private ip addresses from ISP

Joe Maimon jmaimon at
Tue May 23 15:14:53 UTC 2006

Robert Bonomi wrote:

> TTL-E messages _do_ have legitimate function in network management.
> TTL-E messages _can_ originate from RFC1918 space,  addressed to 'public
> internet' addresses.  Usefully, and meaningfully.  Ever hear of 'traceroute'?
> Ever use it where packets went across a network using RFC1918 internally?
> Ever had a route die _between_ two RFC1918 addressed nodes on somebody elses
> network?

I guess this means that providers who utilize rfc1918 along their hops 
should make an effort to ensure these addresses are not used for icmp 
messages or translate these addresses when they source icmp.

Understandably, translation on providers networks is not always feasible.

A feature on routers that sourced icmp packets to be told specificaly 
which address of the router to source it from would also help.

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