Quality-based synchronization methods of multimedia objects

Abstract

It is critical for applications to obtain enough quality of service (QoS) from multimedia objects. Not only states but also QoS of objects are changed by methods. The objects are manipulated by multiple transactions. Here, the objects are required to be consistent. We discuss new types of consistency of multimedia objects with respect to QoS. Since it takes a longer time to perform a method on multimedia objects, the throughput of the system is decreased if objects are exclusively locked in traditional concurrently control. We separate a concurrency control mechanism to two orthogonal ones, one for serializing transactions and the other for mutually exclusive access to objects. The timestamp ordering protocol is adopted for the former one and the locking protocol for the latter. © 2002 Elsevier Science Inc. All rights reserved.