SIP/VoIP call performance testing experience with SIPp, Spectra, WinSIP, and StarTrinity
Automation experience using Python and Robot Framework
API test automation and performance testing experience with Locust, Blazemeter/Taurus, k6, Newman, and JMeter
GUI automation experience with TestCafe
CI/CD test integration experience
Basic Linux and Windows administration skills
Expertise in operating systems such as Linux (RHEL, CentOS, OEL) and Windows Servers/Workstations, along with DNS, DHCP, LDAP, and Active Directory servers
Experience in telecom applications such as Metaswitch Rhino, Dialogic Media Server, and Perimeta SBC, and telecom protocols such as SIP and RTP
Good knowledge of ITIL processes and security implementation/system hardening on telecom applications and services
SSCA SIP School Certified Associate, desirable
Knowledge of intelligent network service protocols such as INAP, CAP, and MAP, desirable
Experience using Metaswitch Scenario Simulator to produce test scenarios for SIP, INAP, and MAP protocols, desirable
Experience developing scripting, e.g. Python, desirable
Responsibilities
We design, scale, and maintain automated test frameworks for signaling, media handling, and regression suites
We build automation scripts to simulate high volumes of concurrent calls, load stress, and network degradation
We embed automated test scripts into continuous integration pipelines such as Jenkins, GitLab, and GitHub Actions
We author highly detailed test cases covering functional, negative, security, boundary, and edge‑case scenarios for multi-party call flows
We manage and structure test suites inside test management platforms such as Jira
We ensure full traceability between business requirements, technical specifications, and executed test cases
We capture and evaluate packet data using Wireshark and tcpdump to diagnose audio drops, call failures, or one‑way media
We verify SIP signaling, SDP negotiations, and RTP/SRTP media stream compliance
We continuously monitor and log critical VoIP KPIs including jitter, packet loss, latency, and Mean Opinion Score (MOS)
We generate comprehensive test execution summaries, metric dashboards, and formal test closure reports for stakeholders
We log clear, actionable bugs in Jira with SIP ladder diagrams, automated logs, and PCAP file captures
We partner closely with DevOps and Network Engineers to isolate, reproduce, and resolve complex infrastructure bugs
Technologies
API
Active Directory
CI/CD
DevOps
GitHub
GitLab
ITIL
JIRA
Jenkins
JMeter
LDAP
Linux
Network
Python
RHEL
Robot Framework
Security
Windows
More
We are seeking a highly skilled VoIP Services Tester with Automation Experience to join our engineering team on a 6-month hybrid assignment inside IR35, umbrella only. In this role, we ensure the reliability, quality, and security of our real-time voice and video communication systems across our global telecom infrastructure. We focus on exceptional voice quality and system stability, with opportunities to work closely with engineering, DevOps, and network teams.
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