This is a Sources Sought Notice for planning purposes only, seeking information from vendors registered under NAICS 541519 for full-service maintenance and support of Video Teleconferencing (VTC) and Secure Video Teleconferencing (SVTC) systems. The contractor must provide 5-day-a-week coverage with a 4-hour phone response and 24-hour onsite response for critical issues, plus a 72-hour response for non-critical problems. Support services include on-call, remote, and onsite troubleshooting, repair, and parts replacement. The performance period includes one 12-month base period and four one-year option periods. No budget amount or specific performance location is specified.