Core Network Engineer

Summary

Join AST SpaceMobile and help build the first space-based cellular broadband network! As a Senior Core Network Engineer, you will engineer, integrate, configure, and test our wireless core network elements and services, translating architectural designs into practical deployments. You will ensure the network's robustness, performance, and 3GPP standard compliance. This critical role demands strong problem-solving and meticulous implementation skills. You will work with various technologies and platforms, including 4G LTE and 5G NR networks, virtualized and cloud-native functions, and automation tools. The position requires extensive experience in telecommunications and 3GPP core networks. Success in this role will contribute significantly to the launch and operation of a groundbreaking global network.

Requirements

• Bachelor's or master's degree in electrical engineering, Computer Science, Telecommunications, or a related field
• 10+ years of hands-on experience in telecommunications, with a strong focus on engineering, integrating, configuring, and testing 3GPP wireless core networks
• Proven experience with large-scale 4G LTE EPC and/or 5G SA Core deployments
• Extensive practical experience with core network elements from major vendors
• Demonstrated experience with virtualized and cloud-native network functions (VNF/CNF) deployment and lifecycle management on platforms like Kubernetes, OpenShift, OpenStack, or VMware
• Hands-on experience with wireless roaming configurations and inter-PLMN connectivity
• Deep practical knowledge of 3GPP standards for 4G (Release 8-15) and 5G (Release 15-18), specifically related to core network architecture, protocols, and call flows
• Strong expertise in core network protocols and interfaces (e.g., S1-AP, NAS, GTP-C/U, Diameter, HTTP/2, SCTP, PFCP)
• Proficiency in network security hardening and best practices for core network elements
• Solid scripting and automation skills (e.g., Python, Ansible, Terraform, Bash)
• Strong knowledge of IP networking, routing protocols (BGP, OSPF), and QoS mechanisms
• Experience with network monitoring and troubleshooting tools (e.g., Wireshark, packet sniffers, performance monitoring systems)
• Familiarity with public cloud environments (AWS, Azure, GCP) and cloud-native network principles
• Excellent problem-solving and analytical skills, with meticulous attention to detail
• Strong communication (written and verbal) and interpersonal skills
• Ability to work effectively in a fast-paced, collaborative team environment
• Self-motivated, proactive, and able to manage multiple priorities
• Ability to work independently and take ownership of tasks

Responsibilities

• Engineer, implement, and deploy 3GPP core network elements, including 4G LTE EPC (MME, SGW, DRA) and 5G SA Core (AMF, UPF, SMF, SEPP)
• Work closely with Solutions Architects to translate high-level designs into detailed engineering plans and configurations
• Configure core network elements, interfaces (e.g., S1-AP, NAS, GTP-C/U, Diameter, HTTP/2, SCTP, PFCP, N1-N15, etc.), and associated services
• Implement virtualized (VNFs) and cloud-native (CNFs) core network functions on various platforms (e.g., OpenStack, VMware, Kubernetes/OpenShift)
• Develop and implement network automation scripts and tools (e.g., Ansible, Python, Terraform) for configuration, deployment, and operational tasks
• Lead the integration of core network elements with other network domains (RAN, transport, OSS/BSS) and third-party solutions
• Design, develop, and execute comprehensive test plans (FAT, SIT, UAT) for core network features, performance, and stability
• Perform functional, performance, regression, and stress testing of core network components
• Identify, analyze, and troubleshoot complex technical issues, working closely with vendors and internal teams for resolution
• Support network trials and proof-of-concepts (PoCs)
• Provide expert-level support for operational issues, including incident resolution and root cause analysis
• Monitor core network performance, identify bottlenecks, and recommend optimization strategies
• Contribute to the continuous improvement of deployment, integration, and operational processes
• Create and maintain detailed engineering documentation, including configuration guides, MOPs (Method of Procedure), test reports, and as-built diagrams
• Ensure all implementations and configurations comply with 3GPP standards, internal guidelines, and security policies

Preferred Qualifications

Experience with Direct-to-Device (D2D) or Non-Terrestrial Networks (NTN) integration and testing is highly desirable