Consider packet for another university addressed to 10.10.1.20. First, routers outside this campus would match the packet's address against 10.10/16 and directed it towards the university. Having reached a campus router, the address would then be matched against 10.10.1/24 and be forwarded towards Einstein Hall. Having reached a router within the building, a match against 10.10.1.0/27 would point to routers attached to Newton Lab. Finally, a router directly connected to the Newton Lab Ethernet would determine 10.10.1.20's Ethernet address and deliver the packet to its final destination.