[c-nsp] Setting "weight 255" as default for customer BGP with uRPF strict

[Pekka Savola]

On Sun, 21 Nov 2004, Brian Feeny wrote:
> I realize loose uRPF is the better solution, but with regards to strict uRPF, 
> does anyone see any caveats to doing this?
> (not all routers on the network are running code that support loose mode, and 
> I can only phase in a few changes at a time).

Uh oh, loose uRPF does not actually prevent the customer from spoofing 
traffic, so I wouldn't say it's "the better solution" at all..

See RFC 3704.

In rough order of preference, YMMV,
  1) Feasible Path RPF (like strict w/ weight as you're doing)
  2) Strict RPF
  3) Manual access lists
  4) Loose RPF
  5) nothing

-- 
Pekka Savola                 "You each name yourselves king, yet the
Netcore Oy                    kingdom bleeds."
Systems. Networks. Security. -- George R.R. Martin: A Clash of Kings