DISA eyes a cloud-focused future with DOD Enterprise Email decommission


Office of Strategic Communication and Public Affairs
December 7, 2022 

DISA decommissioned the DEE system in November after more than a decade of operation.

On Nov. 30, the Defense Information Systems Agency fully decommissioned the Department of Defense’s first department-wide, on-location email system known as “DOD Enterprise Email,” or DEE.

Pioneered over a decade ago by DISA and the U.S. Army, DEE was the precursor to the current era of scalable, cloud-based systems that are now used across the department.

As technology and the U.S. military’s requirements evolved, so did DISA, by anticipating the warfighter’s future needs in cyberspace. 



Advances in cloud computing and technology enabled DISA to migrate DEE users from on-premises email systems into shared cloud environments.

"These cloud solutions, such as DOD365-Joint, or DOD365-J, offer enterprise communication and collaborative functionality with self-governing control for the military services, ensuring the maximum capability of tools is in the hands of the war fighter,”

said Carissa Landymore, program manager for DISA’s Defense Enterprise Office Solution, or DEOS. “But also, with cloud-based services, you get a whole host of other capabilities and tools that were not originally provided with DEE.”

DOD365-J, which falls under DISA’s DEOS program, is a cloud-operated, Software as a Service enterprise system that offers a full office suite of Microsoft 365 applications, including email, productivity tools and Microsoft Teams. It’s in a single cloud, managed by DISA and more than 77 agencies and combatant commands, including the White House and Pentagon.

DOD365-J allows users to seamlessly collaborate and share information across the department in a secure, cost-effective and accessible manner. DEOS enables the DOD to operate and fight worldwide by reducing the IT footprint and streamlining information access and sharing, while strengthening cybersecurity.

DOD’s adoption of cloud-based technology has transformed the DOD workplace by increasing efficiency, enhancing team productivity, and providing warfighters and users security and flexibility to meet the mission in the field, remote locations, or at home.

DISA has helped DOD organizations to standardize cloud adoption, collaborate across departments, and integrate multiple capabilities. DISA will continue to replace legacy applications with standard cloud-based capabilities for the department, when appropriate or necessary.



Future capabilities include (1) the DOD365 Integrated Phone System, which is an enterprise-wide virtual telephone service through DOD365 Teams, and (2) DOD365-Secret, or SEC, which will be the first classified cloud for DOD.

Today, DOD’s classified network lacks classified collaboration capabilities to meet warfighter and DOD mission needs. DISA’s DOD365-SEC will bring the classified workspace into the 21st century to operate ahead of the adversary by allowing users to communicate and collaborate virtually through Microsoft Teams. Cybersecurity is at the foundation of DOD365-SEC, offering integrated security tools like cloud security assessment, compliance monitoring, and threat detection.

DISA’s deployment of DOD365-SEC will provide users with similar features to DOD365-J to accomplish their mission anytime, anywhere. With enhanced security features to protect the warfighter and their data, DOD365-SEC, once deployed, will enable the warfighter to operate and fight worldwide by accessing mission-critical information from a classified cloud environment. With the implementation of DOD365-SEC, DISA will be able to decommission DEE-Classified in fiscal year 2024.

DISA and the DOD chief information officer, in partnership with Microsoft, have collaborated between the public sector and private industry to maximize the delivery of cutting-edge cloud services for communication, collaboration and productivity without compromising security.



In 2011, DISA deployed DEE as the first, secure enterprise-wide email solution for the DOD. It was designed to increase operational efficiency and facilitate collaboration across the department.

It was the largest non-commercial (non-Gmail, Hotmail, AOL, etc.) email deployment in the world with a userbase peaking at 1.8 million. Additionally, DISA’s mobile solutions allowed access to DEE for more than 80,000 mobile users, which was the largest single mobile device deployment in the world at the time.

“[DOD] Enterprise Email has proven to be one of DISA’s greatest achievements,”

said Tony Montemarano, former DISA executive deputy director when the program announced its sunset.

At launch, DEE was developed as it was deployed, without boundaries, both inside of DISA and across the DOD. While DEE was successful, its true legacy was paving the way for future enterprise-wide, cloud-based solutions such as DOD365-J, which DISA has successfully deployed for more than 100,000 users.




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