This paper presents a two-phase handoff management scheme for synchronization algorithms of wireless multimedia systems. This scheme allows mobile hosts to receive multimedia units without delivery interruption while they are moving from one cell to another cell. The messages passing among mobile hosts, base station and servers include a time stamp to compute delay time for each multimedia unit for each server. The scheme always search for a Quasi-receiver among base stations with which mobile hosts are communicating to synchronize multimedia units. We discuss the algorithms and also present a set of simulation experiments to evaluate the performance of our scheme using message complexity and buffer usage at each frame arrival time. Our results indicate that our scheme exhibits no underflow within the bounded delivery time.

Recent advances in mobile computing and distributed multimedia systems allow mobile hosts (clients) to access wireless multimedia systems anywhere and at anytime, but not without creating a new set of issues and trade-offs. To the best of our knowledge, there has been very little research in dealing with the synchronization problem in wireless and mobile multimedia systems. In this paper, we propose an efficient distributed synchronization algorithm using quasi-sink for wireless and mobile multimedia systems to ensure and facilitate mobile client access to multimedia objects. We discuss the algorithm and provide its proof of correctness. We also present a set of simulation experiments to evaluate the performance of our scheme using message complexity and buffer usage at each frame arrival time. Our results indicate that our scheme exhibits a significant low message complexity and no underflow and overflow within the bounded delivery time.

The recent advances in mobile computing and distributed multimedia systems allow mobile hosts (clients) to access wireless multimedia systems anywhere and at anytime, but not without creating a new set of issues and trade-offs. To the best of our knowledge, there are very little research done that deal with the synchronization problem in wireless and mobile multimedia systems. In this paper, we propose an efficient distributed synchronization algorithm for wireless and mobile multimedia systems to ensure and facilitate mobile clients accessing multimedia objects. We discuss the algorithm and provide its proof of correctness in a wireless environment.

The rapid development in portable computing platforms, distributed multimedia systems and wireless communication technologies has led to a significant interest in mobile multimedia and wireless networking. Video entertainment and multimedia Internet access over wireless networks are examples of future wireless personal communication systems. These, however, incur challenging technological issues. The synchronization of the multimedia objects among mobile clients is one of the most important of these issues. The task of synchronization in wireless multimedia systems is to eliminate variations and delays incurred during the transmission of multiple-media streams and to maintain the temporal order among the various media streams. We propose an efficient distributed multimedia synchronization algorithm for wireless and mobile multimedia systems to ensure and facilitate mobile clients' access to multimedia objects. We discuss the algorithm and provide its formal proof and correctness.

We present an efficient distributed dynamic channel allocation algorithm for mobile communications systems. The algorithm is based upon the mutual exclusion model, where the channels are grouped by the number of cells in a cluster and each group of channels cannot be shared concurrently within the cluster. We discuss the algorithm and prove its correctness. We also show that the algorithm requires at most (worst case) O(N/sub g/*N/sub n/logN/sub n/) messages, where N/sub g/ is the number of groups and N/sub n/ is the number of neighbors. This is compared to Choy's (1995) algorithm which requires O(N/sub g//sup 2/*N/sub n/), where N/sub g/ is the number of groups. Our simulation experiments indicate that the DDRA algorithm outperforms previous schemes. A 5% reduction in the denial rate, and a 10-30% reduction in the acquisition time channel were obtained using our algorithm when compared to the previous algorithm.

Recent demand for mobile telephone service have been growing rapidly while the electro-magnetic spectrum of frequencies allocated for this purpose remain limited. Any solution to the channel assignment problem is subject to this limitation, as well as the interference constraints between adjacent channels in the spectrum. Channel allocation schemes provide a flexible and efficient access to bandwith in wireless and mobile communication systems.

Two new algorithms for the distributed static resource allocation problem are presented. The first algorithm, which shows excellent average case behavior in simulation requires the maintenance of a global queue. The second, which needs only local communication, has polynomial waiting time and exhibits better average case behavior than the only other known polynomial time algorithm. Both algorithms have polynomial message complexity.>