X-Communicator: implementing an advanced adaptive SIP-based user agent for multimedia communication

Our paper describes a SIP and RTP based software component which is platform independent and is adaptable to various network infrastructures. The software component, named "X-Communicator" is capable of multimedia communications, including audio, video, text (instant messaging), secure file transfer and desktop streaming, with the last three features currently being implemented. The goal is to provide a complete remote-assistance solution and to make the system capable of adjusting to dynamic environment changes. X-Communicator features NAT handling capability and uses intelligent network detection components to identify network infrastructure. For multimedia RTP data stream transmission, it utilizes P2P streaming. The system uses SIP for transferring various control information and implements security. X-Communicator is very user-friendly and can interoperate with other SIP based standard user agents (soft or hard phones) and adjusts its communication capability accordingly. The paper proposes different possible network environments and the software\´s capability. X-Communicator is currently implemented as a functional prototype and is undergoing further development.