RE: Where is the edge of the Internet? Re: no ip forged-source-address

One of my clients is currently a victim of an over-zealous ISP
recklessly trying to implement rpf.

One (of two) ISPs are trying to monitor my customer's circuit by
watching the serial interface (IP address) of the cpe (customer owned
and controlled) router (IP address is from ISP's block). Due to the
fact that this customer has a T1 to one ISP and a DS-3 to another ISP,
the return path of this monitoring traffic is sent via the 2nd ISP's
link. This 2nd ISP (DS-3) is dropping the packets because they are
being sourced from the serial interface (IP address of 1st ISP).

Advertised routes != valid source addresses.... is this not obvious? I
can think of MANY examples of different sets of prefixes being
advertised across different links, while the routing decision for
outbound packets does not consider what routes are being advertised.