Senior Network Engineer (VoIP / SIP)

Senior Network Engineer (VoIP / SIP Network Support Engineer)

Client: Financial Location: North America (on site Jersey City, NJ; Plano, TX; Columbus, OH) Work Hours: 8 AM – 5 PM EST

Overview: 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.

Key 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 Client 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

Required Qualifications:

• Experience with Ribbon PSX, Neustar
• Experience with industry-leading client 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 clients 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

Preferred Skills:

• 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