An Overview of OSI Conformance Testing

The development of distributed systems, in which the computer functionality, such as processing functions, information storage, and human interaction, is distributed over different computer systems, raises the need for exchanging information between these systems. To have computer systems communicate successfully, the communication must occur according to well-defined rules. A protocol describes the rules with which computer systems have to comply in their communication with other computer systems. A protocol entity is that part of a computer system that takes care of the local responsibilities in communicating according to the protocol.