We are looking for a skilled SIP Performance and Validation Engineer to join our team responsible for ensuring the reliability, scalability, and high performance of our SIP-based communication platforms. You will lead performance testing using Spirent Landslide and SIPp, while performing in-depth analysis to identify bottlenecks and drive optimization recommendations.
What we are looking for in the candidate:
- Performance-driven engineer who loves pushing systems to the limit.
- Strong analytical mindset with excellent problem-solving skills.
- Ability to clearly communicate technical findings and recommendations.
- Self-motivated and detail-oriented.
Key Responsibilities:
- Design, develop, and execute comprehensive SIP performance and scalability test plans using Spirent Landslide and SIP to simulate high-volume call traffic, registration storms, and complex signaling scenarios.
- Create and maintain custom SIPp scenarios (XML) for various test cases including basic calls, INVITE floods, REGISTER storms, SUBSCRIBE/NOTIFY, and failure scenarios.
- Exercise and validate the SIP stack under load, measuring key metrics such as CPS (Calls Per Second), concurrent sessions, latency, packet loss, and error rates.
- Perform deep-dive network and protocol analysis using tcpdump, Wireshark, and other packet capture tools.
- Identify performance bottlenecks in SIP infrastructure components and provide clear, data-driven recommendations for optimization.
- Develop automation scripts using Python and Bash to orchestrate testing, parse results, generate reports, and integrate with CI/CD pipelines.
- Build and maintain automated test frameworks for repeatable performance validation.
- Document test results, create detailed performance reports, and present findings to technical and leadership audiences.
- Support production troubleshooting by analyzing live traffic captures.
Required Qualification:
- Strong Networking Background: Deep understanding of IP networking, TCP/IP, UDP, and advanced troubleshooting.
- Expert-level tcpdump / Wireshark analysis skills — must be able to efficiently analyze complex SIP/SDP/RTP traces.
- Hands-on experience with Spirent Landslide for SIP/RTP performance testing.
- Strong experience with SIPp — creating custom scenarios, running high-scale load tests, and interpreting results.
- Proficient in Python and Bash scripting for test automation, data parsing, and performance reporting.
- Solid experience with SIP protocol in depth.Strong Linux administration and performance tuning skills.
Recommended Experience:
- Freeswitch — configuration, performance tuning, and troubleshooting.
- Kamailio (or OpenSIPS) — routing logic, performance optimization, and scaling.
- Experience with high-availability SIP deployments in production environments.
- Advanced scripting and automation (Python preferred).
- Familiarity with media handling (RTP, RTCP, SRTP, codecs, transcoding).
Nice to have:
- Experience with other SIP platforms (Asterisk, etc.).
- Knowledge of WebRTC, IMS, or 5G signaling.
- Cloud-native experience (Kubernetes, Docker).
- Background in database performance tuning (especially PostgreSQL/MySQL in VoIP context).