Senior Principal Software Engineer – 5G Core Networks

Date Posted:

Location:

US-CA-SAN JOSE-826 ~ 200 Holger Way ~ BLDG 826

Contract Type:
Onsite

Security Clearance: TS/SCI with Polygraph (Active, existing required after day
1)

U.S. Citizenship: required (U.S. citizen)

Position:
Senior Principal Software Engineer – 5G Core Network protocol development

Employer:

Applied Signal Technology (AST), a subsidiary of Collins Aerospace, RTX.

Applied Signal Technology is a leader in strategic and tactical SIGINT solutions, providing high‑capacity broadband communications, signal processing, tactical SIGINT, and wireless communications solutions.

• Apply your 5G Core Network software development experience to advance our next generation mobile telecommunication processing solutions.
• Collaborate with technical leaders to further product visions and roadmaps and develop innovative software solutions.
• Collaborate with customers to elicit requirements and CONOPS, and perform technical research.
• Develop technical documentation, presentations, and/or lead concept demonstrations.
• Travel up to 15% to other AST sites and customer sites to support meetings and/or demonstrations and system deployments.

• Typically requires a degree in Science, Technology, Engineering or Mathematics (STEM) and a minimum of 10 years of prior relevant experience.
• Aggregate of 7 years software development experience in one or more of the following areas:
  Developing 3
  
  GPP network functions, network interfaces, and/or service-based interfaces, such as User Plane Function (UPF), Access and Mobility Management Function (AMF), Session Management Function (SMF), N4 and/or N11 network interfaces, Namf, Nsmf, and/or Nupf services.
• Developing protocols such as NAS, PFCP, GTP‑U, and/or HTTP/2.
• Reverse engineering telecommunications protocols.
• Troubleshooting distributed systems and control‑plane signaling paths.
• Using 5G core network control‑plane probes.
• Developing service‑based microservices with REST‑like APIs.
• Demonstrated expertise developing Linux‑based software systems utilizing modern C++, Python, or equivalent environments to architect, implement, and validate complex telecommunications processing solutions.
• Ability to obtain and maintain a U.S. government issued Top Secret SCI (TS/SCI) security clearance with polygraph after start.
• U.S. citizenship is required, as only U.S. citizens are eligible for a security clearance.

• Existing U.S. government issued TS/SCI security clearance with polygraph or current SSBI.
• Knowledge of AMF, SMF, UPF, UDM, PCF, AUSF, NRF behavior, interactions, and call flows.
• Experience developing 5G core network control‑plane probes for monitoring network traffic, extracting signaling and user‑plane information, decoding 3
  
  GPP protocols, and/or traffic replay.
• Experience with observability frameworks (Open Telemetry, Prometheus, Grafana).
• Familiarity with 4G EPC (MME, SGW, PGW, HSS).
• Familiarity with network virtualization and/or containerization technologies (KVM, VMware, Open Stack, AWS, Kubernetes, Helm, Docker).
• Experience developing with Go or Rust.

• Medical, dental, and vision insurance
• Three weeks of vacation for newly hired employees
• Generous 401(k) plan that includes employer matching funds and separate employer retirement contribution, including a Lifetime Income Strategy option
• Tuition reimbursement program
• Student Loan Repayment Program Life insurance and disability coverage
• Optional coverages you can buy pet insurance, home and auto insurance, additional life and accident insurance, critical illness insurance, group legal,  protection
• Birth, adoption, parental leave benefits
• Ovia Health, fertility, and family planning
• Adoption Assistance
• Autism Benefit
• Employee Assistance Plan, including up…