Real Time Rating System – SK Telecom

Altibase enables SK Telecom to bill per-second, per-individual in real time, eliminating collection problems and reducing customer discontent. Altibase is deployed to host recent data as a front end to Oracle which is used as the repository for hosting historical data.

Use Case: Billing, Call Detail Record (CDR) processing

Current Customers: China Telecom, China Unicom, China Mobile, KT, SK Telecom and LG Uplus

Industry: Telecommunications


SK Telecom is the largest mobile service provider in South Korea with over 26 million subscribers. SK Telecom introduced the world’s first CDMA technology and was awarded for its leadership in LTE. Currently, SK Telecom is paving the way for LTE-advanced and 5G capabilities.[1]


Before SK Telecom deployed Altibase, it had been adopting Oracle on a legacy mainframe-based IT infrastructure for its Real Time Rating System (RTRS). However, SK Telecom identified the following limitations of its legacy DBMS.

  • SK Telecom’s billing service suffered from major delays as the number of subscribers grew substantially.
  • With growing demands on the legacy system, database-related TCO became progressively onerous.
  • The company was unable to detect and shut off service when prepaid balances were depleted.
  • The inability to accurately detect customer balances resulted in negative balances and uncollected funds.


SK Telecom adopted Altibase in 2002 for its RTRS for the first time. Since then, Altibase has been deployed for its in-memory portion as a front end to Oracle which is used to host historical data in order to enhance the performance and achieve cost savings for SK Telecom’s DB need. The net result has been higher performance with lower TCO.


  • SK Telecom is now able to precisely check and act on customer balances.[2]
  • It also has the capacity to process customer usage on a per-second basis. This dramatic shift provides substantial savings to customers.[3] When this feature was first introduced, SK Telecom was able to capitalize on this newly added billing prowess to spearhead a significant marketing campaign. Other telecommunications companies followed suit.
  • Revenue losses resulting from undetectable free usage and uncollected negative balances have been eliminated.
  • Customers have access to their balances in real time and without error.
  • Customer satisfaction, loyalty, retention and acquisition are enhanced.
  • The company replaced its aging and expensive mainframe-based legacy system with an open UNIX platform, which resulted in lower TCO.
  • The company has the ability to efficiently integrate billing services for subscribers using multiple services.

Technical Details – Real Time Rating System

SK Telecom has achieved outstanding results with its RTRS by leveraging the key features of Altibase, specifically in the areas of high performance, open platforms and HA.

High Performance

Before the new RTRS powered by Altibase’s in-memory database performance was utilized, SK Telecom’s old billing and rating system was built and operated on a legacy IBM mainframe with an IBM DB2 DBMS in the back-end. The legacy system only allowed billing and rating processes to execute in batch/day processing windows.

An increasing number of subscribers and the introduction of new services resulted in an unmanageable number of database transactions, making batch-mode operation impossible. Furthermore, new services (i.e. prepaid plan) came with additional requirements demanding SK Telecom to detect and manage usage balances in real time, which was impossible with the legacy system. SK Telecom could only achieve a throughput of 150 million calls a day while system resource utilization was maxed out.

SK Telecom designed its new RTRS using a combination of Altibase in-memory database and Oracle’s on-disk DBMS. Altibase was deployed in its in-memory database mode to host recent data (up to 3-month old) as a front-end to an on-disk Oracle database which was used as the repository for hosting historical data.

Data integration between Altibase and Oracle was achieved by using Altibase’s OraAdapter tool. The new system allowed billing and rating processes to execute in real time. This real time process was critical for prepaid services since SK Telecom had to accurately detect negative customer balances. In addition, the new system achieved a throughput of 450 million calls a day while reducing system resource utilization to 50%.

Open Platform

With a mission critical system built on a legacy mainframe platform, SK Telecom faced difficulties in several areas. Due to high system procurement, upgrade and maintenance costs, TCO was growing at an unsustainable pace. The legacy system also did not offer flexibility for new application development. The limited number of application developers and administrators trained on legacy mainframe systems in the market exacerbated the problem further.

Altibase was the textbook solution. As an open system, it allowed SK Telecom to move to a UNIX based platform. As a standards-compliant DBMS, it has enabled SK Telecom to take advantage of a readily available pool of application developers and administrators at low cost.


Using the built-in replication feature, SK Telecom implemented Altibase based on active-active HA architecture. In this architecture, there were two instances of Altibase configured to simultaneously service different rating servers with improved reliability and fault-tolerance.


[1] SK Telecom now has 53% of market share representing over 27 million subscribers.
[2] The new system is 5.3 times faster than the legacy system with the added benefits of HA and replication.
[3] Per-second charging scheme saves SK Telecom’s customers an average of $14.5 million per annum.

Altibase – Downloading is Believing.