Sr. VoLTE/IMS Test Engineer - 5G/LTE Core Networks-Onsite

Cognizant is looking for a test lead engineer that has 6-8 years experience SIP, IMS Core, VoLTE/CVoIP call flow process for testing and validation. Following skills/experience required: Requirements Strong knowledge in 5G/LTE/UMTS VoLTE/IMS Network Performance and Capacity Test and IMS Nodes Performance Benchmarking Activities Extensive hands‑on experience with VoLTE/IMS Call Processing and VoLTE/IMS Supplementary Services Hands‑on experience with IMS related protocols and signaling analysis (VoLTE/IMS, VOIP Call Flows (SIP/SDP/H.248 etc.) using Iris Analyzer and RADCOM) Working experience on IMS interworking entities (BGCF, MGCF, MRFC, MRFP, AGW, IBCF, TrGW) and interfaces Expertise in SIP based call flows for VOIP/IMS, Voice and Supplementary Services Experience with LTE core system interfaces and protocols such as S1-MME, S1-U, S6a, S11, S5/S8, Rx, NAS, S1-AP, RRC, GTPv2c, GTP-U, SGs-AP, Gn, Gx, Ga, Sy In‑depth understanding of telecom protocols and technologies such as GTPV2, SIP, RTP, IPv4 and IPv6, DIAMETER, DNS, H.248, IPSec, TCP-IP, LDAP, etc. Design & troubleshooting experience in VoLTE E2E Call Flows and RCA debugging skills, and IP network design, planning and optimization Scripting experience in any language such as Python, Unix, Selenium and hands‑on experience on Android adb command for automation and taking device logs Tool experience with Wireshark, QXDM, RADCOM, IXIA, EXPO, LANDSLIDE, etc. *Please note, this role is not able to offer visa transfer or sponsorship now or in the future* Applications will be accepted until June 4th, 2026

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Compensation & Benefits $84,000 – $117,000 per year Bonus plus comprehensive benefits Additional Information Onsite role Visa sponsorship is not available now or in the future. Candidates requiring sponsorship will not be considered. Benefits Medical/Dental/Vision/Life Insurance Paid holidays plus Paid Time Off 401(k) plan and contributions Long-term/Short-term Disability Paid Parental Leave Employee Stock Purchase Plan #J-18808-Ljbffr Cognizant