THE USAGE OF ADVANCE RESERVATION MECHANISMS IN DISTRIBUTED MULTIMEDIAAPPLICATIONS

Distributed multimedia applications impose specific requirements conce rning quality-of-service. To satisfy these requirements, the reservati on of network and end system resources is necessary. Particularly for applications with relatively long duration and significant importance from a business point of view, it is desirable to do such reservations well in advance of the actual run-time. This way, the probability of resource availability can be increased, and network utilisation can be improved. Based on our design and implementation of a mechanism fbr r esource reservation in advance (ReRA), this paper describes the use of this approach within dedicated application scenarios. In particular, we both address videoconferencing based on the MBone tools and video-o n-demand services based on extended client/server protocols. For these scenarios, reservation requirements are derived and typical design tr ade-offs concerning advance reservation mechanisms are discussed. From a practical point of view, the mapping of advance reservations onto e ither RSVP or onto direct ATM connections is outlined. (C) 1998 Elsevi er Science B.V. All rights reserved.