IMS Core Engineer

OXIO; United States; On-site; USD 140,000 - 190,000; Full time

Job summary

OXIO is seeking an IMS Core Engineer/Architect to analyze, configure, and verify integration of IMS/VoLTE nodes within 2.5G/3G/4G networks. You will manage IMS domains, optimize call flows, and perform security audits while supporting 7x24 monitoring as needed.

Minimum 10 years in core telecom networks with strong SIP/Diameter expertise and Linux/Wireshark proficiency. Fluency in English required; on-site work in a fast-paced environment.

Qualifications

• At least 10 years’ experience in the core network domain with a mobile networks.
• Working knowledge of telecom networks like 2G, 2.5G, 3G and LTE (MME, SGW, PGW, and MME).
• Great Conceptual understanding of IMS evolution and trends - IMS Subsystems, functionalities and IMS services call flows.

Responsibilities

• Manage networks and nodes within the IMS domain for 2.5G, 3G & 4G networks (SIP, H323, IMS/IMT, VoLTE, VoWiFi).
• Using dashboards (and building new ones) to clearly and quickly discover issues and patterns.
• Follow communications procedures when handling incidents with internal and external stakeholders.
• Maintenance, troubleshooting, security audits, and emergency response.
• Fault handling and corrective actions on node, service and infrastructure level.
• Handle project activities, implementing/adapting IMS E2E service functionalities, nodes, services.
• Cover 7x24 monitoring shift responsibilities when needed.
• Wireshark tracing to debug issues and providing input for improvements.

Skills

IMS core networks

VoLTE/VoWiFi

SIP/Diameter

Troubleshooting

On-call support

Linux shell

Documentation

2G/3G/LTE knowledge

Education

BSc in Telecommunication or Computer Science

Tools

Wireshark

Sniffers

Linux

Job description

IMS Core Engineer / Architect

The IMS/VoLTE Integration Engineer will analyze, prepare, implement and verify the configuration and integration of a node, network and/or system. Your scope of work could include the scenarios of introduction, upgrade expansion, functionality and capacity. Your work will in part form our customer legacy.

Key Responsibilities

• Manage networks and nodes within the IMS domain for our 2.5G, 3G & 4G networks (SIP, H323, IMS/IMT, VoLTE, VoWiFi)
• Using dashboards (and building new ones) to clearly and quickly discover issues and patterns
• Accountable and responsible to follow the communications procedures in place when handling an incident. Communication is both internal within our company and external to our third-party providers.
• Maintenance, troubleshooting, security audits, and emergency response
• Undertake fault handling and corrective actions on node, service and infrastructure level
• Handle project activities, implementing / adapting (new) IMS E2E service functionalities, nodes, services
• When needed, cover the 7x24 monitoring shift responsibilities (On call support, Baby Sitting activities etc.)
• Wireshark tracing of critical infrastructure to debug issues
• Provide input, implement and verify improvements in processes and work instructions
• Verify and implement configuration changes
• Work to identify and drive improvement

Key Qualifications

At least 10 years’ experience in the core network domain with a mobile networks

• Holding a BSc degree in Telecommunication or Computer Science (post-graduate studies are a bonus) and 10+ years core telecommunications network experience.
• Working knowledge of telecom networks like 2G, 2.5G, 3G and LTE (MME, SGW, PGW, and MME).
• Great Conceptual understanding of IMS evolution and trends - IMS Subsystems, functionalities and IMS services call flows.
• Great knowledge of IMS network topology (their various interfaces), Core IMS Parameters and Features.
• Worked on different type of Core Nodes, CSFB, IMS (P-CSCF, I-CSCF, S-CSCF, MTAS, HSS, CUDB, MGCF, etc.).
• Experience with SS7, ISUP, BICC, SIP, H248, Diameter signaling & protocols configuration change IMS based services is necessary.
• Operation and maintenance of IMS platforms for Alarms, faults/abnormal conditions handling, Analysis of traces, High troubleshooting skills, system backup/restore from backup files, Fault Diagnostics, Preventive Maintenance & upgrades of IMS nodes.
• Configuration preparation & implementation for configuration changes requests for IMS nodes and Integration for all nodes (S-CSCF, I-CSCF, MTAS, HSS, CUDB, etc.) as well.
• Hands on with sniffers, Wireshark and testing tools in advanced mode.
• Hands on with Linux/Unix based systems (you can find your way around a linux shell).
• Understanding of 3GPP, ITU-T and ANSI standards.
• Understanding of roaming agreements and IR.21, including IREG testing.
• VoLTE Troubleshooting and call trace analysis.
• Strong writing and documentation skills are needed to develop reports.
• Adaptability and responding to change.
• Be able to work under pressure.
• You are fluent in English (written and spoken).
• Ready to work on morning/afternoon shifts.
• Good interaction with external customers and internal teams.

Nice to have

• 2+ years scripting experience (Python, Bash, etc.)

OXIO is committed to fostering a diverse, equitable, and inclusive workplace where all employees feel valued and empowered. We believe that diversity in all its forms drives innovation and creativity, and we strive to create an environment that reflects and celebrates the unique backgrounds, perspectives, and talents of our employees. We do not discriminate against any employee or applicant for employment based on race, color, religion, sex (including pregnancy, gender identity, and sexual orientation), national origin, age, disability, genetic information, veteran status, or any other characteristic protected by applicable federal, state, or local law. We are dedicated to providing a work environment free from discrimination and harassment. We committed to ensuring that all qualified applicants have an equal opportunity to apply for job openings. If you need assistance or an accommodation due to a disability, please contact us at [e-mail] for more information.