By Light Professional IT Services LLC readies warfighters and federal agencies with technology and systems engineered to connect, protect, and prepare individuals and teams for whatever comes next. Headquartered in McLean, VA, By Light supports defense, civilian, and commercial IT customers worldwide. Perform engineering tasks to maintain a large, complex and highly resilient IP voice and video communications infrastructure. Manage, configure, troubleshoot and assure service supporting all aspects of a voice, video and data network. Must be organized, document oriented, possess skills in diagramming, and understand WAN principals. Perform system maintenance, support capacity planning activities and complete configuration change actions and documentation efforts. Configure and implement calling search spaces, route plans, route partitions, route lists and device profiles. Configure Cisco or Juniper routing and switching devices. Support distributed firewall infrastructure. Provide input in the development of technical policy, work instructions and reporting in support of an enterprise IP telephony network. Analyze and resolve complex technical problems utilizing foundational knowledge of SIP signaling and call-flows. Analyze and resolve remote site registration, signaling and media problems. Configure route plans, route lists, device profiles, calling search spaces, and route partitions. Validate change requests and ensure accuracy. Perform fault analysis and configuration of voice subscribers, call handlers and call routing rules. Perform fault analysis and configuration of Cisco and or Juniper routing and switching rules.