At my home I have a standard network...cable modem ->broadband router -> to 4 pcs.
Until recently we had 4 big box pcs that stayed where they where...but swmbo and I are moving to laptops...and the big boxes being relegated to more important mach3 duties.
My ISP only allows me one IP address (fairly standard)..so cable modem -> WAN -broadband Router- ->LAN to PCs.
The cable modem will communicate with only one MAC address, and will issue only one IP address via DHCP...the router is the single device to which the cable modem issues the single IP address, and the other PCs communicate with the internet via a process of Network Address Translation (NAT) performed by the router.
If I have had my laptop network connected and working to the router LAN port RJ45 in the front room and unplug it..replacing it with swmbo work laptop
I will get the "connection not available" messages as expected..(and if I reconnect mine it works fine again)
I have tried to use the XPs ipconfig /release and ipconfig /renew (and gui-Network Connections->repair) to get the routers internal DHCP server to release the old settings and allow the newly connected laptop to work with no joy.
Power cycling the router does allow the Laptops to be swapped.
How can I swap the laptops without power cycling the router?..
Can't use wireless due to existing noise and the amount on networks already in the area..Its the reason I went back to cable.(and safer with the new laws affecting the UK).
Micro$oft or other ICSs are not an option.
edits in red