Data communications services networks x
Basic aspects of the X.25 network:
The protocol specifies:
X.25 is one of the oldest and still available packet-switched services that were made available in public in most countries during the 1970s and 1980s to lower down the cost of accessing different online services. Examples of X.25 networks that were made publicly available are Tymnet, Compuserve, Datanet 1, PSS, Euronet, Telenet, and Datapac. It is an ITU-T standard protocol suite that is used as packet switch in a Wide Area Network communication [WAN] or simply an X.25 WAN.
It is composed of nodes of packet-switching exchange or PSE that acts as the networking hardware, and plain old telephone service connections, ISDN connections, and or rented lines that acts as the physical links. It is a group of protocols used by telecommunications companies and also used in financial transaction systems like ATMs or Automated Teller Machines that was popular in the 1980s. After the great advancement in technology, the X.25 is being replaced to a great degree by less complicated protocols such as Internet Protocol or IP.
Here is how to describe an X.25 Network: