Consider your company’s needs when planning your Internet connection. If all you need is one-way connectivity to enable internal users to connect to sites on the Internet, a private IP address space with Network Address Translation (NAT) should suffice. If external users need to connect to resources, such as servers, inside your network, you need some public IP addresses. You might combine these with private addresses and NAT for your users.
If external users must connect to your internal resources, you should plan the following:
• How many public IP addresses will you need?
• Should you get your IP addresses from your ISP or acquire your own? If ...