On Fri, 14 Jun 2013 13:21:09 -0400, Scott Helms said:
How? There is truly not that much room in the IP packet to play games and if you're modifying all your traffic this would again be pretty easy to spot. Again, the easiest/cheapest method is that there is a backdoor there already.
Do you actually examine your traffic and drop packets that have non-zeros in reserved fields? (Remember what that did to the deployment of ECN?) And there's plenty of room if you stick a TCP or IP option header in there. Do you actually check for those too? How fast can you send data to a cooperating router down the way if you splat the low 3 bits of TCP timestamps on a connection routed towards the cooperating router? (SUre, you just busted somebody's RTT calculation, but it will just decide it's a high-jitter path and deal with it).