A set of rules for sending information over a network. Protocols can include rules concerning any or all of the following functions:
Protocols are usually classified according to the layer they correspond to in the Open Systems Interconnection (OSI) reference model for networking. Types of protocols include the following:
Some protocols have been developed by specific vendors and then accepted as de facto standards by the industry, while others were initially formulated by independent standards bodies and then accepted and implemented by vendors. The most widely implemented protocols are those relating to TCP/IP and the Internet.