The Internet multimedia streaming increased proportional to the number of streaming users and from 2005 peer-to-peer media streaming received a substantial amount of research attention and was applied for both live and on-demand video streaming. This technique succeeded to provide a large number of multimedia streams while consuming less bandwidth than in the case of a client-server architecture. Multimedia streaming is a complex subject, it widens over various computer science fields as the networking area, multimedia compression area and the security area. Due to the increasing need of multimedia streaming applications and the need for continuous communication with harsh constraints such as real-time communication, low bandwidth and content security, the need for a flexible and extensible tool is justified, and the main purpose of such a tool is to facilitate the development of applications such as Goober (9), IConf (10), Ekiga (11) or Skype (12). The responsibilities of such SDK are to capture efficiently multimedia information from a web camera and/or a microphone and send them to its peer. The proposed SDK was built on the .NET Framework 4.5 based on a hybrid peer-to-peer architecture. The SDK can be integrated on multiple .NET platforms such .NET Framework 4.5, Silverlight, and Windows Phone 8, and due to its flexibility it can be used by desktop clients, web clients and mobile clients. From a communication perspective, the SDK starts several independent services which capture incoming data, and uses dynamic proxy objects to send data to its peers, services which assure the necessary degree of parallelism needed to have a responsive application with real-time communication.