My ISP charges an extra $5/mo for an extra IP. I will have 2 computers connected to the internet; do I have to get the extra one, and what advantages does having a different IP for each computer have? Thanks.
You don't need 2 IP's... You can have 2 (or more) computers behind a router with NAT and just set port forwarding for file sharing / servers etc and save yourself $5/month ($60/year). If you have 2 IP addresses and 2 Computers each can have there own address, so you wouldn't need NAT or to set port forwarding.... but it means your computers are alot more exposed (to the internet) as all of the computers ports are accessible! I would go with a single IP and get a router (port forwarding can be a pain, but its a small price for a extra layer of protection).
