Another company has entered the market for preventing denial-of-service attacks, claiming to be faster by having learnt lessons from those before it.

Launching the IG200 and IG2000 at the NetWorld+Interop show this week, start-up IntruGuard Devices explained that its rate-based equipment sits between servers and the Internet, cutting off server-bound traffic that exceeds customer-set thresholds, and so indicates a DoS attack may be underway.

What sets IntruGuard apart from other vendors such as Captus, DeepNines, Top Layer and Vsecure though is that it has developed chips to handle traffic sorting and has the benefit of seeing what other vendors have tried, said Rodney Thayer, a network security consultant with Canola-Jones Internet Investigations.

All products use policies to limit traffic that can reach servers, and each has its own set of tools for defining traffic to be controlled and what to do when limits are exceeded. Some also add other security options such as firewalls.

Beta tester Fiber Internet Center said in tests that the IG2000 cut off DoS attacks nearly 30 seconds faster than an Extreme Networks' Black Diamond switch. The IG200 and 2000 can set up to eight different rate policies based on Layer 2, 3 and 4 parameters for different sets of servers that a single box could protect.

Both products will be available in July and aimed at centre of the market, with the Fast Ethernet IG200 costing $12,000 (£6,800) and the Gigabit Ethernet IG2000 $25,000 (£14,100).