Analyze, design, implement, and verify the configuration and integration of subscriber data management nodes, networks, and systems across 2G through 5G infrastructure.
Own the subscriber data management platform across network generations.
Manage and operate HLR, HSS, UDR, and UDM nodes across 2G, 3G, 4G, and 5G core domains.
Design and maintain subscriber provisioning workflows, including IMSI/MSISDN management, service profiles, and roaming configurations.
Implement and verify MAP, Diameter (S6a, S6d, Cx, Sh, Zh), and HTTP/2-based (N8, Nudm) interfaces connecting subscriber data nodes to MSC, MME, AMF, SGSN, and other core elements.
Use and build dashboards to monitor subscriber node KPIs, surface abnormal conditions, and identify patterns before they become outages.
Own incident management for the subscriber data domain.
Perform maintenance, security audits, patching, and emergency response for HLR/HSS/UDM/UDR platforms.
Undertake fault handling and corrective actions at node, service, and infrastructure level.
Lead and contribute to project activities: E2E introduction of new subscriber management nodes.

At least 10 years of experience in core network engineering with a focus on subscriber data management in mobile networks.
BSc degree in Telecommunications, Computer Science, or equivalent; post-graduate studies are a plus.
10+ years of core telecommunications network experience, with a minimum of 5 years hands-on with HLR, HSS, UDR, or UDM platforms.
Deep operational knowledge of HLR platforms (e.g., Ericsson HLR, Nokia FlexiISN, Huawei HLR9820) and their MAP/TCAP/SCCP signaling stacks.
Hands-on experience with HSS platforms and Diameter-based interfaces: S6a, S6d, Cx, Sh, Zh — including Diameter routing agent (DRA) configuration and troubleshooting.
Practical experience with 5G UDM and UDR, including cloud-native deployments (containerized/Kubernetes-based NFs) and HTTP/2 SBI interfaces (N8, Nudm_SubscriberDataManagement, Nudr_DataRepository).
Solid understanding of subscriber profile structures: EPS subscription data, 5GS subscription, IMS subscription (Cx/Sh), CAMEL service data, and operator-determined barring.
Experience with IMSI/MSISDN range management, number portability (NP/MNP) integration, and SIM/eSIM provisioning workflows.

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HLR, HSS, UDM Architect

Key skills