Traceroute and random UDP ports

Matthew Luckie mjl at
Wed Aug 13 14:29:15 CDT 2008

These days there are better implementations of traceroute that are less
likely to infer false IP paths by not playing games with the source and
destination ports.

Paris traceroute hacks the payload of the UDP probe to use the checksum
field as the probe identifier (and also uses the IPID field as a backup
since NATs will change the checksum).  Paris traceroute also has an ICMP

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