The design and development process of complex systems require an adequate methodology and efficient instrumental support in order to early detect and correct anomalies in the functional and non-functional properties of the solution. In this article, an unified experimentation framework (UEF) providing experimentation facilities at both design and development stages is introduced. This UEF provides a mean to achieve experiment in both simulation mode with UML2 models of the designed protocol and emulation mode using real protocol implementation. A practical use case of the experimentation framework is illustrated in the context of satellite environment.

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The design and development process of communication protocols and real-time systems and particularly transport protocol mechanisms requires adequate methodology and efficient instrumental support. In this paper, an extensible and QoS-oriented development framework integrating design and simulation with UML (Unified Modeling Language), and implementation and evaluation with emulation is introduced. An early use of the proposed framework is illustrated with the design and development of simple transport mechanism.

MITv is a proposition for interactive television to be deployed using an association of current distribution television systems (e.g., satellite DVB-S, cable DVB-T, TV over xDSL, etc.) and classical Internet infrastructure. MITv makes use of the natural association between broadcasted TV programs and associated interactive contents to manage replication of those contents over an ad-hoc infrastructure. The replication phase can be based on IP multicast over satellite service, providing a high performance and realistic way to convey the interactive content over the geographically distributed replication units. The proximity between replication units and end-users then allow a very high quality for interactive media presentation by way of an access network such as xDSL. The MITv system was entirely developed and tested in real conditions through a satellite/xDSL network emulator.

The paper assesses the potential of Java for developing both portable and efficient communication software. Specifically, this paper presents and compares implementation of a multimedia transport protocol, POC, using the Java and C languages. Performances measurement are applied to the transport of MPEG streams.

A partial order and partial reliable connection (POC) is an end-to-end transport connection authorized to deliver objects in an order that can differ from the transmitted one. The service that this connection provides is also authorized to lose a number of objects. The POC approach establishes a conceptual link between both connectionless best-effort (CL) and connection oriented (OC) protocols. This approach is motivated by the fact that heterogeneous CL networks such as the Internet are plagued by unordered delivery of packets and losses, which tar the performances of current protocols. Moreover, it has been showed, in several research works, that out of order delivery is able to alleviate the use of network resources such as memory and bandwidth, and reduces end-re-end transit delay. But, in order to take advantage of these benefits, applications must be able to relax some transport constraints. A temporal extension of POC, called TPOC (for Temporal POC), is introduced. TPOC offer a conceptual framework, which allow the QoS of distributed multimedia applications to be fully taken into account. The architecture for offering a TPOC transport service is introduced and evaluated for the transport of MPEG video streams. The authors demonstrate that POC connections fill not only the conceptual gap between CL protocols (such as UDP) and OC protocols (such as TCP) but also provides real performances improvements for the transport of multimedia streams such as MPEG video.