User’s Manual 576.2.1 IP Addresses ExplainedIP (Internet Protocol) addresses are expressed as 4 decimal numbers separated by periods,for example:216.103.126.15510.1.1.6Each decimal number must be between 0 and 255. The total IP address is a 32-bit numberconsisting of the 4 bytes expressed as shown above. A local network uses a group of adja-cent IP addresses. There are always 2N IP addresses in a local network. The netmask (alsocalled subnet mask) determines how many IP addresses belong to the local network. Thenetmask is also a 32-bit address expressed in the same form as the IP address. An examplenetmask is:255.255.255.0This netmask has 8 zero bits in the least significant portion, and this means that 28addresses are a part of the local network. Applied to the IP address above(216.103.126.155), this netmask would indicate that the following IP addresses belong tothe local network:216.103.126.0216.103.126.1216.103.126.2etc.216.103.126.254216.103.126.255The lowest and highest address are reserved for special purposes. The lowest address(216.102.126.0) is used to identify the local network. The highest address(216.102.126.255) is used as a broadcast address. Usually one other address is used for theaddress of the gateway out of the network. This leaves 256 - 3 = 253 available IPaddresses for the example given.
