Core Network and IP Engineer (MVNO) at Lebara Nigeria

Position Overview

• The Core Network and IP Engineer will be responsible for the design, deployment, integration, and operations of the MVNO core network and IP infrastructure. This role ensures seamless interoperability between the MVNO Core, OSS/BSS platforms, and the host MNO networks while maintaining high availability, scalability, and security of services.

Key Responsibilities

Core Network Responsibilities

• Design, deploy, and operate MVNO Core Network elements, including:
  • HSS/HLR
  • PCRF/PCF
  • IMS (CSCF, SBC, MGW, TAS, MMTel)
  • EPC/5GC elements (MME, SGW, PGW, UPF, AMF, SMF, UDM, AUSF)
• Integrate with host MNO’s RAN and interconnect with roaming partners.
• Perform interoperability testing (IOT) with multiple MNOs (2G/3G/4G/5G NSA/SA).
• Ensure QoS, policy enforcement, lawful interception, and number portability.
• Support VoLTE, VoWiFi, and traditional CS fallback services.
• Manage signaling protocols: Diameter, SIP, SS7, MAP, CAMEL, GTP, SCTP, etc.

IP Network Responsibilities

• Design, deploy, and maintain IP/MPLS backbone and transport infrastructure for MVNO services.
• Configure and optimize routing (BGP, OSPF, IS-IS) and switching.
• Manage IP address plans, NAT, CG-NAT, and DNS/DHCP platforms.
• Ensure IP capacity planning, redundancy, and resiliency.
• Implement and manage IP interconnects (peering, transit, IXP).
• Integrate IP/MPLS transport with MVNO Core and Data Centers.

Security & Compliance

• Deploy and manage firewalls, SBC, DDoS protection, and IPS/IDS systems.
• Enforce IPsec/MPLS VPNs for secure MNO interconnection.
• Support regulatory compliance: lawful interception, emergency calling, data retention.
• Work closely with the IP & Security team to safeguard signaling and IP networks.

Operations & Support

• Provide 2nd/3rd line support for Core and IP issues.
• Troubleshoot network performance, call flows, and subscriber experience issues.
• Participate in change management and release planning.
• Maintain documentation (HLD, LLD, SOPs, configurations, as-built).
• Train and support NOC teams for monitoring and fault management.

Required Skills & Experience

• Bachelor’s degree in Telecommunications, Computer Science, or related field.
• 5–8 years of experience in Core Network engineering in MNO/MVNO/MVNE environments.
• Hands-on experience with EPC/5GC, IMS, HSS, PCRF, MGW, SBC.
• Strong knowledge of IP networking: IPv4/IPv6, MPLS, VPNs, BGP, OSPF, QoS.
• Proficiency in signaling: SIP, Diameter, SS7, CAMEL, GTP, SCTP.
• Experience with VoLTE/VoWiFi, 5G SA/NSA, and roaming platforms.
• Vendor experience (Ericsson, Nokia, Huawei, ZTE, Cisco, Juniper, Mavenir, Affirmed, Open5GS, etc.).
• Familiarity with virtualization/cloud platforms (VMware, OpenStack, Kubernetes).
• Strong troubleshooting and packet analysis (Wireshark, tcpdump).

Key Competencies

• Analytical problem-solving and root cause analysis.
• Ability to work in multi-vendor, multi-MNO environments.
• Strong communication for cross-functional coordination with OSS/BSS, IT, and regulatory teams.
• Documentation and technical writing skills.
• Flexibility to work in 24x7 operations environment when required.