We consider the transmission of variable bit rate (VBR) video over a network offering a guaranteed service such as ATM VBR or the guaranteed service of the IETF. The guaranteed service requires that the flow accepted by the network has to be conforming with a traffic envelope . In this context, the output of the video encoder is constrained by the traffic envelope defined at the network entry p...

Consider a queueing system in which K sources each generate 1=M units of work once every time unit. The phases of the sources are mutually independent, and each phase is uniformly distributed over the unit interval. The queue is served at unit rate. The distribution of the typical work and the maximum work are studied both for nite K and M and in the limit of large K and M. The limiting maximum...

Denial Of service (DoS) attacks has become a major problem to intranet and Internet services. DoS attacks can be detected and eliminated using existing efficient Active Queue Management (AQM) schemes like RED. A new kind of DoS attacks have become more common in today’s Transmission control protocol (TCP) services, i.e., Low Rate Denial of Service (LDoS) attacks. LDoS attacks will degrade the p...

tourism, combined with the phrase medical, seems to be a new form of tourism which has gained huge popularity in recent decades. though, a number of literatures available with regard to the tourism industry and the competitiveness of the destination, however, the major aspects which determine the satisfaction of medical tourists are hardly focused specifically on malaysia. there is a lack of em...

in this paper the design and implementation of fault tolerable architecture for scientific workflow engines is presented. the engines are assumed to be implemented as composite web services. current architectures for workflow engines do not make any considerations for substituting faulty web services with correct ones at run time. the difficulty is to rollback the execution state of the workflo...

Most of today’s organizations are still far from profiting from the full potential of web service technology. Organizations invoke each other’s web services, but do hardly synchronize the life cycles of individual web services with each other. When realizing an integrated service this might cause failures and requires a governance method for synchronizing the life cycles among organizations. In...

The asymptotic decay rate of the sojourn time of a customer in the stationary M/G/1 queue under the Foreground Background (FB) service discipline is studied. The FB discipline gives service to those customers that have received the least service so far. We prove that for light-tailed service times the decay rate of the sojourn time is equal to the decay rate of the busy period. It is shown that...