UK start-up 3C has launched what it calls the world's fastest authoritative DNS server, capable of answering over a million queries per second on a single CPU.

The company described the product, named 3C-DNS, as an "order-of-magnitude performance improvement" over any other single appliance. The key technology is its so-called network stack which works alongside the underlying operating system's network stack to provide high performance for certain classes of network service, including DNS, said 3C.

The technology, dubbed High Performance Network Stack or HPNS, is a network stack written from the ground up to add performance to applications such as VoIP, media streaming and DNS. These receive and transmit large numbers of small packets, which is the worst case for most operating systems, and which require context switches from user-mode to kernel and back again for each packet sent or received. According to 3C, HPNS cuts this overhead to a minimum, allowing much higher performance than conventional network stacks.

3C-DNS is supplied as a 1U appliance, containing two completely separate servers, which provides up to four gigabit Ethernet ports to handle DNS traffic. It uses standard BIND zone files for configuration, meaning that it is usually a drop-in replacement for older DNS servers. It costs £2,995.

“DNS is right at the heart of the internet”, said David Knell, 3C's CEO, “but is often overlooked until it goes wrong. 3C-DNS' performance makes it highly resistant to DDoS attacks and, by isolating external network traffic from the underlying operating system, HPNS removes the risk of the system being compromised through operating system vulnerabilities.”