When implementing multi-user cooperation systems in networked virtual environments, synchronizing local representations of shared virtual world has to be considered. It involves distributing and storing the data that represent users’ activity in the virtual world. In this paper we propose a concept of general variables, which formalizes the task of distributing, journaling and locking the data ...

Tremendous increase of Internet traffic demands high speed, large capacity IP switch routers. The introduction of multi-server switch architectures not only makes it possible to scale to larger switch capacities, but also imposes special requirements on scheduling algorithms running in the central scheduler. In this paper, we model the multi-server switch scheduling problem as a maximum biparti...

A fundamental privacy problem in the client-server setting is the retrieval of a record from a database maintained by a server so that the computationally bounded server remains oblivious to the index of the record retrieved while the overall communication between the two parties is smaller than the database size. This problem has been extensively studied and is known as computationally private...

In this paper, a multi-user multi-server queuing system is studied in which each user is constrained to get service from a subset of servers. In the studied system, rate allocation in the sense of max-min fairness results in multi-level fair rates. To achieve such fair rates, we propose CMFQ algorithm. In this algorithm users are chosen for service on a packet by packet basis. The priority of e...

In this paper, we investigate the response time of a multi-server processor sharing (PS) model. A multi-server PS model is a PS queue but the number of requests which can be processed simultaneously is limited by a threshold. An arriving request has to wait in the queue if the number of requests exceeds the threshold. Assuming Markovian arrival input of requests and general processing time dist...

This paper analyzes a discrete-time $Geo/Geo/c$ queueing system with multiple working vacations and reneging in which customers arrive according to a geometric process. As soon as the system gets empty, the servers go to a working vacations all together. The service times during regular busy period, working vacation period and vacation times are assumed to be geometrically distributed. Customer...