Mastering™ Network Security, Second Edition

3.3. The OSI Model

In 1977, the International Organization for Standardization (ISO) developed the Open Systems Interconnect Reference Model (OSI model) to help improve communications between different vendors' systems. The ISO was a committee representing many organizations, whose goal was not to favor a specific method of communication but to develop a set of guidelines that would allow vendors to ensure that their products would interoperate.

The ISO was setting out to simplify communications between systems. Many events must take place in order to ensure that data first reaches the correct system and is then passed along to the correct application in a useable format. A set of rules was required to break down the communication process into ...