XCAP Authentication Server

The Challenge

Telecommunications providers require robust authentication infrastructure to securely handle SIM-based authentication requests for mobile services. The system needed to:

• Process high volumes of authentication requests with minimal latency
• Maintain secure connections with external gateway systems and resource servers
• Provide real-time monitoring and alerting for operational teams
• Generate comprehensive reports for transaction analysis and business intelligence
• Support both HTTP and HTTPS protocols for backward compatibility
• Handle database scalability challenges with growing transaction volumes
• Ensure high availability and fault tolerance

The existing system faced challenges with performance bottlenecks, limited observability, manual reporting processes, and security concerns with unencrypted communications. There was also a need to modernize the technology stack to leverage newer Java features and Spring Boot capabilities.

The Solution

Architecture Design

Architectural Decisions

1. Microservices Architecture: Separated authentication server, data loader, and report viewer into independent modules for better scalability and maintainability

2. Connection Pooling: Implemented C3P0 connection pooling for database connections and custom HTTP client pooling for external service communication to handle high concurrent requests

3. Dual Database Strategy: Separated authentication cache database from reporting database to optimize performance and allow independent scaling

4. Asynchronous Processing: Implemented async data loading and report generation to prevent blocking the main authentication flow

5. Health Monitoring: Integrated SNMP-based monitoring for database connectivity, external service health, and TPS threshold alerts

6. SSL/TLS Support: Added configurable HTTPS support for secure communication with resource servers while maintaining HTTP backward compatibility

Key Contributions & Problem Solutions

Tech Stack

Impact & Results

Business Impact

• Service Capability: Enabled handling of high-volume SIM authentication requests with enterprise-grade reliability (99.9% uptime).
• Operational Savings: Automated reporting and self-service dashboards slashed manual operational effort by 90% and support tickets by 70%.
• Compliance & Risk: Secured external communications via HTTPS/TLS, meeting strict industry security standards and protecting user data.

Technical Efficiency

• Modernization: Successful migration to JDK 21 and Spring Boot 3 unlocked virtual threads and performance gains, future-proofing the stack.
• Optimized Throughput: Database partitioning and connection pool tuning increased concurrent request handling capacity by 40%.
• Resilience: Automated data recovery mechanisms achieved a 100% success rate in restoring data after system interruptions.

Operational Excellence

• Proactive Monitoring: SNMP integration and real-time TPS alerting shifted operations from reactive troubleshooting to proactive capacity management.
• Rapid Troubleshooting: Enhanced logging and standardized error codes reduced Mean Time To Resolution (MTTR) by 60%.

Key Learnings

1. Incremental Migration Strategy: The gradual migration from HTTP to HTTPS and JDK 8 to JDK 21 taught the importance of maintaining backward compatibility during major upgrades, enabling zero-downtime deployments.

2. Database Architecture: Separating authentication and reporting databases demonstrated the value of optimizing data storage strategies based on access patterns and performance requirements.

3. Observability First: Implementing comprehensive monitoring and logging from the beginning significantly improved troubleshooting capabilities and enabled proactive issue resolution.

4. Performance Optimization: Database partitioning, connection pooling, and bulk loading optimizations showed that infrastructure-level improvements often provide the most significant performance gains.

5. Recovery Mechanisms: Building automated recovery systems proved critical for maintaining data integrity and reducing manual intervention during failures.