This document provides an overview of the Big Data CDR Analyzer project. The project aims to develop a system called Kanthaka that can analyze large volumes of Call Detail Records (CDR) to select eligible mobile users for promotional offers in real-time. Kanthaka will use Cassandra, a NoSQL database, and be able to process 30 million records per day with results within 30 seconds. The document compares technologies, describes the architecture, discusses risks and remedies, and lists deliverables including a research paper and final report.