Senior IMS Test Engineer
Location: Hatfield, Hyrbid 3x a week on site.
Technical Expertise & Capability Summary
IMS Core Network Expertise
* Strong working knowledge of IMS architecture and core network elements including CSCF, MTAS, SBG, BGF, IPSMGW, AFG, HPSYNC Server and SDIN
* Experience supporting and validating core network functionality within complex telecom environments
VoLTE / VoNR / VoWiFi Testing
* Proven expertise in VoLTE, VoNR and VoWiFi validation
* Strong understanding of 5G call flows, including registration, session management and handover procedures
* Experience validating voice services across LTE and 5G networks
Protocol & Interface Knowledge
* Solid understanding of SIP, SDP, MGCP, Diameter, RTP/RTCP and GTP protocols
* Experience working with Diameter interfaces including Cx, Dx, Ro and Rf
* Ability to analyse signalling flows and troubleshoot protocol-level issues
3GPP Standards & Compliance
* Good understanding of 3GPP specifications for LTE and 5G networks
* Experience ensuring solutions align with industry standards and compliance requirements
End-to-End (E2E) Testing
* Hands-on experience performing end-to-end testing across full call lifecycle scenarios
* Validation of registration, call setup, hold, resume, call waiting and conference call functionality
* Strong focus on service validation and customer-impact prevention
Nice to haves:
* RAN (Radio Access Network) knowledge
Senior IMS Test Engineer
Location: Hatfield, Hyrbid 3x a week on site.
Technical Expertise & Capability Summary
IMS Core Network Expertise
* Strong working knowledge of IMS architecture and core network elements including CSCF, MTAS, SBG, BGF, IPSMGW, AFG, HPSYNC Server and SDIN
* Experience supporting and validating core network functionality within complex telecom environments
VoLTE / VoNR / VoWiFi Testing
* Proven expertise in VoLTE, VoNR and VoWiFi validation
* Strong understanding of 5G call flows, including registration, session management and handover procedures
* Experience validating voice services across LTE and 5G networks
Protocol & Interface Knowledge
* Solid understanding of SIP, SDP, MGCP, Diameter, RTP/RTCP and GTP protocols
* Experience working with Diameter interfaces including Cx, Dx, Ro and Rf
* Ability to analyse signalling flows and troubleshoot protocol-level issues
3GPP Standards & Compliance
* Good understanding of 3GPP specifications for LTE and 5G networks
* Experience ensuring solutions align with industry standards and compliance requirements
End-to-End (E2E) Testing
* Hands-on experience performing end-to-end testing across full call lifecycle scenarios
* Validation of registration, call setup, hold, resume, call waiting and conference call functionality
* Strong focus on service validation and customer-impact prevention
Nice to haves:
* RAN (Radio Access Network) knowledge