6 months
Hybrid
Inside IR35 - umbrella only
We are seeking a highly skilled VoIP Services Tester with Automation Experience to join our engineering team. In this role, you will ensure the reliability, quality, and security of our real-time voice and video communication systems. You will lead the design of automated testing frameworks, author rigorous technical test cases, and produce comprehensive test reports that drive our deployment decisions.
The ideal candidate bridges the gap between deep network protocol analysis and modern software automation, ensuring exceptional voice quality and system stability across our global telecom infrastructure.
As part of this role, you are required to do the following
1. Test Automation & Framework Development
Design Automation: Develop, scale, and maintain automated test frameworks for signaling, media handling, and regression suites.
Simulate Load: Build automation scripts to simulate high volumes of concurrent calls, load stress, and network degradation.
CI/CD Integration: Embed automated test scripts into continuous integration pipelines (e.g., Jenkins, GitLab, GitHub Actions).2. Test Documentation & Case Design
Design Test Cases: Author highly detailed test cases covering functional, negative, security, boundary, and edge-case scenarios for multi-party call flows.
Test Case Repository: Manage and structure test suites inside test management platforms (e.g., Jira).
Track Traceability: Ensure full traceability between business requirements, technical specifications, and executed test cases.3. Protocol Validation & Network Diagnostics
Analyze Traffic: Capture and evaluate packet data using Wireshark and tcpdump to diagnose audio drops, call failures, or one-way media.
Validate Protocols: Verify SIP signaling, SDP negotiations, and RTP/SRTP media stream compliance.
Assess Quality Metrics: Continuously monitor and log critical VoIP KPIs including jitter, packet loss, latency, and Mean Opinion Score (MOS).4. Test Reporting & Defect Management
Publish Test Reports: Generate comprehensive test execution summaries, metric dashboards, and formal test closure reports for stakeholders.
Document Defects: Log clear, actionable bugs in Jira accompanied by SIP ladder diagrams, automated logs, and PCAP file captures.
Collaborate on Fixes: Partner closely with DevOps and Network Engineers to isolate, reproduce, and resolve complex infrastructure bugs.Essential
SIP/VoIP call performance testing with SIPp, Spectra, WinSIP, StarTrinity
Automation using Python & Robot Framework
API Test Automation & performance testing with Locust, Blazemeter/Taurus, k6, newman, jmeter
GUI Automation with TestCafe
CI/CD Test Integration
Linux & Windows basic administration skills
Expertise in Operating Systems like Linux ( RHEL, CentOS , OEL) , Windows Servers/Workstations along with Servers DNS/DHCP/LDAP/A.D
Experience in Telecom Applications ( Metaswich Rhino, Dialogic Media Server, Perimeta SBC ) and Telecom Protocols ( SIP, RTP )
Have good Knowledge in ITIL Process and Security implementation/System hardening on Telecom Applications and ServicesDesirable
SSCA SIP School Certified Associate
Knowledge in Intelligent Network service protocols like INAP, CAP, MAP
Experience in using Metaswitch Scenario Simulator for producing test scenarios for SIP, INAP, MAP protocols etc.
Experience in developing scripting, e.g. PythonIf you receive suspicious outreach claiming to be from us, please contact us via the ManpowerGroup website
Salary description
£300.00 - £370.00 per day