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Ethernet IEEE 802.3 Standards

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Ethernet IEEE 802.3 Standards

- a summary of the Ethernet, IEEE 802.3, standards and their release dates.


Ethernet, IEEE 802.3 tutorial includes:

Ethernet, 802.3 is defined under a number of IEEE standards, each reflecting a different flavour of Ethernet. One of the successes of Ethernet has been the way in which it has been updated so that it can keep pace with improving technology and the growing needs of the users.

As a result of this the IEEE standards committee for Ethernet has introduced new standards to define higher performance variants. Each of the Ethernet IEEE 802.3 standards is given a different reference so that it can be uniquely identified.

In addition to this the different IEEE 802.3 standards may be known by other references that reflect the different levels of performance. These are also defined below.


IEEE 802.3 standards

The IEEE 802.3 standard references all include the IEEE 802.3 nomenclature as standard. Different releases and variants of the standard are then designated by different designated letters after the 802.3 reference, i.e. IEEE 802.3*. These are defined in the table below.


STANDARD
SUPPLEMENT
YEARDESCRIPTION
802.3a198510Base-2 (thin Ethernet)
802.3c198610 Mb/s repeater specifications (clause 9)
802.3d1987FOIRL (fiber link)
802.3i199010Base-T (twisted pair)
802.3j199310Base-F (fiber optic)
802.3u1995100Base-T (Fast Ethernet and auto-negotiation)
802.3x1997Full duplex
802.3z19981000Base-X (Gigabit Ethernet)
802.3ab19991000Base-T (Gigabit Ethernet over twisted pair)
802.3ac1998VLAN tag (frame size extension to 1522 bytes)
802.3ad2000Parallel links (link aggregation)
802.3ae200210-Gigabit Ethernet
802.3as2005Frame expansion
802.3at2005Power over Ethernet Plus

Ethernet standards supplements and releases

New technologies are being added to the list of IEEE 802.3 standards to keep pace with technology.


Ethernet terminology

There is a convention for describing the different forms of Ethernet. For example 10Base-T and 100Base-T are widely seen in the technical articles and literature. The designator consists of a three parts:

  • The first number (typically one of 10, 100, or 1000) indicates the transmission speed in megabits per second.
  • The second term indicates transmission type: BASE = baseband; BROAD = broadband.
  • The last number indicates segment length. A 5 means a 500-meter (500-m) segment length from original Thicknet. In the more recent versions of the IEEE 802.3 standard, letters replace numbers. For example, in 10BASE-T, the T means unshielded twisted-pair cables. Further numbers indicate the number of twisted pairs available. For example in 100BASE-T4, the T4 indicates four twisted pairs.

The Ethernet IEEE 802.3 standards are continually being updated to ensure that the generic standard keeps pace with constant advance of technology and the growing needs of the users. As a result, IEEE 802.3, Ethernet is still at the forefront of network communications technology, and it appears it will retain this position of dominance for many years to come. In addition to the different IEEE 802.3 standards, the terminology used to define the different flavours is also widely used for defining which Ethernet variant is used.


출처 : http://www.radio-electronics.com/info/telecommunications_networks/ethernet/ethernet-ieee-802-3-standards.php

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