From QoS models and specifications to QoS mechanisms and implementations-do users care about network QoS?

Summary form only given, as follows. Distributed multimedia applications need QoS support from the network in order to be acceptable to the user. For several years, QoS models and specifications have been developed in research. Now, we have been moving to implementations and it can be expected that such mechanisms, e.g., offered by ATM, find large-spread use. This depends, however, on several factors such as suitability of mechanisms, end-to-end provisioning and costs. The focus of such work has been on network and partially on server techniques taking a "system point of view". Yet, users care only about the QoS at the user interface. While this has been the original driving force of the development of the above mentioned mechanisms, it remains to be reviewed if we have been able to meet this issue. An overview of QoS, its importance, its development, and the state of the art is presented. Following this, the suitability of the available mechanisms with respect to user and application requirements are discussed.