Kamailio and Freeswitch (VOIP) Developer

Job Description

We are looking for a skilled and passionate FreeSWITCH & Kamailio Developer to join our on-site team in Noida Extension. The ideal candidate will help us build a scalable, secure, and high-performance PBX platform tailored for enterprise-level VoIP deployments.

You will be responsible for designing, customizing, and maintaining cloud telephony systems, optimizing call flows, and handling SIP signaling at scale. This role is perfect for someone with deep technical knowledge of VoIP architecture and a hands-on approach to real-time communications.

Responsibilities

• Design and maintain scalable cloud telephony infrastructure
• Customize FreeSWITCH for audio/video conferencing (4000–5000 concurrent calls)
• Deploy FreeSWITCH behind load balancers for high availability
• Debug SIP signaling and analyze RTP/media streams (Wireshark, sngrep)
• Integrate codecs (PCMU, PCMA, G729, Opus) and support SDP offer/answer models
• Develop API-integrated PBX systems in coordination with frontend/backend teams
• Configure RTP Proxy and handle NAT traversal (TURN/STUN)
• Set up and manage SIP proxy servers (Kamailio/OpenSIPS)
• Work on SBCs to ensure secure and reliable call routing
• Bonus: Experience with WebRTC, SIPX, SMPP, and H.323

Required Skills

• Hands-on experience with FreeSWITCH, Asterisk, or similar VoIP platforms
• Strong knowledge of SIP, RTP, RTCP, NAT traversal, and TLS
• Experience in Kamailio/OpenSIPS configuration and routing logic
• Proficiency in Linux system administration and shell scripting
• Familiarity with tools like sngrep, tcpdump, and Wireshark
• Ability to debug and optimize VoIP call flows and media streams
• Excellent troubleshooting and problem-solving skills
• Bachelor's degree in Computer Science, IT, or related field
• Experience in telecom or VoIP support environment is a plus

Job Types: Full-time, Permanent

Pay: ₹13,650.56 - ₹100,000.00 per month

Benefits:

• Commuter assistance
• Flexible schedule

Ability to commute/relocate:

• Noida, Uttar Pradesh: Reliably commute or planning to relocate before starting work (Preferred)

Work Location: In person