In the referenced message, Stephen J. Wilcox said:
On Thu, 6 Jun 2002, Stephen Griffin wrote:
In the referenced message, Sean M. Doran said:
Basically, arguing that the routing system should carry around even more information is backwards. It should carry less. If IXes need numbers at all (why???) then use RFC 1918 addresses and choose one of the approaches above to deal with questions about why 1918 addresses result in "messy traceroutes."
Fewer routes, less address consumption, tastes great, less filling.
Sean.
Do you: 1) Not believe in PMTU-D
RFC1918 does not break path-mtu, filtering it does tho..
sending RFC1918 addressed packets across enterprise boundaries is against RFC1918. RFC1918 states to filter ingress/egress at enterprise boundaries. Hence, filtering RFC1918 addresses is part of RFC1918. Therefore, the use of addresses where they are likely to generate traffic which violates RFC1918, is, well, a violation of RFC1918. This applies regardless of the ICMP error message generated.
2) Not believe in filtering RFC1918 sourced traffic at enterprise boundaries (of which an exchange would be a boundary)
What for? You'll find many more much more mailicious packets coming from legit routable address space.
Who said anything about malicious? In any event, ICMP error messages are generally useful with a few minor exceptions. Things like Source Quench, unreachables, TTL expired, and Can't Frag (as examples of useful icmp.) <snip>
For p2p you can use unnumbered.. it wont work on exchanges but i agree they shouldnt be rfc1918.
I agree, however, most folks want to see the topology, some just choose to violate RFC1918 in order to do it.
Steve