1. A method of synchronizing side information for use in interactive compression between a mobile communication device and a server, the method comprising: receiving information stored in a side information database of one of the mobile communication device or the server, the information including nodes which index, point to, or contain compression state information that provides parameters of previously completed compressions; identifying common nodes that are common to both the side information database of the one of the mobile communication device or the server and a side information database of the other of the mobile communication device or the server; and creating a common hierarchical node index, wherein the common hierarchical node index comprises the common nodes, and wherein the creating of the common hierarchical node index comprises updating an existing hierarchical node index stored at the mobile communication device or at the server by deleting nodes not identified as common nodes.