An Overview of X.25 Addressing

Addressing in a Data Network

Every user in the network, whether that user is a mainframe, terminal, printer, PAD, or other equipment, is assigned an address.

These addresses will be used to route a call from the source to the destination

in other words, from the calling party to the called party.

An address in a data network is similar to a telephone number in the telephone network; it is simply a means to reach the desired destination.

Just as telephone numbers follow a certain format, data addresses in a given network also adhere to a given format. If you tried to use a non-standard format as a telephone number, your call would either not be routed at all or would be routed to the wrong destination. The same is true in the data network.