 PLANO, Texas, May 18, 2021 PRNewswire -- Ribbon Communications Inc. Nasdaq: RBBN, a global provider of real time communications software and IP optical networking solutions to service providers, enterprises, and critical infrastructure sectors, today announced that its Session Border Controller 5400 has been certified by the U.S. Department of Defense DoD as part of secure Microsoft Teams deployments across all DoD agencies and within its communications network. The U.S. DoD Defense Information Systems Agency DISA Joint Interoperability Test Command JITC certification is the culmination of a rigorous process that tests solutions for quality, security, interoperability and reliability. 