Microsoft KB Archive/103954
Article ID: 103954
Article Last Modified on 7/30/2001
This article was previously published under Q103954
IEEE Standard 802 for Local Area Networks
Recognizing a need for standards in the LAN market, the Institute of Electrical and Electronics Engineering (IEEE) undertook Project 802. Named for the year and month ('80 Feb) of its inception, Project 802 defined a family of low-level protocol standards at physical and data link layers of the OSI model.
In IEEE 802 terms, the OSI data link layer is divided into two sublayers: 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 802 include 802.3 CSMA/CD, 802.4 token bus, and 802.5 token ring. These standards differ at the physical layer and media access control sublayer, but are compatible at the logical link control 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)
PROJECT 802 OVERVIEW
- 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
ANSI FDDI STANDARD
Closely related to the IEEE 802 standards is a more recently developed low-level protocol standard known as fiber distributed data interface(FDDI) developed by the American National Standards Institute (ANSI) and based on the use of fiber optic cable.
FDDI differs from the IEEE 802 standards at the physical layer and MAC sublayer, but is compatible with the IEEE standards at the LLC sublayer.