LTE 5G Tester

Reqroute, Inc; Warrenville (IL); On-site; USD 85,000 - 115,000; Full time

Job summary

Reqroute, Inc in Warrenville, IL is seeking an experienced Test Engineer with strong expertise in IMS Core, SIP, and VoLTE/CVoIP call flows. The ideal candidate should have 6–8 years of hands-on experience in validating and troubleshooting IMS/VoLTE networks, analyzing signaling protocols, and performing end-to-end call flow testing.

This position requires onsite presence, and candidates with strong telecom testing and IMS/VoLTE troubleshooting experience will be given preference.

Qualifications

• 6–8 years of experience in Telecom Testing, IMS Core, SIP, and VoLTE/CVoIP environments.
• Strong knowledge of 5G, LTE, and UMTS technologies.
• Hands-on experience with VoLTE/IMS Call Processing and Supplementary Services.

Responsibilities

• Validate and troubleshoot IMS/VoLTE networks.
• Analyze signaling protocols and perform end-to-end call flow testing.
• Conduct root cause analysis (RCA) for VoLTE call flows.

Skills

Telecom Testing

IMS Core

SIP

VoLTE/CVoIP

5G

LTE

Scripting (Python, Unix Shell, Selenium)

Tools

Wireshark

QXDM

RADCOM

IXIA

EXPO

LANDSLIDE

Iris Analyzer

Job description

Job Summary

We are seeking an experienced Test Engineer with strong expertise in IMS Core, SIP, VoLTE/CVoIP call flows, and telecom network testing. The ideal candidate will have 6–8 years of hands‑on experience in validating and troubleshooting IMS/VoLTE networks, analyzing signaling protocols, and performing end‑to‑end call flow testing in LTE and 5G environments.

Required Skills & Experience

• 6–8 years of experience in Telecom Testing, IMS Core, SIP, and VoLTE/CVoIP environments.
• Strong knowledge of 5G, LTE, and UMTS technologies.
• Hands‑on experience with VoLTE/IMS Call Processing and Supplementary Services.
• Expertise in VoLTE/IMS Network Performance & Capacity Testing and IMS Node Benchmarking.
• Strong understanding of SIP‑based VoIP/IMS Call Flows, including Voice and Supplementary Services.
• Experience analyzing signaling protocols using Iris Analyzer and RADCOM.
• Hands‑on experience with IMS interworking entities such as:
• BGCF, MGCF, MRFC, MRFP, AGW, IBCF, TrGW
• Experience with LTE Core interfaces and protocols including:
• S1-MME, S1-U, S6a, S11, S5/S8, Rx, NAS, S1-AP, RRC
• GTPv2-C, GTP-U, SGs-AP, Gn, Gx, Ga, Sy

In‑depth knowledge of Telecom protocols and technologies

• SIP, RTP, Diameter, DNS, H.248, IPSec, TCP/IP, LDAP, IPv4 / IPv6
• GTPv2

Strong troubleshooting and Root Cause Analysis (RCA) skills for VoLTE end‑to‑end call flows.

• Experience with IP network design, planning, and optimization.
• Scripting experience using Python, Unix Shell, Selenium, or similar technologies.
• Hands‑on experience with Android ADB commands for automation and device log collection.

Tools Experience

Experience with one or more of the following tools:

• Wireshark, QXDM, RADCOM, IXIA, EXPO, LANDSLIDE
• Iris Analyzer

Top 3 Required Skills

• IMS / VoLTE Call Flow Analysis and Testing
• Telecom Protocols (SIP, RTP, Diameter, GTPv2, H.248, DNS, TCP/IP, IPv4/IPv6)
• IMS Interworking Entities (BGCF, MGCF, MRFC, MRFP, AGW, IBCF, TrGW) and Related Interfaces

Note: This position requires onsite presence in Warrenville, IL. Candidates with strong telecom testing and IMS/VoLTE troubleshooting experience will be given preference.