Engineer, Managed Services Monitoring (Remote)

ManTech International is seeking a Telephony Engineer to support our Information Technology organization, enabling secure, reliable voice services that underpin mission-critical national security programs. In this role, you will design, implement, and support enterprise telephony and VoIP solutions for U.S. intelligence, Department of Defense, and other federal customers, ensuring that voice communications remain highly available, resilient, and secure. Working within ManTech’s culture of innovation, integrity, and respect for individual contributions, you will collaborate closely with network, systems, and cyber security engineers to deliver integrated, cutting-edge communication capabilities.

As a Telephony Engineer, you will be responsible for the architecture, configuration, and day-to-day administration of PBX and VoIP platforms, including call routing, SIP trunking, voicemail, and contact center features across multiple, geographically dispersed sites. You will troubleshoot complex call quality and signaling issues, perform capacity planning, and drive lifecycle upgrades and migrations to modern unified communications solutions. Because our customers operate in highly sensitive environments, you will build and maintain telephony solutions that align with rigorous security standards, working in concert with ManTech cyber security teams to apply hardening, encryption, and continuous monitoring practices.

You will create and maintain detailed technical documentation, diagrams, and runbooks; contribute to standards and best practices; and provide subject-matter expertise during architecture reviews and incident response. This position offers the opportunity to work on challenging, large-scale systems that directly support national security missions, while growing your skills with advanced voice, collaboration, and security technologies. ManTech offers competitive compensation, comprehensive benefits, and a long-term career path for engineers who are passionate about enabling secure communications for those who protect our nation.