Job Description:

Why should you choose us?

Rakuten Symphony is reimagining telecom, changing supply chain norms and disrupting outmoded thinking that threatens the industry’s pursuit of rapid innovation and growth. Based on proven modern infrastructure practices, its open interface platforms make it possible to launch and operate advanced mobile services in a fraction of the time and cost of conventional approaches, with no compromise to network quality or security.

Rakuten Symphony has operations in Japan, the United States, Singapore, India, South Korea, Europe, and the Middle East Africa region. For more information, visit: https://symphony.rakuten.com

Building on the technology Rakuten used to launch Japan’s newest mobile network, we are taking our mobile offering global.

To support our ambitions to provide an innovative cloud-native telco platform for our customers, Rakuten Symphony is looking to recruit and develop top talent from around the globe. We are looking for individuals to join our team across all functional areas of our business – from sales to engineering, support functions to product development.

Let’s build the future of mobile telecommunications together!

About Rakuten Group, Inc. (TSE: 4755) is a global leader in internet services that empower individuals, communities, businesses and society. Founded in Tokyo in 1997 as an online marketplace, Rakuten has expanded to offer services in e-commerce, fintech, digital content and communications to 2 billion members around the world. The Rakuten Group has over 30,000 employees, and operations in 30 countries and regions. For more information visit https://global.rakuten.com/corp/.

Role Summary:

We are looking for an experienced SDM & 5G Core Operations Specialist to join our global engineering team. In this role, you will be the subject matter expert for subscriber data, authentication, and identity management. You will bridge the gap between traditional HLR/HSS environments and the modern 5G Cloud-Native Core, ensuring 99% availability for our global subscribers using Shared Data Layer (SDL) architecture.

Key Responsibilities:

• SDM Lifecycle Management: Lead the operations, troubleshooting, and optimization of subscriber data platforms, including HLR/HSS (Legacy) and UDM/UDR (5G).
• Shared Data Layer (SDL) Architecture: Manage and maintain the SDL to decouple subscriber state from network functions, enabling stateless operations, horizontal scaling, and high resilience in 5G Core.
• Authentication & Security: Manage the AUSF (Authentication Server Function), ensuring secure 5G AKA procedures and device identity integrity.
• Signaling & Protocol Analysis: Provide L2/L3 support for signaling issues across Diameter (S6a, Cx, Sh) and HTTP/2 (Service-Based Architecture) interfaces.
• Change Implementation: Prepare and validate Methods of Procedure (MOPs) for configuration changes, software upgrades, and patch deployments in a production environment.
• Cloud-Native Operations: Manage and troubleshoot network functions deployed as CNFs (Containerized Network Functions) within Kubernetes environments.
• Performance Analysis: Monitor service/operational KPIs, generate performance reports, and proactively identify bottlenecks in the subscriber data path.
• Vendor & Stakeholder Collaboration: Work closely with partners and internal teams to resolve escalated incidents within agreed SLAs.

Required Expertise:

• Subscriber Data Expertise: Deep hands-on experience with HLR, HSS, UDM, UDR, and AUSF.
• Shared Data Layer (SDL): Expert understanding of stateless architecture and the separation of compute and storage using SDL patterns in 5G Core.
• 5G Core Knowledge: Strong understanding of 3GPP 5G Standalone (SA) architecture, specifically the Nudm, Nudr, Nausf, and Nnrf interfaces.
• Signaling Mastery: Expert in Diameter and HTTP/2/JSON/REST API signaling analysis.
• Troubleshooting: Ability to perform end-to-end trace analysis (Wireshark/Tshark) for call flows, authentication, and registration procedures.
• Cloud/Containerization: Working experience with Kubernetes, Docker, and OpenStack. Proficiency in monitoring pod health and resource utilization.
• Automation & Scripting: Experience in automating routine operational tasks using Python or Bash.
• Telecom Protocols: Solid understanding of 3GPP protocols including SS7, SIGTRAN, Diameter, LDAP, and SOAP.

Preferred Qualification

• Total Experience: 8 -15 years
• Good Knowledge of Telecom 4G/5G/LTE/VoLTE Networks and Call flows
• Preferred nodes are: CSD, DRA, DEA, NLS, SPS, PCRF, OCS, NCC, NPC, CBAM, Ground0, CGF, NWR, NatRef, NatLog, IOT-DC, IOT-CSG, IOT-SMP.
• Strong understanding of RTP, RTCP, H.248, SIP, Diameter, SS7, TCP/UDP, M3UA, SOAP, HTTP, HTTPS. LDAP, RTP other 3GPP Protocol.
• Good understanding of Linux environment.
• Experience of working on VNF/CNF technologies.
• Good understanding for Networking and cloud.
• Good communication skills.

RAKUTEN SHUGI PRINCIPLES:

Our worldwide practices describe specific behaviours that make Rakuten unique and united across the world. We expect Rakuten employees to model these 5 Shugi Principles of Success.

• Always improve, always advance. Only be satisfied with complete success - Kaizen.
• Be passionately professional. Take an uncompromising approach to your work and be determined to be the best.
• Hypothesize - Practice - Validate - Shikumika. Use the Rakuten Cycle to success in unknown territory.
• Maximize Customer Satisfaction. The greatest satisfaction for workers in a service industry is to see their customers smile.
• Speed!! Speed!! Speed!! Always be conscious of time. Take charge, set clear goals, and engage your team.