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CiX: Commercial Internet Exchange

Last Edit: 10/01/17

The Commercial Internet Exchange was created in the late 1980's as an Internet Exchange Point for early commercial Internet Service Providers (ISPs). In the 1980's - what was referred to as the Internet - was dominated by government sponsored agencies: specifically the NSFNET (National Science Foundation). The NSFNET had a prohibition on commerical use of it's backbone infrastructure; although the NSFNET had an 'acceptable use policy' which allowed commercial traffic on the network, so long as the commerical organisation supported educational research. Basically, commerical use of NSFNET was confused, and far from "open". Therefore, commercial networks which ran on TCP/IP (technology of the Internet) struggled to interconnect with the educational "backbone" infrastructure of the Internet. The Commercial Internet Exchange (CiX) was created so that these commercial networks (ISPs) could connect together and exchange traffic across their networks. The Commercial Internet Exchange played a critical role in decentralising the Internet. Eventually the Commercial Internet Exchange (CiX) was replaced by Internet Exchange Points (IXPs).