It is shown that, particularly for terrestrial cellular telephony, the interference-suppression feature of CDMA (code division multiple access) can result in a many-fold increase in capacity over analog and even over competing digital techniques. A single-cell system, such as a hubbed satellite network, is addressed, and the basic expression for capacity is developed. The corresponding expressions for a multiple-cell system are derived. and the distribution on the number of users supportable per cell is determined. It is concluded that properly augmented and power-controlled multiple-cell CDMA promises a quantum increase in current cellular capacity. >

On the capacity of a cellular CDMA system

Praise for the Third Edition: "This is one of the best books available. Its excellent organizational structure allows quick reference to specific models and its clear presentation . . . solidifies the understanding of the concepts being presented."IIE Transactions on Operations EngineeringThoroughly revised and expanded to reflect the latest developments in the field, Fundamentals of Queueing Theory, Fourth Edition continues to present the basic statistical principles that are necessary to analyze the probabilistic nature of queues. Rather than presenting a narrow focus on the subject, this update illustrates the wide-reaching, fundamental concepts in queueing theory and its applications to diverse areas such as computer science, engineering, business, and operations research.This update takes a numerical approach to understanding and making probable estimations relating to queues, with a comprehensive outline of simple and more advanced queueing models. Newly featured topics of the Fourth Edition include:Retrial queuesApproximations for queueing networksNumerical inversion of transformsDetermining the appropriate number of servers to balance quality and cost of serviceEach chapter provides a self-contained presentation of key concepts and formulae, allowing readers to work with each section independently, while a summary table at the end of the book outlines the types of queues that have been discussed and their results. In addition, two new appendices have been added, discussing transforms and generating functions as well as the fundamentals of differential and difference equations. New examples are now included along with problems that incorporate QtsPlus software, which is freely available via the book's related Web site.With its accessible style and wealth of real-world examples, Fundamentals of Queueing Theory, Fourth Edition is an ideal book for courses on queueing theory at the upper-undergraduate and graduate levels. It is also a valuable resource for researchers and practitioners who analyze congestion in the fields of telecommunications, transportation, aviation, and management science.

Fundamentals of Queueing Theory

Technical foundations introduction software reliability and system reliability the operational profile software reliability modelling survey model evaluation and recalibration techniques practices and experiences best current practice of SRE software reliability measurement experience measurement-based analysis of software reliability software fault and failure classification techniques trend analysis in validation and maintenance software reliability and field data analysis software reliability process assessment emerging techniques software reliability prediction metrics software reliability and testing fault-tolerant SRE software reliability using fault trees software reliability process simulation neural networks and software reliability. Appendices: software reliability tools software failure data set repository.

/pdf/handbook-of-software-reliability-engineering-32dwvaljmm.pdf

Handbook of software reliability engineering

To support bursty traffic on the Internet (and especially WWW) efficiently, optical burst switching (OBS) is proposed as a way to streamline both protocols and hardware in building the future gener...

Optical burst switching (OBS) - a new paradigm for an optical Internet

The emerging software defined networking (SDN) paradigm separates the data plane from the control plane and centralizes network control in an SDN controller. Applications interact with controllers to implement network services, such as network transport with quality of service. SDN facilitates the virtualization of network functions so that multiple virtual networks can operate over a given installed physical network infrastructure. Due to the specific characteristics of optical (photonic) communication components and the high optical transmission capacities, SDN-based optical networking poses particular challenges, but holds also great potential. In this article, we comprehensively survey studies that examine the SDN paradigm in optical networks; in brief, we survey the area of software defined optical networks (SDONs). We mainly organize the SDON studies into studies focused on the infrastructure layer, the control layer, and the application layer. Moreover, we cover SDON studies focused on network virtualization, as well as SDON studies focused on the orchestration of multilayer and multidomain networking. Based on the survey, we identify open challenges for SDONs and outline future directions.

