We have a network with several remote sites all connected to our main campus through a high speed metropolitan optical ethernet. We're running EIGRP and use a public class-b address space. We are strickly a layer-3 routed network in our WAN, core and distribution layer.
Now we're being asked to supply limited access for vendors who want to bring a laptop in, plug it into our network, and get internet access.
What is the best way to do that without going to a full-blown 802.1x world?
Is it through GRE tunnels on a private address space?
All ideas are welcome.