5GC – IMS Voice & Messaging QA Engineer | Tanint Recruitment | Düsseldorf, Germany

Job Title: 5GC – IMS Voice & Messaging QA Engineer | Tanint Recruitment | Düsseldorf, Germany
Recruiting Company: Tanint Recruitment
Job Location: Düsseldorf, Germany
Job Type: 3‑Month Extendable Contract (On‑site)
Application Method: Send CV to
Contact:
🛡️ Industry: 5G Core / IMS / Telecom QA Engineering

Position Summary

This role focuses on validating and ensuring the quality of IMS Voice and Messaging services within a 5G Core environment. As a QA Engineer, you will execute end‑to‑end testing, analyze IMS call flows, and verify service behavior across complex telecom architectures. Your contributions will directly support successful deployment, stability, and optimization of IMS solutions.

Detailed Job Description

As the 5GC – IMS Voice & Messaging QA Engineer, you will join a high‑performance team responsible for validating IMS‑based services—particularly VoLTE/VoNR voice and SMS functionalities. Working hands‑on with Mavenir IMS platforms, you will perform detailed test planning, execution, troubleshooting, and defect analysis across 5GC and IMS layers. You will collaborate with engineering, integration, and vendor teams to ensure accurate call‑flow behavior, service continuity, and compliance with operator requirements. This role is ideal for a telecom QA expert with strong IMS understanding and hands‑on lab or live‑network testing experience.

✅ Key Responsibilities

• Perform functional, regression, and integration testing for IMS Voice & Messaging services.
• Validate IMS call flows, SIP signaling, and 5GC interactions using tracing tools.
• Execute test cases for VoLTE/VoNR, SMS over IMS, supplementary services, and emergency call flows.
• Work with Mavenir IMS components during deployment and testing phases.
• Document defects, analyze logs, and support troubleshooting with engineering teams.
• Ensure service stability, call quality, and adherence to operator requirements.
• Coordinate with multiple technical teams across QA, integration, and vendor sides.

Required Qualifications & Skills

• Strong hands‑on experience in IMS deployment and testing, ideally with Mavenir IMS.
• Solid understanding of IMS call flows for Voice, SMS, registration, and session management.
• Experience testing VoLTE/VoNR, SMS over IMS, and SIP/DIAMETER protocol analysis.
• Familiarity with 5G Core functions (AMF, SMF, UPF) and their interaction with IMS.
• Proficiency using tools such as Wireshark, SIP analyzers, trace collectors, and log parsers.
• Background in telecom QA, feature validation, or service verification.

✨ Nice-to-Have Skills

• Experience working with European telecom operators.
• Understanding of SBC, TAS, PCRF/PCF, and supplementary service flows.
• Knowledge of automation frameworks for telecom QA.
• Exposure to interworking testing (IMS ↔ CS fallback or messaging interconnect).

Recruitment Pro Tip

Showcase projects where you validated IMS call flows or worked with Mavenir IMS—especially examples involving VoLTE/VoNR or SMS over IMS. Clear evidence of SIP expertise and hands‑on troubleshooting will make your application stand out immediately.