Currently, ManTech is seeking a motivated, mission oriented Senior Network Engineer in the Chantilly, VA area. As the Senior Network Engineer you will be responsible for designing, installing, and maintaining remote customer site and core data centers. The qualified professional should possess all necessary troubleshooting and problem-solving skills pertinent for a network configuration engineer as well as excellent written and verbal communication skills. Numerous career growth opportunities and training opportunities exist with this position. **Responsibilities include but not limited to:** + Designing network, VoIP, VTC, Cisco CMS and TMS and Cisco Call Manager (CUCM). + Analyzing and planning capacity growth and overall scalability of the network. + Responsible for the overall integration of a total network (black and red) including the design, installation, maintenance, management, and coordination of a moderately sized and constantly growing network with multiple external sites. + Creating and maintaining documentation, diagrams, and standard operating procedures + Working with the other internal support teams to devise solutions for complex operational problems within multiple data centers and a distributed IT infrastructure. + Providing guidance and training for network administrators, service desk personnel and junior engineers + Diagnosing, troubleshooting, and resolving issues related to a wide range of areas including initially setting up, maintaining, or recovering customer sites, Cisco VoIP, VTC, Cisco Data Center, Cisco Security, etc. + Efficiently resolving escalated trouble tickets + Ensuring the network environment has STIGs properly applied and implementing necessary security controls. + Providing client consulting and training on interfacing with various types of hardware and software + Participating on project teams responsible for a variety of engineering tasks + Attention to detail, ability to work independently, organization/time management skills. + Hardware Cisco Nexus 9200/9300/9500 series and Cisco 2960, 3850, 4331 switches **Basic Qualifications:** + Requires a bachelor’s degree in computer science or equivalent or at least 8 to 10 years’ experience with networking in VoIP, VTC, data circuits, MS Office including Visio, Word, and Excel. + Knowledge in voice technologies like Voice over IP, SIP, TCPIP, QOS, H.323, etc. + Up to 10% travel (Local from contractor location to customer location) + DoD 8140 IAT Level II required: Security+ CE and Computing Environment (CE) certification in Cisco technology (CCNA Voice) required and (CCNP) desired. + Cisco Collaboration certification a big plus + Cisco Data Center certification a plus + Cisco Security certification a plus + Excellent written and verbal communication. + Comfortable on the CLI + Comfortable interfacing with Government leadership + Able to work independently and in groups while in a fast-paced work environment. + Valid US Driver’s License- up to 10% local travel **Physical Requirements:** + Must be able to remain in a stationary position up to 75% of the time. + Must be able to move about inside the office to access file cabinets, office machinery. + Must be able to position self to maintain office supplies on variable height shelving. + The person in this position frequently communicates with co-workers, management, and customers, which may involve delivering presentations. + Must be able to exchange accurate information in these situations. + Must be able to observe and detect employee deviations from established policy. **Security Requirements:** + Active Top-Secret Clearance with investigation within 5 years. Active SCI or active SCI Eligibility required.