Initially, single mode and multi mode fiber and short haul coaxial cable will be supported. Standards for twisted pair cables are expected by 1999. The standard uses physical signaling technology used in Fiber Channel to support Gigabit rates over optical fibers. At first, Gigabit Ethernet is expected to be deployed as a backbone in existing networks. It can be used to aggregate traffic between clients and "server farms", and for connecting Fast Ethernet switches. It can also be used for connecting workstations and servers for high bandwidth applications such as medical imaging or CAD [1]. .
However, the increase in speed brings many changes to the original Ethernet standard, even though it maintains the same CSMA/CD protocol, frame format and frame size. Therefore, adaptation will be necessary in many areas, such as cabling, switch and router hardware, and network topology [2].
The first two sections of the paper present a brief description of Ethernet, and a more detailed description of Gigabit Ethernet, respectively. Then, these standards are compared and the differences analyzed for significance.
ORIGINAL ETHERNET (IEEE 802.3).
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Ethernet is the least expensive high speed LAN alternative. Ethernet uses CSMA/CD protocol in the MAC(Medium Access Control) Sublayer. This stands for "Carrier Sense, Multiple Access, Collision Detect". An Ethernet station sends data at a rate of 10 megabits per second. That bit allows 100 nanoseconds per bit. However, an Ethernet cable can run for hundreds of feet. Therefore, if two stations are located, say, 250 feet apart on the same cable, and both begin transmitting at the same time, then they will be in the middle of the third bit before the signal from each reaches the other station. This explains the need for the "Collision Detect" part. Two stations can begin to send data at the same time, and their signals will collide nanoseconds later. When such a collision occurs, the two stations stop transmitting, and try again later after a random delay period.