Software Defined Optical Networks (SDONs): A Comprehensive Survey

This paper presents a closed form expression and a Markov model estimating packet loss in a bufferless hybrid circuit and packet switched OpMiGua node. Prior traffic analysis of hybrid network nodes are based on preemptive and queue-based priority mechanisms, however, in this article we focus on the time-window approach with its associated reservation induced blocking (RIB). A closed form expression for packet loss is found by minimizing the RIB and is proved to be asymptotically exact for increasing length of circuit packets. A Markov model accounting for the effect of RIB is proposed and simulation is used to determine its accuracy. For lower than 85% share of circuit switched traffic, the respective median and 95- percentile for the relative error equals 10% and 25%. Finally, when circuit packets are aggregated into bursts the total packet loss is reduced for sufficiently high share of circuit traffic. The mechanisms behind this performance gain are identified and methods to maximise its effect are proposed.

Analysis of a Bufferless OpMiGua Node

In this paper we propose a novel Markov model to evaluate the performance of an asynchronous optical packet switch (OPS) equipped with limited range wavelength converters (LRWCs). The model is used for calculating the packet loss ratio (PLR) as a function of the normalized system load and the conversion range of the LRWC, when a circular wavelength conversion policy is adopted. The closed form expression of the PLR is given. We also build a discrete event simulator to evaluate the present model. Results show that the proposed approximate model gives upper bounds for the PLR and is satisfactory under different network scenarios.

Performance modeling of asynchronous bufferless optical packet switches with limited range wavelength converters

This paper investigates packet loss in multi-service Optical Packet Switched (OPS) networks, in which the Preemptive Drop Policy (PDP) is adopted to implement QoS differentiation. A novel approximation model is proposed. In contrast with existing multi-dimensional Markov model, which focuses on analyzing the small system with only two service classes and results in non-closed form expressions of the packet loss ratios (PLRs), our model has four major advantages: 1) it is applicable to analyzing a general multi-service scenario, independent of the number of service classes and wavelengths; 2) the closed form expressions of the PLRs can be derived directly; 3) the computational complexity is reduced dramatically; 4) this model shows excellent extensibility for analyzing larger system which supports more service classes or wavelength channels per fiber. The analytical values are compared with simulation results for a three-service OPS network. Results show that the proposed model provides a high degree of accuracy in the PLRs under different network scenarios.

A novel approach in modeling multi-service Optical Packet Switched networks with the Preemptive Drop Policy

The research agenda in optical burst switching in e-Photon/ONe (Tutorial)

Integrated hybrid optical networks (IHON) add statistically multiplexed (SM) packet traffic to increase the utilization of the wavelength channels dedicated to optical circuit switched traffic. SM packets are inserted in the variable sized free gaps in-between circuit switched packets. Some packets are too large for fitting in a specific gap, hence the utilization of the gaps decides the achievable throughput efficiency of the network. Segmenting SM packets, allowing also small gaps to be exploited, comes with the cost of adding extra processing and segmentation overhead. Hence, the number of segmented packets should therefore be minimized. In this paper we propose a novel rate-adaptive segmentation scheme (RAS), increasing the gap utilization while minimizing the number of segmented packets. The algorithm dynamically adapts the SM packet length pattern to fill the fragmented bandwidth and increase the throughput. Simulation results show that the scheme heightens the utilization from 73% to 89%. Furthermore, we propose a bounded delay scheme that minimizes the delay and bounds the jitter by droppings old head-of-line packets reducing packet loss ratio by 3%.

Norvald Stol

Papers

Analysis of a Bufferless OpMiGua Node

Performance modeling of asynchronous bufferless optical packet switches with limited range wavelength converters

A novel approach in modeling multi-service Optical Packet Switched networks with the Preemptive Drop Policy

The research agenda in optical burst switching in e-Photon/ONe (Tutorial)

A rate-adaptive segmentation algorithm for integrated hybrid optical networks