An open peer-to-peer based platform for scalable multimedia communication

摘要

This article describes an open platform for multimedia applications on a peer-to-peer network. A Voice-over-IP application was developed on it as proof-of-concept. The application allows users to call each other, to publish and query presence information, and to specify whether to allow or deny communication with other users at any given time. For session setup and management the Session Initiation Protocol is used, while audio communication is handled by the Real-Time Transport Protocol. User data is persistently stored on a peer-to-peer network using a distributed hashtable. A software architecture is presented to implement these requirements by means of two highlevel components: the Node, handling all client-side aspects of the system such as calling other users, querying presence and setting preferences, and the SuperNode, handling all server-side aspects such as storage and management of persistent user data, user location, call routing, presence management and monitoring of the underlying peer-to-peer network.