Monday, 23 March 2015

Practical number 3

Practical number 3

Definition: Ethernet is a physical and data link layer technology for local area networks (LANs). Ethernet was invented by engineer Robert Metcalfe.
When first widely deployed in the 1980s, Ethernet supported a maximum theoretical data rate of 10megabits per second (Mbps). Later, so-called "Fast Ethernet" standards increased this maximum data rate to 100 Mbps.

Ethernet II / DIX / 802.3

Ethernet II is a revised version of Ethernet rewritten by with Digital Equipment Corp,Intel, and Xerox. Ethernet II, also known as DIX, and 802.3.

Fast Ethernet / 100BASE-T / 802.3u

Fast Ethernet is also referred to as 100BASE-T or 802.3u and is a communications protocol that enables computers on a local-area network to share information with one another at rates of 100 million bits per second instead of the standard 10 million BPS. Fast Ethernet works over Category 5 twisted-pair wiring.

There are two available 100BASE-T standards. The first standard known as 100BASE-Tutilizes CSMA/CD. The second standard, known as 100VG-AnyLAN or 802.12, is similar to the other standard; however, it utilizes a different Ethernet frame to send its data.
100BASE-T is available in three different cable technologies:
1.       100BASE-T4 = Utilizes four pairs of telephone-grade twisted-pair wire and is used for networks that need a low-quality twisted-pair on a 100-Mbps Ethernet.
2.      100BASE-TX = Developed by ANSI 100BASE-TX is also known as 100BASE-X, 100BASE-TX uses two wire data grade twisted-pair wire
3.      100BASE-FX = Developed by ANSI, 100BASE-FX utilizes 2 stands of fiber cable.

Ethernet SNAP

Ethernet SNAP is short for Ethernet SubNetwork Access Protocol and is an Ethernet protocol that enabled old and new protocols to be encapsulated in a type 1 LLC.

Gigabit Ethernet / 1000BASE-T / 802.3z / 802.ab

Gigabit Ethernet is also known as 1000BASE-T or 802.3z / 802.3ab is a later Ethernet technology that utilizes all four copper wires in a Category 5 (Cat 5 & Cat 5e) capable of transferring 1 Gbps

10 Gigabit Ethernet / 802.3ae

10 Gigabit Ethernet (10GE or 10GbE or 10 GigE) is also known as 802.3ae is a new standard that was published in 2002 and supports up to 10 Gb/s transmissions. 10 gigabit Ethernet defines only full duplex point to point links which are generally connected by network switches unlike previous Ethernet standards. Half duplex operation, CSMA/CD (carrier sense multiple access with collision detection) and hubs do not exist in 10GbE.


A copper cable gigabit Ethernet standard that is no longer used. This standard has been replaced by 1000BASE-T.


A fiber optic gigabit Ethernet standard that operates over single-mode fiber.


A fiber optic gigabit Ethernet standard that operates over multi-mode fiber with typical distances of up to 550 meters (1804 feet)

Ethernet adapter

An Ethernet adapter or Ethernet controller is a term used to describe an Ethernet network card used to connect a desktop computer to a network.