for IP network. They
come with Window 95, Window NT and other packages. Pint is used to
measure round trip delay of a packet and the percentage of packet loss; while
Traceroute breaks down delay segments of a source-destination pair and any
hops in-between.
There are many vendor packages doing data collection as Ping and Traceroute
do. In addition, these programs also analyze data and plot performance charts.
To directly use Pint/Traceroute to collect data for manual analysis is tedious.
However, the information provided by these basic tools is just as useful as any
sophisticated package.
Consequently, all sequel analysis will use Ping/Traceroute data for
discussion, even though in practice, some third party packages will most
likely be used.
Packet delay is the point to point
Packet loss is the percentage of packets