Optical WDM Networks: Principles and Practice / Edition 1

by Krishna M. Sivalingam, Suresh Subramaniam

Overview

Optical WDM networking technology is spearheading a bandwidth revolution in the networking infrastructure being developed for the next generation Internet. Rapid advances in optical components have enabled the transition from point-to-point WDM links to all-optical networking.
Optical WDM Networks: Principles and Practice presents some of the most important challenges facing the optical networking community, along with some suggested solutions. Earlier textbooks in optical networking have a narrower perspective, and rapidly advancing research has created the need for fresh and current information on problems and issues in the field. The volume editors and contributing authors have endeavoured to capture a substantial subset of the key problems and known solutions to these problems.
All of the chapters are original contributions from leading international researchers. The chapters address a wide variety of topics, including the state of the art in WDM technology, physical components that make up WDM fiber-optic networks, medium access prools, wavelength routed networks, optical access networks, network management, and performance evaluation of wavelength routing networks. The chapters also survey critical points in past research and tackle more recent problems.
Practitioners and network product engineers interested in current state-of-the-art information beyond textbook-type coverage, and graduate students commencing research in this area, will appreciate the concise - and pertinent - information presented herein.

Product Details

ISBN-13:	9781441949790
Publisher:	Springer US
Publication date:	12/07/2010
Series:	The Springer International Series in Engineering and Computer Science , #554
Edition description:	2002
Pages:	352
Product dimensions:	6.10(w) x 9.25(h) x 0.24(d)

Read an Excerpt

Chapter 1: Survey of State-of-the-Art

Introduction

We are moving towards a society which requires that we have access to information at our finger tips when we need it, where we need it, and in whatever format we need it. The information is provided to us through our global mesh of communication networks, whose current implementations, e.g., today's Internet and asynchronous transfer mode (ATM) networks, do not have the capacity to support the foreseeable bandwidth demands.

Fiber-optic technology can be considered our saviour for meeting our above need because of its potentially limitless capabilities [Mukherjee, 1997], [Cochrane, 1995]: huge bandwidth (nearly 50 terabits per second (Tbps)), low signal attenuation (as low as 0.2 dB/km), low signal distortion, low power requirement, low material usage, small space requirement, and low cost. Our challenge is to turn the promise of fiber optics to reality to meet our information networking demands of the next decade (and well into the next century!).

Thus, the basic premise of the subject on optical wavelength-division multiplexing (WDM) networks is that, as more and more users start to use our data networks, and as their usage patterns evolve to include more and more bandwidth-intensive networking applications such as data browsing on the world wide web (WWW), java applications, video conferencing, etc., there emerges an acute need for very high-bandwidth transport network facilities, whose capabilities are much beyond those that current high-speed (ATM) networks can provide. There is just not enough bandwidth in our networks today to support the exponential growth in user traffic!

Given that a single-mode fiber's potential bandwidth is nearly 50 Tbps, which is nearly four orders of magnitude higher than electronic data rates of a few gigabits per second (Gbps), every effort should be made to tap into this huge opto-electronic bandwidth mismatch. Realizing that the maximum rate at which an end-user, which can be a workstation or a gateway that interfaces with lower-speed subnetworks, can access the network is limited by electronic speed (to a few Gbps), the key in designing optical communication networks in order to exploit the fiber's huge bandwidth is to introduce concurrency among multiple user transmissions into the network architectures and protocols. In an optical communication network, this concurrency may be provided according to either wavelength or frequency [wavelength-division multiplexing (WDM)], time slots [time-division multiplexing (TDM)], or wave shape [spread spectrum, code-division multiplexing (CDM)].

Optical TDM and CDM are somewhat futuristic technologies today. Under (optical) TDM, each end-user should be able to synchronize to within one time slot. The optical TDM bit rate is the aggregate rate over all TDM channels in the system, while the optical CDM chip rate may be much higher than each user's data rate. As a result, both the TDM bit rate and the CDM chip rate may be much higher than electronic processing speed, i.e., some part of an end user's network interface must operate at a rate higher than electronic speed. Thus, TDM and CDM are relatively less attractive than WDM, since WDM unlike TDM or CDM has no such requirement.

Specifically, WDM is the current favorite multiplexing technology for optical communication networks since all of the end-user equipment needs to operate only at the bit rate of a WDM channel, which can be chosen arbitrarily, e.g., peak electronic processing speed. Hence, the major carriers today all devote significant effort to developing and applying WDM technologies in their businesses.

Wavelength-Division Multiplexing(WDM)

Wavelength-division multiplexing (WDM) is an approach that can exploit the huge opto-electronic bandwidth mismatch by requiring that each end-user's equipment operate only at electronic rate, but multiple WDM channels from different end-users may be multiplexed on the same fiber. Under WDM, the optical transmission spectrum (see Fig. 1.1) is carved up into a number of non-overlapping wavelength (or frequency) bands, with each wavelength supporting a single communication channel operating at whatever rate one desires, e.g., peak electronic speed. Thus, by allowing multiple WDM channels to coexist on a single fiber, one can tap into the huge fiber bandwidth, with the corresponding challenges being the design and development of appropriate network architectures, protocols, and algorithms. Also, WDM devices are easier to implement since, generally, all components in a WDM device need to operate only at electronic speed; as a result, several WDM devices are available in the marketplace today, and more are emerging.

Research and development on optical WDM networks have matured considerably over the past few years, and they seem to have suddenly taken on an explosive form, as evidenced by recent publications [Mukherjee, 1997; JSAC98, 1998; JLT96, 1996; JSAC96, 1996; JLT93, 1993; JSAC90, 1990; JHSN95, 1995] on this topic as well as overwhelming attendance and enthusiasm at the WDM workshops during recent conferences: Optical Fiber Communications conference and IEEE International Conference on Communications. A number of experimental prototypes have been and are currently being deployed and tested...

Table of Contents

Survey of State-of-the-art.- Optical Network Components.- Fiber, Lasers, Receivers, and Amplifiers.- Switches, Wavelength Routers, and Wavelength Converters.- Wavelength Routing Networks.- Design of Logical Topologies for Wavelength Routed Networks.- A Taxonomy of Switching Techniques.- WDM Networks with Limited or no Wavelength Conversion for Worst Case Traffic.- Broadcast Star Networks.- MAC Prools for WDM Networks — Survey and Summary.- Scheduling Algorithms for Unicast, Multicast, and Broadcast.- Design and Analysis of a Media Access Prool for Star Coupled WDM Networks with TT-TR Architecture.- A Multicasting Prool for Multichannel Local Optical Networks.- Performance Evaluation.- Blocking Performance of Wavelength-routing Networks.- Dynamic Wavelength Routing Techniques and their Performance Analyses.- Miscellaneous Topics.- Optical Access Networks for the Next Generation Internet.- Optical Network Management.- Hitless Switching in a Data-centric WDM Optical Network.- Optical WDM Networks: Future Vision.