*US Citizenship Required *On-site in Fairfax, Virginia, only Think Tank is a woman-owned small business with more than 27 years of proven success delivering exceptional IT and consulting services to the federal government. We are currently seeking an ideal candidate for the position of Senior Network Infrastructure Engineer (5 years) to support a high-impact staff augmentation project with Fairfax County, Virginia. This position is conditional upon contract award expected in September / October 2025. Résumé of successful candidate(s) will be included with our proposal. The requirements are as follows: - Registered Communications Distribution Designer (RCDD) certification required. - At least five (5) years of experience with IT systems and technology in a telecom environment which includes both Legacy switching and the Next Generation technologies. - Knowledge and experience with configuration and maintenance of: gateways, routers, switches, firewall, DNS, DHCP, network servers, multiplexers, calling card platforms, TDM, Dialogic, VoIP systems (SIP, H.323 protocols, dial peers, and VoIP carrier trunking). - Sample Duties: Provides support in the translation of business requirements into telecommunications (e.g., LAN, CAN, WAN, voice and video) requirements, designs and orders. - Also, provides in‐depth engineering analysis of telecommunications alternatives for government public safety agencies in support of strategic modernization efforts and telecommunications enhancement design for medium and large scale telecommunication infrastructures. - Designs supporting cable/wiring infrastructure for construction projects that includes voice, data, video and wireless Supervises projects and staff and other personnel. - Provide overall program management services including making presentations to national, state and local officials.