Principal 4G/5G Core Engineer

About the role

We are seeking an experienced Principal Core Engineer with deep expertise in 4G/5G Core networks to support both the deployment and long-term operation of cloud-based Core infrastructure at Iridium.

Responsibilities

• Assist with the completion of greenfield deployment of multiple Mavenir Cores to the cloud
• Lead integration efforts and maintain connections with MNO Partners and Syniverse
• Provide escalation support for Mavenir 4G EPC and 5G Core network functions (AMF, SMF, UPF, PCF, NRF, IMS, SBC)
• Define, then monitor, and later evolve our ability to maintain Core network health
• Provide advanced troubleshooting across: SIP, Diameter, GTP, HTTP/2, PFCP signaling, VoLTE/VoNR call flows, Data session establishment failures
• Lead Major Incident Management (MIM) calls for high-severity core outages
• Conduct deep Root Cause Analysis (RCA) using logs, traces, KPIs, and probe captures
• Correlate alarms and performance metrics to prevent false positives and reduce MTTR
• Perform cloud-native core deployments in Kubernetes and AWS-based environments
• Lead collaboration activities with RAN, Transport, and Cloud teams to resolve cross-domain issues
• Validate software upgrades, patches, and configuration changes in production
• Create and maintain SOPs, runbooks, and troubleshooting documentation
• Mentor junior engineers and provide technical training on Core network troubleshooting
• Ensure SLA/KPI compliance for availability, call success rates, and session setup times
• Participate in 24x7 on-call rotation and major incident bridge support

Requirements

• Bachelor’s degree in Telecommunications, Computer Science, Engineering, or related field; post-graduate degree preferred
• 10+ years of experience in telecom Core network operations
• Extensive, practical experience with a 4G/5G Core
• Deep understanding of: 4G/5G Core architecture (EPC & 5GC SBA architecture), IMS core and VoLTE/VoNR call flows, Diameter, SIP, GTPv2, PFCP, HTTP/2
• Experience working in a cloud-native/Kubernetes environment
• Strong Linux command-line troubleshooting skills
• Familiarity with Kafka feeds and performance monitoring integrations
• Ability to perform structured RCA and document findings clearly
• Strong communication skills, with the ability to lead technical bridges and confidently present products, deliverables, analyses, and/or issues

Qualifications

• Knowledge of 3GPP practices and requirements
• AWS certification (i.e., AWS Certified Cloud Practitioner, AWS Certified Advanced Networking, AWS Certified AI Practitioner, etc).
• Kubernetes certification (CKA/CKAD)
• Experience operating 4G Core networks (Mavenir is a plus)
• Experience operating 4G Ground RAN networks (Gatehouse is a plus)
• Good understanding or working knowledge of monitoring IOT device links
• Basic understanding or working knowledge of Non-Terrestrial Network (NTN) technologies
• Basic understanding or working knowledge of satellite-to-cell integration and 4/5G NTN architecture
• Hands-on experience with Grafana dashboard development and alarm correlation
• Understanding of CI/CD pipelines for telecom cloud deployments
• Technical industry certification in Network+ or Linux (RedHat, CentOS, etc.)
• Experience with Core Cloud operations and best practices is highly desirable