Unbound is being released as an open source alternative to the BIND domain name system (DNS) server -- makes its worldwide debut today with the public release of Unbound 1.0 at
Released to open source developers by NLnet Labs, VeriSign, Inc., Nominet, and Kirei, Unbound is a validating, recursive, and caching DNS server designed as a high-performance alternative for BIND (Berkeley Internet Name Domain). Unbound will be supported by NLnet Labs.
An essential component of the Internet, the DNS ties domain names (such as www.geekzone.co.nz) to the IP addresses and other information that Web browsers need to access and interact with specific sites. Though it is unknown to the vast majority of Web users, DNS is at the heart of a range of Internet-based services beyond Web browsing, including email, messaging and Voice Over Internet Protocol (VOIP) telecommunications.
The companies say that although BIND has been the de facto choice for DNS servers since the 1980s, a desire to seek an alternative server that excels in security, performance and ease of use prompted an effort to develop an open source DNS implementation. Unbound is the result of that effort. Mostly deployed by ISPs and enterprise users, Unbound will also be available for embedding in customer devices, such as dedicated DNS appliances and ADSL modems.
By making Unbound code available to open source developers, its originators hope to enable rapid development of features that have not traditionally been associated with DNS. One is an implementation of DNSSEC, a security enhancement that Unbound adds to the DNS protocol and that is essential to help protect DNS transactions. The only open source DNS implementations that support the DNSSEC standard are Unbound and BIND.
Unbound was architected in January of 2004 by Jakob Schlyter of Kirei and Roy Arends of Nominet. VeriSign and EP.Net funded development of the prototype, which was built by David Blacka and Matt Larson of VeriSign. Late in 2006, NLnet Labs joined the effort, writing an implementation in C based on the existing prototype and using experience NLnet Labs gained during the development of NSD, a DNS server targeted at information publishers.
During its development phase, Unbound was tested extensively at NLnet Labs. Meanwhile, a number of volunteers have deployed development releases in their labs and production networks.
Unbound runs on posix-based operating systems such as Linux, MacOS X, FreeBSD, and Solaris. The code, its documentation, and additional information are all freely available for download.