In this paper, we survey techniques for routing and performance analysis of Low Earth Orbit (LEO) systems. We first review the basic structure of LEO satellite communications and present the main characteristics of LEO systems. The dynamic characteristics of LEO systems make the performance analysis and routing problem quite complicated. In this study, we review some of the proposed solutions t...

In this paper, we propose a distributed contention resolution scheme to reduce blocking probability in optical burst-switching networks. The scheme takes priority, propagation delay from the ingress router, and the burst-size into account to resolve contention, and guarantees that at least one of the bursts succeeds when contention occurs. We use a control packet to delay transmission of the co...

only wavelength translation is higher than that when TSI is introduced, either alone or in addition to the wavelength translation. However, for one-and two-hop paths, the observed blocking probability with wavelength translation alone is below that obtained with TSI, and above the blocking probability for the corresponding paths in networks without either wavelength translation or TSI. Similarl...

In this paper we give insight into the performance of Dynamic Spectrum Access Networks (DSAN), analyzing Quality of Detection of Primary User (PU) and DSAN blocking probability, when the channel is under the effect of log-normal shadowing. Specifically we propose a distributed power conserving PU detection architecture and investigate the impact of PU detection accuracy on DSAN performance. We ...

We propose and analyze layered switch architectures that possess high design flexibility, greatly reduced switch size, and high expandability. The improvement in loss and crosstalk due to the reduced switch size is also discussed. Theoretical models have been developed to compute the network blocking probability using these architectures. Low blocking probability and high network utilization ar...

Stochastic processes have been widely employed in order to assess the network layer performance of Optical Packet Switched (OPS) networks. In this paper we consider how the Engset traffic model may be applied to evaluate the blocking probability in asynchronous bufferless OPS networks. We present two types of the Engset traffic model, i.e. the Engset lost calls cleared traffic model and the Eng...

In cellular communication systems, channel assignment schemes are very important to improve teletraf®c performance characteristics. Because of the overlapping design of the cells in cellular communication systems, a mobile user is capable of communicating with two different bases. In this paper, a new channel assignment scheme is proposed to improve the blocking probability of a cellular commun...

Vertical handover is essential to ensure service continuity in a heterogeneous network. Multi-criteria decision is proposed to reduce handover rate and optimizing usage of network resource compared to the conventional handover decision, which used single criteria. The algorithm is evaluated by assessing the performance in terms of number of handoff, load balance index, and network blocking prob...

Supporting multiple priority calls, we propose the queueing strategies which efficiently manage the queue to reduce the blocking probability with multiclass calls in multiservice personal communications services (MPCS). The two queueing schemes are proposed and are shown the analytic model with …n 1 1† class calls. Numerical results demonstrate that the two proposed schemes show the improved pe...

In this paper, we propose an Adaptive Hybrid Transmission schemes for free space optical communication. Proposed algorithm utilizes hybrid mechanism which combines Multi-channel multicasting and unicast scheme to enhance not only service over service blocking probability but also reduce overall bandwidth consumption of the free space optical communication system which has very limited resources...