•  10BASE5 also known as thicknet uses thick coaxial cable as the shared bus cable, 10 refers to the transmission speed of 10 Mbps, BASE refers to baseband and 5 refers to the maxium segment length of 5 meters. 10BASE5 standard is obsolete and replaced by newer standards due to the enhanced requirements by modern day networks
  •  10BASE2 also known as thinnet uses thin coaxial cable as the shared bus cable and runs at 10 Mbps. 10BASE is also obsolete now
  •  10BASE-T replaced 10BASE2 and 10BASE5 and uses twisted pair cables that can run distance up to 100 meters. Twisted pair cables are much thinner and flexible than coaxial cable which makes cable management and installation much easier. 10BASE-T runs at 10 Mbps and due to the growing needs of today’s LAN it is very rare. 10BASE-T is replaced by Fast Ethernet and Gigabit Ethernet standards.

Fast Ethernet: It refers to the Ethernet standards (802.3u) that support transmission speed of 100 Mbps.

Fast Ethernet specifications also include mechanisms for Auto-Negotiation of the media speed and duplex.

  •  100BASE-T replaced 10BASE-T and supports 100 Mbps transmission speed and segment length of 100 meters. Like 10BASE-T it uses twisted pair cabling
  •  100BASE-TX uses two wire-pairs inside Category 5 with one pair for each direction and thereby supporting full-duplex communication i.e 100 Mbps in each direction. This is the most widely deployed Fast Ethernet standard
  •  100BASE-T4 uses four wire-pairs; it can be implemented using category 3, 4 and 5 cables. 100BASE-TX is preferred over this standard.

Fast Ethernet standards also specify 100 Mbps communication using fiber-optic cables. 100BASE-FX uses single or multimode fiber cables and supports 100 Mbps full-duplex or half-duplex transmission.

Gigabit Ethernet: It refers to the Ethernet standards that support transmission speed of 1 Gbps over single/multimode fiber-optic cables and UTP cables.

  • 1000BASE-T also known as IEEE 802.3ab defines Gigabit Ethernet over UTP category 5, 5e or 6 cables. Like 100BASE-TX (Fast Ethernet) it supports maximum segment length of 100 meters and also supports Auto-Negotiation but unlike 100BASE-TX it uses all four wire-pairs of the UTP cable.

Gigabit Ethernet standard also specify 1 Gbps transmission speed using fiber-optic cables. 1000BASE-X is the collective term used to describe various options of 1 Gbps transmission over fiber-optic cable such as 1000BASE-SX, 1000BASE-LX and 1000BASE-LX10 etc.

10 Gigabit Ethernet (10 GigE): It refers to the Ethernet standards that support transmission speed of 10 Gbps which is 10 times faster than Gigabit Ethernet. It does not support CSMA/CD mechanism since it does not support half-duplex communication rather only full-duplex communication is supported.

  • 10GBASE-CX4 specifies 10GigE connectivity using copper cables with cables distances up to 15 meters. It was the first 10 GigE standard.
  • 10GSFP+Cu uses cooper twin-ax cables with SFP+ attached and connects directly into an SFP+ port. They are suitable for very short distances of up to 10m and offer a highly cost-effective way to connect servers and end-systems with 10GigE switches within racks and across adjacent racks.
  • 10GBASE-T specifies 10GigE connectivity using UTP and STP cables with cable distances up to 100 meters. It can utilize the existing 1000BASE-T cable infrastructure allowing from easier upgrade.

10 Gigabit Ethernet (10 GigE) standards that define 10 Gbps transmission over fiber-optic cabling includes

  • 10GBASE-SR which uses multi-mode fiber cabling with distances up to 26 meters. Using 2000 MHz*km MMF (OM3), up to 300m link lengths are possible.
  • 10GBASE-LR supports cable lengths of 10 kilometers on standard single-mode fiber.
  • 10GBASE-LR supports cable lengths of 10 kilometers on standard single-mode fiber.

There are other standards also such as 10GBASE-LRM, 10GBASE-ER etc.

Long Reach Ethernet: It was developed by Cisco Systems and supports 5-15 Mbps transmission speed over existing category 1, 2 and 3 cabling and up to 5000 feet. Cisco announced End-of-Sale of its LRE products in 2006 and VDSL solutions replaced this technology.

In this lesson we covered various physical layer standards of the Ethernet and in the upcoming lessons we will delve more into Ethernet technology.