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Traceroute Program

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Introduction - Problem

Wich route do my packets follow towards my destination?

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Traceroute used packets

Traceroute program uses :

UDP packet destination port > 30000

small TTL

ICMP time exceeded

ICMP port unreachable error

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Traceroute 131.107.7.29

IP Address = 131.108.7.29

ICMP Port Unreachable

traceroute 131.107.7.29traceroute 131.107.7.29

UDP, port 33123, TTL=3UDP, port 33123, TTL=2UDP, port 33123, TTL=1

TTL=0TTL=0TTL=0TTL=0

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Command

Usage: tracert [-d] [-h maximum_hops] [-j host-list] [-w timeout] target_name

Options:

-d Do not resolve addresses to hostnames.

-h maximum_hops Maximum number of hops to search for target.

-j host-list Loose source route along host-list.

-w timeout Wait timeout milliseconds for each reply.

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Exercise: Find out about the Traceroute options