Date Added: Nov 2010
The problem of Index Coding with Side Information (ICSI) was introduced by Birk and Kol,. It was motivated by applications such as audio and video-on-demand, and daily newspaper delivery. In these applications a server (sender) has to deliver some sets of data, audio or video files to the set of clients (receivers), different sets are requested by different receivers. Assume that before the transmission starts, the receivers have already (from previous transmissions) some files or movies in their possession. Via a slow backward channel, the receivers can let the sender know which messages they already have in their possession, and which messages they request. By exploiting this information, the amount of the overall transmissions can be reduced.