This paper discusses the principles of bus systems simulation for real-time applications. It uses a typical queuing model of a single bus with multiple processors, memories and I/O devices. The major criterion used in evaluation of real-time response is the bus access latency. An illustrative example of a VMEbus system with two arbitration protocols, round-robin and priority-based, for typical ...

The European Regulator Group (ERG) defines Bitstream Access Service as a wholesale service offered by a broadband network operator with significant market power to an Internet Service Provider, and identifies it as a market subject to regulation. This paper develops a cost model for the Bitstream Access Service under xDSL technology, following the recommendations of the ERG, considering differe...

Recently, there has been a rapid growing interest in new applications requiring quality of service (QoS) guarantees through wireless local area networks (WLAN). These demands have led to the introduction of new 802.11 standard series to enhance access medium supporting QoS for multimedia applications. However, some applications such as variable bit rate (VBR) traffic address some challenges in ...

Cognitive radio (CR) can significantly improve spectrum efficiency by allowing the secondary users to temporarily access the primary user’s under-utilized licensed spectrum. Spectrum mobility issues arise when the primary user appears at the channels being occupied by the secondary users. The secondary users return to the occupied channel because the primary users have the preemptive priority t...

In this paper a single server preemptive priority queuing system consisting of two types of customer units with Poisson arrival, exponential service time distribution and exponential vacation is analyzed. Two type of customer units of which higher priority units of unlimited Poisson input are served by bulk service rule and limited Poisson input of low priority units served singly. The bulk ser...