Senior Network Engineer (VoIP / SIP Network Support Engineer)

Lumiere Systems•Plano, TX

About The Position

We are seeking a highly skilled VoIP / SIP Network Support Engineer to support and troubleshoot real-time voice services in a production telecom environment. This role focuses on rapid incident triage, deep SIP and media analysis, and effective coordination with internal teams and external vendors to ensure high service availability and call quality. The ideal candidate has hands-on experience analyzing SIP signaling and media flows, understands telecom network behavior, and communicates clearly during high-severity incidents.

Requirements

Experience with Ribbon PSX, Neustar
Experience with industry-leading SBC platforms (Cisco, Ribbon/Sonus, Oracle/Acme Packet, AudioCodes)
Strong hands-on experience troubleshooting SIP and VoIP in carrier or enterprise environments
Ability to analyze SIP call flows, packet captures, and signaling logs
Solid understanding of telecom network behavior, including call routing and failure scenarios
Experience with monitoring systems, alert response, and incident triage
Working knowledge of RTP and media fundamentals (jitter, packet loss, QoS, MOS)
Strong understanding of SDP and codecs (G.711, G.729, Opus, DTMF)
Familiarity with SBCs and SIP trunking architectures
Experience with secure signaling and media (TLS/mTLS, SRTP)
Proven discipline in incident management, escalation, and follow-through
Excellent verbal and written communication skills, especially during high-severity incidents

Nice To Haves

Exposure to automation tools (e.g., Ansible, Python scripting)
Experience working with telecom carriers or managed voice service providers
Exposure to packet capture tools (e.g., Wireshark) and call analysis platforms
Experience supporting 24x7 or on-call production environments

Responsibilities

Troubleshoot complex SIP and VoIP issues impacting call setup, call quality, and service availability
Analyze SIP signaling flows, call traces, and logs to identify root causes and failure patterns
Monitor alerts, respond to incidents, and perform real-time issue triage in a production environment
Investigate RTP/media path issues, including jitter, packet loss, latency, QoS, and MOS degradation
Validate and troubleshoot SDP negotiations, codec selection, DTMF methods, and media compatibility
Support and coordinate SBC and SIP trunk operations, including interop issues with carriers and vendors
Work with secure voice implementations using TLS/mTLS for signaling and SRTP for media
Participate in incident management and escalation processes, ensuring proper ownership and resolution
Provide clear, concise incident communications to internal stakeholders, leadership, and external vendors
Contribute to post-incident reviews, documentation, and operational improvements