Q. What is Gigabit Ethernet?
A. As the name suggests this is the Ethernet networking protocol built for speed. Originally created in the 1970s by Valley’s networking firms, Ethernet ran at 10Mbps and provided fast file- and resource-sharing between networked PCs. It was, in short, the cornerstone of the LAN (local area network).

By the mid-90s – having beaten off Token Ring as the protocol of choice – it won out against HP-backed VG AnyLan to become the de facto 100Mbps technology. Gigabit and multiple Gigabit Ethernet are the natural successors.

Q. So it’s a LAN technology, right?
A. It was, and still is. But now suppliers are pitching forthcoming 10 Gigabit Ethernet as a technology that meets bandwidth needs beyond the campus both as a metropolitan area network (MAN) solution and a wide area network (WAN) solution.

Q. What long-distance application demands is it meeting?
A. Large file transfer, off-site storage, disaster recovery, video conferencing and other streaming applications. If you need to do any of these from office to office within a metropolis or even longer distances then 10 Gigabit Ethernet is worth considering.
More interestingly, perhaps,10 Gigabit Ethernet is being seen as the technology that will give the internet a ‘leg up’ in metropolitan areas.

By providing a much-needed injection of speed, this so-called ‘inter-POP’ application offers fast throughput between data centres, collocation facilities and carrier POPs (point of presence). For those considering hosted applications provided by ASPs the added bandwidth 10 Gigabit Ethernet promises could be a very attractive proposition.

Q. Aren’t there protocols providing this kind of bandwidth already?
A. There are, most notably Sonet/SDH (synchronous digital hierarchy), a transmission standard used by many of the world’s carriers. Supporters of the Ethernet approach say their technology is lower cost, easier to manage and upgrade and provides one large pipe from the LAN to the WAN allowing users to run applications across long distances that were originally the domain of a single building.

Dissenting voices point to the problem of packet loss and the inability to deliver decent quality of service (QoS). The Ethernet camp acknowledges these drawbacks and is working on two standards it hopes will assuage user fears. Namely, Resilient Packet Ring (RPR) which should solve the first problem and ITU x.86 which addresses the second.

Q. So, 10 Gigabit Ethernet runs at 10Gbps?
A. Not exactly. As with all networking protocols 10Gbps refers a theoretical maximum throughput. In practice latency, interference and the need to partition the network for priority jobs means bandwidth utilisation is never 100 per cent.

Q. When will 10 Gigabit Ethernet be available?
A. In its standardised form not until June 2002 at the earliest. That’s the date the IEEE (the Institute of Electrical and Electronics Engineers) has set for ratifying the technology. If past experience is anything to go by, however, suppliers are likely to have pre-standard equipment available long before then, probably by the end of 2001. As before, pre-standard network interface cards (NICs), switches and routers will be sold with the guarantee of upgrades once the standard is finalised.

Q. Will it be a success?
A. That’s up to you. If the demand for applications (discussed above) is as strong as the suppliers believe, then the answer is yes. If however video streaming and hosted applications – to name but two – fail to inspire corporate users then 10 Gigabit Ethernet could become another technology forlornly looking for an application.

The Dell’Oro Group is taking the optimistic line. It forecasts that revenues fro 10 Gigabit Ethernet products and services will rise from $500m in 2002 to $2.6bn by 2004.

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**Essential Links**

From the silicon.com archive
Broadband battle of Hastings on the horizon
LAN just a flash in the pan
load of this: Cisco claims cure for bandwidth woes

External Links
The Gigabit Ethernet Alliance
The official IEEE website
CERN Gigabit Ethernet Information
Network Professional Association