I've got an interesting little example which ideally I'd like your thoughts on....
At the moment we have a network of 10.10.10.x (255.255.255.0) giving us 253 IP addresses to use. We have now used 240 IP addresses and we need to expand the range.
Seperate the network range so that all servers/switches/printers/etc run on the 10.10.10.x (255.255.255.0) and all PC etc run on 10.10.11.x (255.255.255.0) and use the Watchguard as the G/W on both 10.10.10.x and 10.10.11.x (in affect setting two IP's on the Watchguard).
Seperate the network as shown above servers/switches/etc on 10.10.10.x and PC's etc on 10.10.11.x but use a subnet of 255.255.254.0 and the need then to only give the Watchguard a single IP.
My personal thought is option A as we dont then go over the 500 hosts per subnet but my friend thinks completely differently.