EarthLink SIPshare is a simple, SIP-based proof-of-concept content sharing application, demonstrates the viability of SIP as a protocol over which peer-to-peer (P2P) applications other than the well-known voice and video cases may be implemented. As a proof-of-concept application, share documents, photos, and other files with peers on the network via standard SIP messaging, and completed using a simple UDP-based file transfer protocol. SIPshare is a Java application.