Home Subscriber Server – Korea Telecom

Altibase enables Korea Telecom to cope with problems with user authentication and authorization that undermine its IP multimedia subsystem. Altibase was chosen over Oracle TimesTen.

Use Case: Home Subscriber Server (HSS)

Current Customers: Korea Telecome (KT)

Industry: Telecommunications


KT is South Korea’s largest telecommunications service provider with over 40 million subscribers. With deep wired and wireless expertise, KT has tremendous strengths in fiber optics, digital multimedia services and both wired and wireless broadband services.


KT sought reliable, real time database solutions for its core HSS. HSS uses a database that manages such subscriber-related information in LTE and IP multimedia subsystem network as mobile management, user authentication, security and service processes.

However, the growing demand from its 40 million customers utilizing the company’s IP multimedia core network subsystem rendered KT’s legacy database obsolete. Other problems related to its legacy database systems included:

  • HSS is a service that requires extremely high throughput and low latency as well as stability and high availability. The existing databases failed to meet those requirements.

  • KT needed a comprehensive solution that could easily handle over 1 million subscribers per second for numerous concurrent authentication and authorization attempts.
  • KT also required a future-proof database solution for its ever increasing demand from user growth and for multimedia services.


After a series of benchmark tests, Altibase was chosen over Oracle TimesTen. Altibase’s in-memory features have helped KT with seamless management of all HSS-related requirements while creating a robust foundation for KT’s future growth.

  • KT can store and process subscriber location information in real time.
  • KT has been enabled to manage authentication information without risking to lose any of it via Altibase’s unique replication functions.


Altibase arms KT with the ability to authenticate up to 100 million times per day, future-proofing the company’s ability to handle future growth.

  • Altibase allows for performance enhancement by multiples vis-a-vie its legacy systems.
  • With the adoption of Altiabse, KT has been able to operate HSS more reliably without data losses and processing delays.
  • Altibase has proved to excel Oracle TimesTen in overall performance as well as in complex queries.
  • In addition, Altibase performs more stable than Oracle TimesTen in terms of data durability in case of system failures.
  • Altibase is now used as the core database for many of KT’s other mission critical systems.