Expecting gigabit Ethernet to vanquish your LAN bandwidth problems?

Keep your excitement in check. While carefully implementing gigabit Ethernet can enhance overall network performance, the technology may not be the panacea you expect because your clients and servers probably aren’t powerful enough to take full advantage of its capabilities.

Gigabit Ethernet doesn’t have the contention problems of conventional Ethernet because it is usually deployed as a switched technology like 10Base-T and 100Base-T are. But other factors conspire to lower throughput.

Just how much lower was what we at West Virginia University’s (WVU) Advanced Networking Lab set out to determine. We intentionally side-stepped the issue of Jumbo Frames — use of which speeds gigabit Ethernet by reducing overhead — because we were curious to see what kind of performance we could achieve with plain vanilla gigabit Ethernet right out of the box.

At the same time WVU was conducting its performance tests, Brian Norris, a senior hardware engineer then working at Wandel & Goltermann, was independently testing bandwidth utilization and throughput on gigabit Ethernet and fast Ethernet links. When the two organizations met at the Gigabit Ethernet Conference in San Jose, Calif., we learned of each other’s testing and compared notes. Our results were surprisingly similar and not good news for organizations considering making the gigabit leap.