In this book, we focus on the design of efficient optical switch architectures with reduced complexity to resolve packet contention in asynchronous OPS networks. In particular, the main contributions of this book can be summarized as follows: (1) propose a new FDL-based switch architecture that achieves the same performance as that of best known architectures but with a reduced hardware complexity, (2) conduct a detailed study of the impact and complexity of using WCs in the design of optical switch architectures, and (3) develop and analyze a new hybrid OPS switch architecture that has a smaller packet loss, average switching delay, and hardware complexity compared to exiting optical switch architectures.
This book is aimed at understanding the concepts and methodologies involved in the recent Passive Optical Networks (PONs) which have evolved to provide much higher bandwidth at the lowest cost in the access networks. The WDM optical systems have totally revolutionized the telecommunication sector by opening up a new dimension in networking.A PON is a system that brings optical fiber cabling and signals to the end user employing multiple wavelengths in a single fiber to multiply the capacity without increasing the data rate thus offering better privacy and scalability because each Network Unit receives its on wavelength.WDM-PON is the next generation in development of access networks. The book presents a brief overview and benefits of WDM-PON over conventional PON technologies. It also focuses on various WDM-PON applications, advantages, disadvantages and its challenges . It illustrates the simulation of WDM- Passive Optical Network for different data formats, bit rates, signal input power and extinction ratio. I shall feel my labour amply rewarded if this book proves to be useful to graduate students as well as scientists and engineers involved in lightwave technology
Nowadays local access network technologies tend to take advantage of the potentially high data rate capabilities of fibre communication to deliver faster and more various services to end users than the traditional access networks, whilst the characteristics of current optical technologies impose several constraints and bottlenecks on the operations and deployment of all optical networks. This work aims to design an efficient control protocol for optical packet switched local area network, avoiding the limitations and challenges that optical technologies usually have, so that optical packet switching can be implemented in the near future with existing optical components.
This book contains a good literature survey of various mathematical models and routing & wavelengths assignment algorithms in WDM optical networks. Some of the new algorithms for optimization of blocking probability have aslo been covered. This book is good for researchers who are working on optical networks and advancements in fiber optics communication. Mathematical models covered in this book are simple and easy to implement. A good number of routing and wavelength assignment algorithms have also been covered in this book which can be used to reduce blocking probability of the optical network. This book can be very helpful to the research scholars.
This book focuses on various problems of the operation of a WDM optical packet ring: design, packet scheduling, delivered QoS and efficiency of optical transport. The relationship between these issues is shown and a range of tools for dimensioning and network control is proposed. This synchronous optical packet ring with multiple data channels and a single control channel has been studied by the ANR ECOFRAME (2007-2010). The stations of the ring have tunable transmitters and WDM fixed receivers. For a given traffic matrix, a cost of configuration incorporating costs of using wavelengths (data channels) and receivers is minimized by using Integer Linear Programming (ILP) models and heuristics. The complexity class of the problem has also been proved. Then, the performance evaluation study is performed by using the analytical and simulation tools. The optimal design case, from the point of view of cost and performance has been identified. It is shown that optimally dimensioned optical packet slotted ring can achieve a solid performance without the use of slot reservation mechanisms.
Relevant for computer systems and communications engineers as well as networking vendors. Explores the optical multicast wavelength division multiplexing (WDM) technology and the media access control (MAC) protocols that supports multicast traffic in local WDM networks. Presents a comprehensive and comparative study of different challenges faced in the design of multicast technique and schemes. Investigates design issues and considerations for flexible and scalable network architecture such as multicast wavelength assignment problem, transceivers tuning limitations, multicast scheduling algorithms, reconfiguration techniques, and survivability strategies. Provides a thorough analysis of the single-hop WDM optical network based on the broadcast-and-select with passive star coupler (PSC) system.
Revision with unchanged content. Research and development on optical networks generally and on Passive Optical Networks (PON) particularly have matured considerably. The exponential increase in the demand for bandwidth has exposed many challenges in the "last mile" that remains the bottleneck in broadband access networks. Currently, Ethernet PON has emerged as the most inexpensive panacea, providing more bandwidth than Cable Modems and Digital Subscriber Lines. Nevertheless, providing fair and efficient Quality of Service (QoS) has always been a major issue due to the un-deterministic nature of Time Division Multiple Access (TDMA) technology and the limited 1 Gbps channel speed that EPON relies on; unlike backbone networks that uses the Wavelength Division Multiplexing (WDM) technology. This book instruments these challenges and issues and offers effective solutions. More specifically, it presents an upgrade from a TDM-PON to a Hybrid TDM/WDM-PON and proposes and validates the first framework that enables for per-stream QoS protection in EPON using a new fair QoS scheduler. The book addresses professionals in optical and access networks. It is also directed towards researchers who would like to get a novel fragrance of EPONs.
