| Ethernet's history is colorful . Its conception occurred at the Xerox Palo Alto Research Center (PARC), developed by Bob Metcalfe in 1972. In 1979, Digital Equipment Corp., Intel, and Xerox standardized the DIX V1.0 frame; two years later, they refined it with the Version 2.0 frame. In 1981, the Institute of Electrical and Electronic Engineers (IEEE) project 802 decided to form the 802.3 subcommittee, which is almost synonymous with the Ethernet that we know today. Table 2-1 provides a great description of the evolution of the Ethernet standard; this standard can be found in its original form in Switched, Fast, and Gigabit Ethernet , 3rd edition, by Robert Breyer and Sean Riley. Breyer and Riley refer to Ethernet as an evolutionary protocol versus a revolutionary protocol. Evolutionary innovations build on the current installed base and provide some form of migration path . As a revolutionary protocol, it will have some form of radical breakthrough that usually does not build on the current infrastructure. Ethernet is more than 25 years old and still is building a clear future for local-area networks. For further reading on the history of Ethernet, the 100-Mbps wars, and Gigabit Ethernet standards, see Switched, Fast, and Gigabit Ethernet , 3rd edition, by Robert Breyer and Sean Riley. NOTE The IEEE name convention works in the following manner. In the name 10Base-T, the 10 indicates the transmission speed in megabytes per second. The Base indicates baseband transmission. The T stands for unshielded twisted-pair cable, while F stands for "fiber." Early versions of Ethernet used a number to indicate cable segment length, such as 10Base-5 and 10Base-2, but this naming convention had to be dropped because of Ethernet's capability to have multiple cable lengths running on the same standard.
Table 2-1. Evolution of the Ethernet Standard | Colloquial Ethernet Standard | Official Ethernet Abbreviation | IEEE Spec. Supplement | Speed (Mbps) | LAN Topology | Segment Length in Meters | Medium Support | | Thick Ethernet | 10Base-5 | 802.3 | 10 Mbps | Bus | 500 m | 50-ohm coaxial (thick) | | Thin Ethernet/Thinnet | 10Base-2 | 802.3a | 10 Mbps | Bus | 185 m | 50-ohm coaxial (thin) | | Broadband Ethernet | 10Broad-36 | 802.3b | 10 Mbps | Bus | 1800 m | 75-ohm coaxial | | 10-Mbps Repeaters | Repeaters | 802.3c | 10 Mbps | Bus | ” | 50-ohm coaxial (thick/thin) | | Fiber- optic Inter-Repeater Link | FOIRL | 802.3d | 10 Mbps | Star | 1000 m | Optical fiber | | StarLAN | 1Base-5 | 802.3e | 1 Mbps | Star | 250 m | 100-ohm two-pair Cat 3-UTP | | StarLAN Multipoint | 1Base-5 | 802.3f | 1 Mbps | Star | 250 m | 100-ohm two-pair Cat 3-UTP | | Layer Management | | 802.3h | 10 Mbps | ” | ” | ” | | Twisted-Pair Ethernet | 10Base-T | 802.3i | 10 Mbps | Star | 100 m | 100-ohm two-pair Cat 3 | | Fiber Ethernet | 10Base-F | 802.3j | 10 Mbps | Star/bus | < 2000 m | Optical fiber | | Layer Management for 10-Mbps Repeaters | | 802.3k | 10 Mbps | Star | ” | ” | | 10Base-T Protocol Implementation Conformance Statement (PICS) | 10Base-T PICS | 802.3l | 10 Mbps | Star | < 2000 m | Multimode or single-mode fiber | | Second Maintenance Ballot | | 802.3m | 10 Mbps | ” | ” | ” | | Third Maintenance Ballot | | 802.3n | 10 Mbps | ” | ” | ” | | Layer Management for MAUs | | 802.3p | 10 Mbps | ” | ” | ” | | Guidelines for Development of Managed Objects (GDMO) | | 802.3q | ” | ” | ” | ” | | 10Base-5 PICS | 10Base-5 PICS | 802.3r | 10 Mbps | ” | ” | ” | | Fourth Maintenance Ballot | | 802.3s | 10 Mbps | ” | ” | ” | | 120-Ohm Cables for 10Base-T | | 802.3t | 10 Mbps | ” | 100 m | 120-ohm two-pair Cat 3 UTP | | Fast Ethernet | 100Base-TX | 802.3u | 100 Mbps | Star | 100 m | 100-ohm two-pair Cat 5 UTP | | Fast Ethernet over Cat 3 | 100Base-T4 | 802.3u | 100 Mbps | Star | 100 m | 100-ohm four-pair Cat 3 UTP | | Fast Ethernet over Fiber | 100Base-FX | 802.3u | 100 Mbps | Star | < 2000 m | Optical fiber | | 150-Ohm Cables for 10Base-T | | 802.3v | 10 Mbps | ” | 100 m | 150-ohm two-pair Cat 3 UTP | | Enhanced MAC or Binary Logarithmic Arbitration Method | BLAM | 802.3w | ” | ” | ” | ” | | Full-Duplex/Flow Control | FDX | 802.3x | 10 Mbps | ” | ” | ” | | Fast Ethernet over Two-Pair Cat 3 | 100Base-T2 | 802.3y | 100 Mbps | Star | | 100-ohm two-pair Cat 3 UTP | | Gigabit Ethernet Short Haul | 1000Base-SX | 802.3z | 1000 Mbps | Star | 300 m | Multimode fiber | | Gigabit Ethernet Long Haul | 1000Base-LX | 802.3z | 1000 Mbps | Star | 550 m | Multimode fiber | | Gigabit Ethernet | 1000Base-CX | 802.3z | 1000 Mbps | Star | 3000 m 25 m | Single-mode fiber Twin-ax 150-ohm copper | | Fifth Maintenance Ballot | 100Base-T | 802.3aa | 100 Mbps | ” | ” | ” | | Gigabit Ethernet for Cat 5 | 1000Base-T | 802.3ab | 1000 Mbps | Star | 100 m | Cat 5 UTP Cat 5e | | VLAN Frame Extension | VLAN | 802.3ac | ” | ” | ” | ” | | Trunking | Link aggregation | 802.3ad | ” | ” | ” | ” | | 10 Gigabit Ethernet [*] | 10000Base | 802.3ae | 10,000 Mbps | Star | 100 m “300 m 2 km “40 km | Multimode fiber Single-mode fiber | | VLAN Tagging | VLAN tagging | 802.1Q | ” | ” | ” | ” | | Secure Data Exchange SDE | Secure VLANs | 802.10 | ” | ” | ” | ” | | Traffic Expediting | Priority switching | 802.1p | ” | ” | ” | ” | | MAC Bridges, Spanning Tree | MAC bridges | 802.1D | ” | ” | ” | ” | [*] 802.ae is not in its final form, but the drafts indicate these operating specifications |
