Defense Information Systems Network

The Defense Information System Network (DISN) has been the United States Department of Defense's enterprise network for providing data, video and voice services for 40 years.

The Defense Information System Network (DISN) is a worldwide-protected telecommunications network that enables the exchange of information in an interoperable and global space, partitioned by security demands, transmission requirements, and geographic needs of targeted end-user communities. The DISN offers a selection of integrated standards-based services to fulfill these connectivity needs. The services provide Defense Information Systems Agency (DISA) mission partners with capability options to support diverse telecommunication requirements for organizations focused on, but not limited to, the Department of Defense (DoD).

The DISN end-to-end infrastructure is composed of three major segments:

The DISN provides the following multiple networking services:

If you use the Defense Information System Network (DISN) for anything - to download the latest security patches, check webmail on Army Knowledge Online(AKO), view information on the AKO//Navy Knowledge Online (NKO)/Global Combat Support System – Air Force (GCSS-AF) portals, or analyze geospatial data dynamically on multiple National Geospatial-Intelligence Agency (NGA) systems – you've leveraged the Global Content Delivery Service (GCDS) without even realizing it. GCDS leverages commercial Internet technology to accelerate and secure DOD web content and applications across the Non-secure Internet Protocol Router Network (NIPRNet) and Secure Internet Protocol Router Network (SIPRNet) 24x7. GCDS’ global platform of hundreds of specially-equipped servers helps the Department of Defense Information Network (DODIN) withstand the crush of daily requests for rich, dynamic, and interactive content, transactions, and applications. When delivering on these requests, GCDS detects and avoids DODIN-related problem spots and vulnerabilities to ensure mission critical software downloads flawlessly, and applications perform reliably. The same platform also secures critical applications using its Web Application Firewall, allowing it to inspect web requests and detect application attacks before an organization’s web server and the data center is exposed to a possible threat. Furthermore, GCDS provides customers and security response teams with vital information that can be used to detect and block anomalous and potentially malicious attacks. Overall, GCDS provides the best user experience possible by not only increasing performance and availability anytime, anywhere for the warfighter, but also enhancing the security posture of an organization’s data center to ensure customer’s data is secured 24x7.

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