Job Opening: FreeSWITCH Developer

Location: Ecospace Business Park, Rajarhat, Newtown, Kolkata

Employment Type: Full time, Permanent

Shift: Day Shift

Experience: Minimum 4+ years in FreeSWITCH/VoIP Development

Responsibilities:

- Design, develop, deploy, troubleshoot, and maintain tools and services supporting our cloud telephony network.
- Customize FreeSWITCH for large-scale audio/video conferencing (1000–1500 concurrent calls).
- Expertise in SIP, RTP, RTCP, TURN, STUN, NAT, TLS.
- Hands-on experience with RTP Proxy and routed audio conferences.
- Understanding of SDP Protocol offer/answer mechanism.
- Work with load testing tools for FreeSWITCH audio conferences.
- Deploy and manage multiple FreeSWITCH instances using load balancers.
- Debug issues using packet captures (Wireshark/Ngrep).
- Collaborate with mobile/API teams for integration and support.
- Knowledge of codecs (PCMU, PCMA, G729, Opus) and open-source telephony technologies (FreeSWITCH, WebRTC).
- Familiarity with SIP servers (SER/OpenSER),



proxy servers, SBC, SIPX is a plus.

Qualifications:

- Bachelor’s degree in Engineering (B.Tech/MCA).
- 4+ years of hands-on experience in FreeSWITCH development or related VoIP technologies.
- Strong knowledge of Linux environments and command-line tools.
- Basic to intermediate SQL knowledge.
- Proficiency in scripting (Bash, Python, Perl) for automation.
- Strong understanding of VoIP protocols (SIP, RTP), networking principles (TCP/IP, DNS, DHCP, routing protocols).
- Excellent troubleshooting skills with ability to resolve complex technical issues.
- Strong problem-solving, communication, and collaboration skills.

Industry Preference:

- Travel (Preferred)
- Any Industry (Required)

Skills:- FreeSWITCH, VoIP Protols, Audioconferencing, Videoconferencing, RTP proxy, Linux/Unix, Scripting, Audio codecs and WebRTC

📌 Freeswitch Developer (Kolkata)
🏢 Monjura Parveen
📍 Kolkata