> Two or more access points to roam on. How do the APs themselves interconnect
> and eventually to the router? By cables or by wireless?
The APs don't interconnect. If they have the same ESSID and your client
equipment is set to find the strongest signal, the client homes in on
the best AP. How the APs are connected isn't really relevant.
Not true at all. Access points do interconnect for roaming however the
interworking protocol isn't standardised across vendors.
This has to happen for example if AP A has packets that are queued for a
NIC which is in power save mode and the machine moves to the area
covered by AP B.
Typically they will be connected via cable.
This presentation gives a few other things to think about too
http://www.usg.edu/conferences/networking/wlan.pdf
David.