This document provides an overview of SK Telecom's use of big data analytics and Spark. Some key points: - SKT collects around 250 TB of data per day which is stored and analyzed using a Hadoop cluster of over 1400 nodes. - Spark is used for both batch and real-time processing due to its performance benefits over other frameworks. Two main use cases are described: real-time network analytics and a network enterprise data warehouse (DW) built on Spark SQL. - The network DW consolidates data from over 130 legacy databases to enable thorough analysis of the entire network. Spark SQL, dynamic resource allocation in YARN, and integration with BI tools help meet requirements for timely processing and quick