Core Network Engineer

Job description

AST SpaceMobile and our global partners are building the first and only space-based cellular broadband network to be accessible by standard smartphones. Called SpaceMobile, this ultra-powerful network is being designed to provide connectivity at 4G/5G speeds everywhere on the planet – on land, at sea and in flight.

Job Summary:

We are seeking a highly skilled and motivated Senior Core Network Engineer with deep hands-on expertise in 3GPP wireless core networks (4G LTE and 5G NR). In this role, you will be responsible for the engineering, integration, configuration, and testing of our wireless core network elements and services. You will translate architectural designs into practical deployments, ensuring the network is robust, performant, and compliant with 3GPP standards. This is a critical role that requires a strong problem-solving mindset and a meticulous approach to network implementation.

Key Responsibilities:

Engineering & Implementation:

• 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.

Integration & Testing:

• 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).

Network Operations & Optimization:

• 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.

Documentation & Standards:

• 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.

Qualifications:

Education: Bachelor’s or master’s degree in electrical engineering, Computer Science, Telecommunications, or a related field.

Experience:

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

Technical Skills:

• 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.

Soft Skills:

• 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.

AST SpaceMobile is an Equal Opportunity, at will Employer; employment is governed on the basis of merit, competence and qualifications and will not be influenced in any manner by race, color, religion, gender, national origin/ethnicity, veteran status, disability status, age, sexual orientation, gender identity, marital status, mental or physical disability or any other legally protected status.