| To expand the scenario for clarification (Not to say that I don't think I'm wrong, I often am :D that's why I check) I have a host machine at 111.111.50.50 /24. The user sitting there wants to go to this fine web site right here. It connects via a station cable to a L2 switch 111.111.50.2/24 (I know...IP is irrelevant at this point, it's all MAC). That switch, via Gig1 attaches to a L3 switch with multiple interfaces. So let's say that distribution switch has 111.111.50.1/24 in it, which also happens to be OSPF area 5. The router ID on said switch is 223.255.255.46. It also has /30 addresses in the 10.x.x.x network connecting it to other layer 3 switches. Everything is GigE. There is an interface in area 0 that connects to the core at 10.10.5.2/32. The core is 10.10.5.1/30, as well as 10.10.1.1, .2.1, .3.1, etc. For each of the distribution switches. The core is also 111.111.1.2 and (router ID) 223.255.255.254. The edge router is 111.111.1.1/30 and does not have OSPF running on it. The core switch has a static default route set of 0.0.0.0 0.0.0.0 111.111.1.1 So that little packet from 111.111.50.50 destined for 66.96.26.214 crosses from the switch to the edge router, what is it telling it that the return path is? 111.111.1.2 (the connected interface) or 223.255.255.254 (the router ID)? That's where I'm apparently confused. | 
