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Traceroute process, Sla traceroute configuration, Chapter 12 – Technicolor - Thomson Wireless Business DSL Routers SpeedTouchTM620 User Manual

Page 207

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Chapter 12

SLA Monitoring.

E-DOC-CTC-20051017-0155 v1.0

197

Traceroute Process

Traceroute is usually implemented by transmitting a series of probe packets with
increasing time-to-live values. A probe packet is a UDP datagram encapsulated into
an IP packet. Each hop in a path to the target (destination) host rejects the probe
packet (probe's TTL too small) until its time-to-live value becomes large enough for
the probe to be forwarded. Each hop in a traceroute path returns an ICMP message
that is used to discover the hop and to calculate a round trip time. Some systems
use ICMP probes (ICMP Echo request packets) instead of UDP ones to implement
traceroute. In both cases traceroute relies on the probes being rejected via an ICMP
message to discover the hops taken along a path to the final destination. Both
probe types, UDP and ICMP, are encapsulated into an IP packet and thus have a TTL
field that can be used to cause a path rejection.

SLA Traceroute

configuration

The SLA trace route process can be configured by executing the following CLI
command:

The following parameters are mandatory :

test

: this is just a name to identify the trace route test.

addr

: this is the peer IP address of which we want to trace the route.

=>:sla traceroute add test=route addr=11.0.0.138

=>