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This paper describes some experience we have done in the development of multimedia application inside a distributed architecture. The requirements of such environment are the following: (1) to support high quality multimedia data; (2) to be independent from the hardware platform and from the transport protocol; (3) to be cheap form the client side. The goals to reach were twofold: to develop a client/server system for the management and transmission of MPEG bitstreams, and to optimize the transmission of MPEG over ATM networks. The first goal was reached using standardized technologies in the implementation of the system components: a DSM-CC server has been realized based on CORBA Services, which is able to manage MPEG streams as specified in the ISO DSM-CC document. The client module has been realized using Java. The system, originally written for Sun Solaris has been successfully tested on different Unix and NT platform. The evaluation of quality and performance of the transmission of MPEG over ATM was made using three types of signaling: classical IP over ATM,, LAN emulation and the ATM Native algorithm implemented over FORE API. Both classical IP over ATM and LAN Emulation allows the transparent use of ATM for application written using the widespread TCP/IP family of protocols, but they introduce an overload of data which could not be suitable for real-time transmission. Of course, native ATM gets better performance than Classical IP over ATM and LAN Emulation but binds the application to run only on ATM networks, and at the moment it is hardware dependent.
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