3.1 Technologies for WAN and Backbone Networks - Gigabit Ethernet

Here is the overview of the presented content for Gigabit Ethernet part.

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Gigabit Ethernet
Example
MAC
Frame Bursting
Media-Independent Interface
Media
AutoNegotiation
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Gigabit ethernet is various technologies for transmitting Ethernet frames at a rate of a gigabit per second (1000Mbps). It uses Ethernet frame format and MAC technology. Because it uses MAC technology, when using gigabit ethernet to form subnet, delivering of data packet can be done through repeaters, hubs, bridges and switches, but not by IP routers. An IP router may interconnect several subnets.

The Media Access Control (MAC) data communication protocol sub-layer, also known as the Medium Access Control, is a sublayer of the Data Link Layer specified in the seven-layer OSI model (layer 2).

The Carrier Sense Multiple Access with Collision Detection (CSMA/CD) protocol is defined in the MAC sublayer and support collision is each collision domain.

Ethernet supports a variet of physical mdeia, like normal copper cable and high speed optical fiber and etc. This is possible because of the Media-Independent Interface (MII) below the MAC sublayer. Now in Gigabit Ethernet, MII have been enchanced and termed with Gigabit Media-Independent Interface (GMII). GMII is backward compatible with MII.

With the use of AutoNegotiation, Gigabit Ethernet can with different speed of UTP cable media (i.e: 10/100/1000). The lowest speed of all will be taken using roughly 40ms after cables are plugged in/out.