This work reports the results of some testing activities on the efficiency of MPEG video documents transmission in the framework of distributed multimedia databases and in presence of possible real time playout requirements. Tests have been carried out by means of a prototype of a distributed multimedia DBMS, both on local and wide area network (Internet) and with respect to different network loads. Such a prototype runs on top of a distributed environment and is based on a client-server architecture.
Our main goal is evaluating the applicability of TCP, UDP and RTP  in order to satisfy real time playout requirements with respect to the transmission of MPEG compressed video streams. In addition, the achievable performances are compared with those guaranteed by some widely used videoconferencing tools .
As it may be expected, we did not detect any kind of problem during the tests conducted on local area networks with respect to TCP: no substantial delivery delay has been detected and the network bandwidth resulted widely sufficient. Poor frame rates have been revealed only with respect to low computing power or displaying wide image sizes.
Author:- Lancia, Maurizio ( firstname.lastname@example.org)
Gaibisso, Carlo ( email@example.com)
Biondi, Vincenzo ( firstname.lastname@example.org)
Gambosi, Giorgio ( email@example.com)
Vitale, Maurizio ( firstname.lastname@example.org)