Role objective
Own troubleshooting of SBC, firewall, NAT, routing, proxy, QoS, session handling, and network path issues impacting voice and real-time communications. The engineer should be able to work directly with enterprise customer network teams, understand their topology, ask the right questions, and quickly isolate whether the issue is caused by firewall, routing, SBC policy, NAT behavior, proxy, or WAN conditions.
Key responsibilities
- Troubleshoot SBC, SIP trunk, proxy, firewall, NAT, VPN, and edge-routing issues affecting voice and WebRTC traffic.
- Analyze one-way audio, no-media, SIP signaling failure, packet loss, jitter, high latency, and session drops caused by network behavior.
- Review SBC configs, SIP profiles, routing policies, media anchoring, session timers, NAT handling, header manipulation, and security policies.
- Investigate SIP ALG/helper behavior, double NAT, asymmetric routing, port exhaustion, MTU issues, and proxy interference.
- Validate QoS/DSCP, bandwidth policy, firewall pinholes, RTP port ranges, and geo/network path consistency.
- Work with customer network teams to collect:
- firewall configs
- NAT tables
- routing details
- packet captures
- SBC traces
- proxy behavior
- Drive debugging across customer LAN/WAN, internet edge, VPN, SBC, media relay, and PBX/carrier path.
- Recommend changes to SBC routing, keep-alive strategy, NAT traversal, RTP timeout, session-expires, TLS/SRTP interoperability, and resiliency design.
- Support multi-region / POP / edge architecture validation for real-time traffic.
- Provide customer-ready RCA and preventive recommendations.
Must-have skills
- 7+ years in enterprise voice network / SBC troubleshooting
- Strong hands-on expertise in:
- SBC platforms such as AudioCodes / Oracle / Ribbon / Cisco / similar
- SIP trunking
- Enterprise firewall/NAT behavior
- RTP media routing and anchoring
- QoS for voice/video traffic
- Strong networking fundamentals:
- TCP/IP
- UDP
- NAT/PAT
- DNS
- TLS
- MTU/MSS
- VPN
- routing
- proxies
- load balancers
- Ability to analyze:
- SBC logs/traces
- firewall captures
- routing asymmetry
- packet loss/jitter
- port and policy mismatches
- Good experience with Wireshark, tcpdump, sngrep, and vendor-specific trace tools
- Ability to talk directly with customer network/security teams
Preferred skills
- WebRTC-to-SIP interworking knowledge
- Experience with TURN/media relays/edge POP design
- Exposure to contact center or unified communications deployments
- Familiarity with cloud networking across AWS/Azure/GCP
- Experience with global rollouts and region-specific network issues
Customer-facing expectations
This person should be able to:
- lead technical workshops with network/security teams
- understand customer network topology quickly
- ask for the exact firewall, NAT, and routing artifacts needed
- explain why a problem is likely at SBC/network vs application/media layer
- recommend safe configuration changes and validation steps
- provide design best practices, not just incident-level fixes
Tools the engineer should be comfortable with
- Wireshark / tcpdump / sngrep
- SBC trace tools
- Firewall logs and policy review
- Routing and NAT table review
- QoS monitoring tools
- SIP ladder and packet correlation tools
- WAN performance / path analysis tools
Regards,
Aravindhan
