VoIP Systems Engineer

ManTech International seeks a VoIP Systems Engineer to design, secure, and sustain enterprise voice solutions supporting U.S. defense and federal missions. You will architect and maintain VoIP infrastructure, optimize call quality, integrate with LAN/WAN and collaboration platforms, and ensure compliance with federal security standards. Partner with cyber, systems, and network teams to troubleshoot complex issues, lead upgrades, and document solutions. ManTech offers mission-focused work, stron…