Bifrost is a light weight distribution of Linux

Linux distribution

A Linux distribution is a member of the family of Unix-like operating systems built on top of the Linux kernel. Such distributions are operating systems including a large collection of software applications such as word processors, spreadsheets, media players, and database applications...

 optimized for networking

Computer network

A computer network, often simply referred to as a network, is a collection of hardware components and computers interconnected by communication channels that allow sharing of resources and information....

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It is named after Bifröst

Bifröst

In Norse mythology, Bifrost or Bilröst is a burning rainbow bridge that reaches between Midgard and Asgard, the realm of the gods...

, the bridge which connects the world and the land of Gods in Norse mythology

Norse mythology

Norse mythology, a subset of Germanic mythology, is the overall term for the myths, legends and beliefs about supernatural beings of Norse pagans. It flourished prior to the Christianization of Scandinavia, during the Early Middle Ages, and passed into Nordic folklore, with some aspects surviving...

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Primary Usage

Since the intended use is network infrastructure, reliability is the number one priority with performance a close second. It is trusted with mission critical deployments where uptime is measured in years.

The two most common uses are as Edge Router or NAC

Network Access Control

Network Access Control is an approach to computer network security that attempts to unify endpoint security technology , user or system authentication and network security enforcement.-Background:Network Access Control is a computer networking solution that uses a set of protocols to define and...

 / Captive portal

Captive portal

The captive portal technique forces an HTTP client on a network to see a special web page before using the Internet normally. A captive portal turns a Web browser into an authentication device. This is done by intercepting all packets, regardless of address or port, until the user opens a browser...

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Both of these uses often also perform at least basic firewall

Firewall (computing)

A firewall is a device or set of devices designed to permit or deny network transmissions based upon a set of rules and is frequently used to protect networks from unauthorized access while permitting legitimate communications to pass....

 functions.

History

The first version of the Bifrost firewall was installed at The Department of Chemistry, Swedish University of Agricultural Sciences

Swedish University of Agricultural Sciences

The Swedish University of Agricultural Sciences or Sveriges Lantbruksuniversitet is a university in Sweden. Although its head office is located in Ultuna, Uppsala, the university has several campuses in different parts of Sweden, the other main facilities being Alnarp in Lomma Municipality, Skara,...

 in the year 1997.

Present

Currently the development, testing and packaging is housed at Uppsala University

Uppsala University

Uppsala University is a research university in Uppsala, Sweden, and is the oldest university in Scandinavia, founded in 1477. It consistently ranks among the best universities in Northern Europe in international rankings and is generally considered one of the most prestigious institutions of...

with contributions from many other. The university also runs several installations where Bifrost is used. Bifrost is also used as a base for an authetication service, which make it possible to log in to the net.