Commercial Internet eXchange

The Commercial Internet eXchange (CIX) was an early interexchange point that allowed the free exchange of TCP/IP traffic, including commercial traffic, between ISPs. It was an important initial effort toward creating the commercial Internet that we know today.

The goal of the CIX was to be an independent interconnection point with no U.S. government-defined "acceptable use policy" on the traffic that could be exchanged; and just as critical, a "no-settlement" policy between the parties exchanging traffic. The no-settlement policy became a "given" during the modern era of the Internet, but was immensely controversial at the time.

The early history of the Internet was dominated by U.S. government agencies such as ARPA/DARPA through ARPANET, the Defense Communications Agency (DCA) through MILNET, the National Science Foundation (NSF) through CSNET and NSFNET, the NSF sponsored regional research and education networks, and a handful of national networks sponsored by various federal government agencies. The focus of this group was either military/government or research and education communications, especially support for the separately funded NSF supercomputing initiatives that started after Nobel laureate Ken Wilson's testimony to Congress in the 1980s.

In general these federally supported networks did not allow commercial traffic that was not in direct support of a federal agency's mission or in support of research and education. There were of course many organizations that wanted access to the Internet, but did not do work directly for or with federal agency or in support of research and education.

In 1988, the Federal Networking Council allowed the Corporation for National Research Initiatives CNRI to develop a gateway between the commercial MCI Mail. It became operational in 1989. That same year, many other commercial e-mail providers got permission to build and operate similar connections, leading to the interconnection of many, heretofore disconnected e-mail services to become linked via the Internet.

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