Wireless local area networks (WLANs) have traditionally been used to transport only data, but are now being used to carry voice traffic as well as provided new combined voice and data services. Voice over WLANs also offers more flexibility than wired networks (changes to a WLAN don't require changes to installed wiring) and greater capacity than wired networks. This book provides a solid overview of voice over WLANs/VoIP (voice over internet protocol) technology, including voice coding, packet loss, delay and jitter, and echo control. It shows how to combine both WLAN and VoIP technology to create effective voice over WLAN systems. Gives complete details on integrating voice and data services on WLANs, including wide area networks. Explores quality of service (QoS) and security issues. Step-by-step descriptions of how to plan and implement voice over WLAN networks.
Residential users have a growing need for multiple groups of broadband services, such as video, fast internet or high-quality audio. And optical fibres can offer the physical infrastructure to create a fusion and convergence of the access network for next-generation access services. In this research field, the influence of most parameters that modify the frequency response of both silica-based multimode optical fibres and graded-inedx polymer optical fibres is theoretically and experimentally addressed. Furthermore, the increasing in-building networking feasibility can enhance the automation and integration of numerous optical sensor applications and systems. Related to this latter fact, an efficient multiplexing and sel-referencing scheme for optical fibre intensity sensors is demonstrated. A new approach for individually monitoring optical power loss of drop fibres in access Wavelength-Division-Multiplexing Passive Optical Networks (WDM-PON) is also reported. These WDM-PON topologies are considered to be the target architecture in the long-term for the next-generation access networks in Fibre-To-The-x (FTTx) deployments.
Transmission Control Protocol (TCP) is the dominant protocol in modern communication networks, within which the issues of reliability, data flow and congestion control must be handled efficiently. TCP provides a communication service at an intermediate level between an application program and the Internet Protocol (IP). With the evolution of Third Generation (3G) toward 4G wireless network, such as Long Term Evolution-Advanced (LTE-Advanced) standard, the use of TCP becoming more important for reliable end-to-end data delivery. As TCP was initially designed for wired networks, the LTE-Advanced network performance will degrade due to signal impairment and heavily congested links. Consequently, the traditional TCP versions such as Tahoe, Reno, Newreno, Sack, Fack, and Vegas, could not fulfil LTE-Advanced requirements to support huge number of user equipment’s that need wider channel bandwidth, low latency, and the enormous data stream transferred over this network. The objective of this book is to investigate the significant role of TCP over LTE and LTE-Advanced networks and to analysing the opportunities to enhance the TCP variants to run efficiently over these networks.
In this book, I’d like to present my scientific work that is focused on the research progress in the area of hybrid passive optical networks. My goal is to summarize in one place the research results produced by many researchers and at the same time to present an interactive simulation tool for configuring hybrid optical access networks with requirements for successful implementations in real network environment. This book is intended as a general reference for researches, professionals and students working in the field of broadband hybrid passive optical networks. Properties of technologies intended for next-generation passive optical networks together with motivations and reasons for development of hybrid passive optical networks are presented. In details, features and requirements for HPON networks are analyzed. Features of WDM/TDM-PON, SUCCESS HPON, SARDANA HPON and Long reach PON hybrid networks are described with an emphasis placed on the network architecture and possible evolution steps. An important part is dedicated to the traffic protection and restoration schemes. An environment of the HPON Network Configurator as the simulation tool is very particularly introduced.
The present access services like video on demand, live streaming, online gaming etc. require enormous amount of bandwidth and traditional digital subscriber line technology fails to meet up this requirement. The next generation networks, in particular, hybrid WDM-TDM Long-Reach Passive Optical Networks provide the required bandwidth and reduce the operational expenditure. Laser sources used at the Optical Network Units increase the cost due the extra equipment required for stabilizing the operating wavelength. To overcome this, a centralized source is installed at the Optical Line Terminal and the signal is reflected and intensity-modulated at the ONU, by using a special optical device Reflective Semiconductor Amplifier (RSOA), thus making the end receiver unit “colourless”. The analytical model for RSOA has been described in detailed in this book. The primary objective of this enitre work is to examine the feasibility of hybrid WDM-TDM LR-PON physical layer uplink setup consisting of reflective ONUs with due consideration to the BER performance in presence of realistic and non-ideal characteristics of optical and optoelectronic devices used in the setup.
There is an ever increasing need for bandwidth in the Internet and various other bandwidth hungry applications. This demand can be satisfied using optical WDM that allows the same fiber to carry many signals as long as each of these uses a different wavelength. WDM is a step towards furnishing the capabilities of the optical fiber which uses wavelength routing that is the networks ability to route a signal at intermediate nodes based on their wavelength.It has the ability to create a virtual topology upon the underlying physical topology of the network. The design of a virtual topology requires setting up of lightpaths which can traverse multiple links in the physical network and yet transmission is entirely optical without any opto-electronic conversion at the intermediate nodes.The potential of the virtual topology is dependent on the virtual topology design. The designing process is a complex problem.A designed virtual topology can be considered for various objective functions such as congestion control, delay minimization, hop length minimization, reducing the number of optical transceivers employed, minimizing the number of wavelengths utilised etc.