[e2e] determining ingress interface?

[Rajesh Talpade]

Hi

I asked this question on the NANOG mailing list.....

> Is there a way for an ISP to determine the ingress router interface at
> its network border that _should be_ passing IP traffic _from_ an IP 
> address not owned by it? In other words, given an IP address, I would 
> like to know what interface should be used by traffic from this address 
> to enter my network.
> I realize the interface used may change over time.

....and got some answers....


> Use "traceroute -g" (Randy Bush, Buddy Bagga)
  Issues: Not all ISPs allow it; is only useful for a few hops into peer 
  ISP networks, and for IP addresses belonging to peer ISPs

> Use traffic filters/logs on routers (Dylan Greene)
  Issues: Requires instantiation on all border routers; requires traffic 
  from IP address to exist

> Use routes learned from peer ISP (Dylan Greene)
  Issues: Requires assumption that paths are same in both directions


Is there work that answers the question without requiring the traffic to
exist or assuming same bi-directional paths, perhaps using BGP path info, 
or data from CAIDA's skitter tool?

Thanks!
Rajesh.