SMS Spam Blocking System – Korea Telecom

Korea Telecom replaced Oracle with Altibase for its SMS spam blocking system so that it could detect and block spam in real time.

Use Case: Spam Filtering System

Current Customers: KT and LG Uplus

Industry: Telecommunications


Korea Telecom (KT) is South Korea’s largest telecommunication service provider with over 40 million users. With deep wired and wireless expertise, KT has tremendous strength in fiber optics, digital multimedia services and both wired and wireless broadband services.


Spam text messages are a serious problem everywhere, and South Korea is no exception. KT’s Oracle-based legacy system could not accurately block messages because of its limited capabilities. The system filtered spam through a predefined set of keywords and phone numbers. As spam senders were getting smarter every day, the system was of no use.

  • To make matters worse, the system from time to time blocked legitimate messages.
  • KT needed solutions capable of determining whether a message was spam or legitimate instantly inside of one second. This function requires high performance with low latency on complex spam filtering tasks that Oracle databases could not timely handle.
  • KT needed databases that could help its system do the job.


KT has deployed Altibase since 2009 for real time spam detection.


  • With Altibase‘s in-memory feature, the system takes only 0.2 seconds to execute detection whereas it used to take 3 seconds with Oracle’s databases.
  •  With Altibase, KT could proactively protect its clients against ever-evolving spam techniques. For example, KT now can detect smishing (SMS phishing) attacks so that personal information would not be divulged inadvertently.

Altibase – Downloading is Believing.