Telephony Engineer - VoIP/FreeSWITCH

Telephony Engineer (FreeSWITCH, VoIP) Max NP : 30 days Working Mode : In-Office Working Days : 5 Days Job Location : Gurugram Ideal Candidate : - 1. Strong FreeSWITCH Implementation Engineer profiles. - 2. Must have minimum 4+ years experience, with at least 3+ years of hands-on experience implementing, configuring, and supporting FreeSWITCH in production environments. - 3. Must have strong experience in designing and implementing FreeSWITCH call flows, including dialplans, IVRs, call routing, conferencing, SIP profiles, gateways, trunks, and extensions with end-to-end ownership. - 4. Must have strong hands-on knowledge of VoIP technologies, including SIP, RTP, RTCP, SDP, WebRTC , and should be capable of troubleshooting call drops, one-way audio, registration failures, NAT traversal, and SIP/RTP-related issues. - 5. Must have hands-on experience developing FreeSWITCH dialplans using XML and at least one scripting language such as Lua, JavaScript, or Python, including implementation of call queues, time-based routing, skill-based routing, and failover logic. - 6. Must have experience integrating FreeSWITCH with CRM/ERP systems, REST APIs, WebSockets, AI Voice Bots (ASR/TTS), or Billing Platforms, along with hands-on experience using Event Socket Library (ESL) for real-time call control. - 7. Must have strong Linux administration experience and should be comfortable deploying and managing FreeSWITCH on Ubuntu/CentOS, along with debugging using fs_cli, sngrep, tcpdump, and working with SQL (MySQL/PostgreSQL) for CDRs and reporting. - 8. Immediate Joiners or candidates who can join within 15 days will be highly preferred. - 9. Candidate must be currently based in Delhi NCR only . - 10. Experience with AWS, Azure, or GCP, High Availability (HA), Load Balancing, CI/CD pipelines, automation, backups, and scalable FreeSWITCH deployments. - 11. Experience implementing WebRTC-based calling solutions, including mod_verto, SIP over WSS, DTLS-SRTP, ICE, and OPUS codec configuration. Interview Process: HR Screening Machine assessment Virtual Interview with Tech Panel About Role: Key Skills: FreeSWITCH, VoIP, Linux, SQL, Cloud, WebRTC Roles & Responsibilities: We are looking for a FreeSWITCH Implementation Engineer who will be responsible for designing, deploying, configuring, integrating, and maintaining FreeSWITCH-based VoIP platforms. The role involves working closely with SIP, RTP, WebRTC, IVR, conferencing, call routing, and external integrations in a production environment. Key Responsibilities: FreeSWITCH Core Responsibilities: - Install, configure, and maintain FreeSWITCH in production environments from the scratch. - Design and implement call flows, dialplans, IVRs, conferencing, and call routing with complete ownership. - Configure SIP profiles (internal/external), gateways, trunks, and extensions. - Implement multi-tenant and high-availability FreeSWITCH architectures. SIP, RTP & Networking: - Strong understanding of SIP signaling, RTP media, and SDP negotiation. - Troubleshoot one-way audio, no-audio, call drops, registration failures. - Configure NAT traversal, firewall rules, and RTP port ranges. - Analyze SIP logs and traces (siptrace, sngrep, tcpdump). Dialplan & Scripting: - Develop dialplans using XML, Lua, JavaScript, or Python. - Implement logic for call queues for inbound and outbound calls, time-based routing, skill-based routing, and failover and fallback handling. Integrations & APIs: - Integrate FreeSWITCH with CRM/ERP systems, billing platforms, AI voice bots (ASR/TTS), and external WebSocket or REST services. - Use Event Socket Library (ESL) for inbound and outbound ESL, and real-time call control and monitoring. WebRTC & Media: - Configure WebRTC support (DTLS-SRTP, ICE, OPUS). - Work with mod_verto and SIP over WSS. - Implement browser-based calling solutions. Monitoring & Debugging: - Monitor system performance and call quality. - Analyze logs and CDRs. - Optimize codec usage and RTP performance. - Handle live production incidents and RCA. Deployment & Operations: - Deploy FreeSWITCH on Linux (CentOS/Ubuntu) and cloud platforms (AWS/GCP/Azure). - Configure HA, load balancing, and scaling. - Work with DevOps teams for CI/CD, backups, and automation.