DNI-U

A variety of networks operating in special security domains handle classified information in the United States or sensitive but unclassified information, while other specialized networks are reserved specifically for unclassified use by the same agencies. Some sites accessed from these networks have been referred to as "classified websites" in official communications, such as the American embassy "Amman's Classified Web Site at http://www.state.sgov.gov/pinea/amman/" and "Mexico City's Classified Web Site at http://www.state.sgov.gov/p/wha/mexicocity" Some of these trace back to the Defense Data Network which split from the Internet in 1983.

NIPRNet is a low-security network reserved for unclassified information, such as regular Internet websites and firewalled but unclassified military websites.

According to the U.S. Department of State Foreign Affairs Manual, "OpenNet is a physical and logical Internet Protocol (IP)-based global network that links the Department of State's Local Area Networks (LANs) domestically and abroad. The physical aspect of the network uses DTS circuits for posts abroad, FTS-2001-provided circuits, leased lines, and dial-up public switch networks. This includes interconnected hubs, routers, bridges, switches, and cables. The logical aspect of the network uses Integrated Enterprise Management System (NMS) and TCP/IP software, and other operational network applications. OpenNet is a Sensitive But Unclassified (SBU) network, which supports e-mail and data applications."

OpenNet+ is described for State Department use as using standard .state.gov domain names, which must be requested through a State Department intranet site at http://intranet.state.gov/ds3081 . Web site development cannot be done on machines directly connected to this network. The "www" prefix is not to be used on OpenNet+, as it is reserved for use on the Internet.

OSIS was the name of an "unclassified network serving the intelligence community with open source intelligence". Originally used to refer both to the network and to the content it provided, it has since been decoupled, with the content named "Intelink-U", while the network continues as DNI-U. The network is maintained by the DNI-CIO Intelligence Community Enterprise Services office (ICES).

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