Gigabit Ethernet - more speed at the backbone

The Evolution of Ethernet

Ethernet is the most popular cabling technology for local area
networks. Initially, the most commonly installed Ethernet systems were called 10BASE-T,
which provided transmission speeds of up to 10 Mbps. As data zipping across LANs got
thicker, 10BASE-T gave way to 100BASE-T, also known as Fast Ethernet, which could
(theoretically) transmit at 100 Mbps. Fast Ethernet uses the same cabling as 10Base-T,
while everything else -- the packet format and length, error control, and management
information -- remained the same. Its scalability ensured its quick adoption.

Fast Ethernet was typically used for backbones, but the ever-prevailing bandwidth crunch
has pushed 100BASE-T onto workstations. Its now giving up its place at the backbone to
Gigabit Ethernet which can (theoretically) provide a bandwidth of a billion bits per second.

Enterprise proposes, GE disposes

Applications in the modern enterprise make exacting demands from
the network, and put a lot of pressure on the desktop, server, hub, and the switch for
increased bandwidth. Megabytes of data will have to flow unhindered across intranets as
communication within enterprises will move on from text-based e-mail messages to
bandwidth-intensive real-time audio, video and voice.

An increasing number of enterprises are employing href="https://www.ciol.com/content/technology/elinks/99051501.asp">data warehousing for strategic
planning. This implies increased volumes of data and low transmission latency. These
warehouses may comprise of terabytes of data distributed over hundreds of platforms and
accessed by thousands of users, and must be updated regularly to provide users
near-real-time data for critical business reports and analyses.

Archiving an enterprise's mission critical information
scattered across a network usually occur during off hours. Even then, it requires large
amounts of bandwidth for a fixed period of time (4 to 8 hours). The backup involves
gigabytes or terabytes of data distributed over hundreds of servers and storage systems
throughout an enterprise.



Enterprise critical applications will proliferate and demand ever greater shares of
bandwidth at the desktop. As the number of users grows rapidly, enterprises will need to
migrate critical portions of their networks (if not the whole network itself) to
higher-bandwidth technologies. Crossing over from megabit to gigabit Ethernet will be
inevitable, starting at the backbone.

The Transition to GE

A very straightforward upgrade scenario is upgrading 100 Mbps links between Fast
Ethernet switches or repeaters to 1000 Mbps links between 100/1000 switches. Such
high-bandwidth, switch-to-switch links would enable the 100/1000 switches to support a
greater number of both switched and shared Fast Ethernet segments.

GE will find it's early takers at campuses requiring greater
bandwidth between routers, switches, hubs, repeaters, and servers. Examples include
switch-to-router, switch-to-switch, switch-to-server and repeater-to-switch connections.
Initially, one cannot expect GE to be deployed widely at the desktop. In all scenarios the
network operating system (NOS), applications and network interface card (NIC) drivers at
the desktop will remain unchanged. The MIS manager can also leverage not only the existing
multimode fiber, but also the current investment in network management applications and
tools. That's what makes upgrading to GE so attractive.