<Dt> Address formats for data exchange </Dt> <Dd> Addresses are used to identify both the sender and the intended receiver (s). The addresses are carried in the header area of the bitstrings, allowing the receivers to determine whether the bitstrings are of interest and should be processed or should be ignored . A connection between a sender and a receiver can be identified using an address pair (sender address, receiver address). Usually some address values have special meanings . An all - 1s address could be taken to mean an addressing of all stations on the network, so sending to this address would result in a broadcast on the local network . The rules describing the meanings of the address value are collectively called an addressing scheme . </Dd> <Dd> Sometimes protocols need to map addresses of one scheme on addresses of another scheme . For instance to translate a logical IP address specified by the application to an Ethernet MAC address . This is referred to as address mapping . </Dd> <Dd> When systems are not directly connected, intermediary systems along the route to the intended receiver (s) need to forward messages on behalf of the sender . On the Internet, the networks are connected using routers . The interconnection of networks through routers is called internetworking . </Dd>

Protocol is a set of rules that controls how data is sent between computers