Protocol Standards Defined by IEEE Project 802 and FDDI

This article was previously published under Q103954

IEEE Standard 802 for Local Area Networks

Recognizing a need for standards in the LAN market, the Instituteof Electrical and Electronics Engineering (IEEE) undertook Project802. Named for the year and month ('80 Feb) of its inception,Project 802 defined a family of low-level protocol standards atphysical and data link layers of the OSI model.

In IEEE 802 terms, the OSI data link layer is divided into twosublayers: logical link control (LLC) and media access control(MAC).

The data link layer functions allocated to the LLC sublayer are:

  • Link establishment and termination
  • Frame traffic control
  • Frame sequencing
  • Frame acknowledgment
The data link layer functions allocated to the MAC sublayer are:

  • Frame delimiting
  • Frame error checking
  • Media access management
The low-level protocol standards defined by IEEE project 802include 802.3 CSMA/CD, 802.4 token bus, and 802.5 token ring.These standards differ at the physical layer and media accesscontrol sublayer, but are compatible at the logical linkcontrol sublayer.

The 802 standards have been adopted by:

  • ANSI as American national standards
  • NBS as government standards
  • ISO as international standards (known as ISO 8802)


  • 802.1--overview of project 802, including higher layers and internetworking
  • 802.2-logical link control (LLC)
  • 802.3-carrier sense multiple access with collision detect (CSMA/CD), very similar to Ethernet
  • 802.4-token bus
  • 802.5-token Ring
  • 802.6-metropolitan area network
  • 802.7-broadband technology advisory group
  • 802.8-optical fiber technology advisory group
  • 802.9-voice/data integration on LANs
  • 802.10-standard for interoperable LAN security


Closely related to the IEEE 802 standards is a more recentlydeveloped low-level protocol standard known as fiber distributeddata interface(FDDI) developed by the American NationalStandards Institute (ANSI) and based on the use of fiber opticcable.

FDDI differs from the IEEE 802 standards at the physical layer andMAC sublayer, but is compatible with the IEEE standards at the LLCsublayer.

Αναγνωριστικό άρθρου: 103954 - Τελευταία αναθεώρηση: 07/30/2001 13:48:00 - Αναθεώρηση: 1.0

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