THOMSON SpeedTouch 620, Руководство оператора

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Chapter 12
SLA Monitoring.
E-DOC-CTC-20051017-0155 v1.0
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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
=>