Request pdf wavelength conversion in optical networks in many models of. Dwdm fundamentals, components, and applications jeanpierre laude. In many models of optical routing, we are given a set of communication paths in a network, and we must assign a wavelength to each path so that paths sharing an edge receive different wavelengths. Pdf wavelength conversion and wavelength assignment are key determinants. The goal is to assign as few wavelengths as possible in order to make as efficient use as possible of the optical bandwidth.
Wavelength converters in optical networks by k r venugopal. Optimizing the placement of wavelength converters in wdm. Types of wavelength converters a optoelectronic approach. The wavelength in air is only so slightly smaller that this deviation is not relevant for most applications. Wavelength conversion using nonlinear effects in optical. Fujitsu and fraunhofer hhi develop firstever simultaneous. As the name suggests wavelength converter converts optical signal with one wavelength to the other optical signal. Bertsekas 2 abstract the problem of routing and wavelength assignment rwa is critically important for increasing the e. Routing and wavelength assignment in optical networks. Allopticaldpskwavelengthconverterbasedonmziwithintegratedsoasandphaseshifters. In this paper, an enhanced analytical model is proposed to evaluate the blocking performances in topology network and to improve the performances of reduction of blocking probability.
In this paper, we investigate the relative performance advantage offered by wavelength converter placement and wavelength assignment. Routing and wavelength assignment in optical networks 1 by asuman e. However, with the development of optical networks and the use of dense wavelength division multiplexing dwdm technology, a new and probably, a very crucial milestone is being reached in network evolution. Since each optical signal is sent along a specified path and not broadcast to all nodes in the network, the power requirement of such a network is lower than that of a broadcastandselect network. Optimizing the placement of wavelength converters in wdm optical networks author. The synchronous ops node architecture, with a hybrid shared wavelength conversion hswc scheme based on shared per output fiber and shared per node wavelength conversion, is put forward to reduce the packet loss probability in this paper. Optical wavelength converters are of four types based on their input and output wavelength handling limits. This alert has been successfully added and will be sent to. Wavelength conversion is an efficient way to improve the optical packet blocking performance for alloptical packet switching networks. Wavelength conversion in optical networks request pdf. Wavelength conversion placement and wavelength assignment. In fiberoptic communications, wavelengthdivision multiplexing wdm is a technology which multiplexes a number of optical carrier signals onto a single optical fiber by using different wavelengths i. The most fully equipped nodes in future optical networks will include spatial switching and wavelength conversion to ensure the largest degree of flexibility and best performance with regard to.
Alloptical dpsk wavelength converter based onmzi soas. Wavelength conversion an overview sciencedirect topics. Some promising alloptical switching networks asns, such as optical burstswitched obs 1 and optical packetswitched networks, have been proposed to meet this need. Benefits of wavelength translation in alloptical clearchannel networks. Lukac z and tkalic m benefits of wavelength conversion in optical wdm mesh networks with dynamic routing proceedings of the 24th iasted international conference on parallel and distributed computing and networks, 117122.
Fiber capacity crunch concerns are driving optical networking toward a. This paper proposes optical wavelength division multiplexed wdm networks with limited wavelength conversion that can efficiently support lightpaths connections between nodes. International journal of scientific and research publications, volume 4, issue 1, january 2014 keywords. The accuracies to which optical atomic frequencies have been determined relative to primary cs frequency standards are illustrated in. All optical wavelength conversion by soas in a machzender configuration.
The analysis of wdm wavelengthdivision multiplexing optical network is essential to have the routed wavelength blocking probability with the conversion of wavelength using techniques. Ifip tc6 second international working conference on optical network design and modelling ondm98 february 911, 1998 rome, italy by marchis, giancarlo. A novel node architecture for alloptical switching networks. Alloptical networks with sparse wavelength conversion ieeeacm.
Wavelength converters in optical networks, 1e k r venugopal 2008 180 pp hardback isbn. Iit kanpur 15 introduction to optical networks optical tdma, cdma implementations need very short pulses can be generated by mode locked. Optical clocks are now a reality and are beginning to perform at levels that eclipse previous nonoptical technologies. Optical networks based on wavelengthdivision multiplexing wdm tech nology offer the promise to satisfy the bandwidth requirements of the inter net infrastructure, and provide a scalable solution to support the bandwidth needs of future applications in the local and wide areas. Asns use optical switches rather than opticalelectricaloptical conversion to achieve transparent. Interferometry applications in alloptical communications. That is, wavelength conversion allows a lightpath to. Wavelength conversion helps improve the performance of wavelength division multiplexed wdm optical networks that employ wavelength routing.
Wavelengthrouted networks the wavelength of the optical signal and the fiber it is using determine the subsequent path used by the signal. Advances in optical amplifiers presents up to date results on amplifier performance, along with explanations of their relevance, from leading researchers in the field. Most chapters of this bock are focused on various issues related to wavelengthrouted networks, namely, routing and wavelengthassignment, con trol and management, fault management, and wavelengthconverter placement. Multiple wavelengthdivision mul tiplexed channels can be operated on a single. Optical wavelength converter optical band conversion l. Traditionally, wavelength conversion occurs outside the optical fiber, in electronic devices called modulators, explains robert boyd, professor of optics at the university of rochester. With wavelength converters, this signal could be optically switched to any port pj on some other wavelength. Mukherjee,wavelength conversion in wdm networking,ieee selected areas in communications sept 1998. In this framework, this chapter presents a study on alloptical. All optical signal processing technologies in optical fiber.
Coherent communications, using the amplitude and phase of the optical wave, resurface as one of the transmission methods to increase the effective bandwidth of optical channels. Wavelength conversion has been acknowledged as one of the most significant optical processing functions. Wavelength division multiplexing wdm, optical networks, routing and wavelength assignment rwa, virtual topology design, optical multicast. But the signal might go through eo and oe conversion. The most fully equipped nodes in future optical networks will include spatial switching and wavelength conversion to ensure the largest degree of flexibility and best performance with regard to blocking of paths in the network. Ramaswami, multiwavelength lightwave networks for computer communication, ieee commun. The goal is to assign as few wavelengths as possible, in order to make as ecient use as possible of the optical bandwidth. Routing and wavelength assignment in optical wdm networks.
In a waveleng routed network, an optical channel, referred to as a lightpath, is set up between two network nodes. Ultrahigh data rate all optical wavelength conversion is an enabling technology for providing wavelength flexibility, increasing the capacity of photonics networks and enhancing optimized all optical routing and switching. In oxcs without a wavelength conversion capability, an incoming signal at port pi on wavelength can be optically. Two objective functions, namely, minimizing the average blocking probability and minimizing the maximum. Pdf wavelength conversion placement and wavelength. Wavelength converters placement in optical networks using. Research and development on optical wavelengthdivision multiplexing wdm networks have matured considerably. Unlike broadcastandselect networks, wavelengthrouting networks offer the advantages of wavelength reuse and scalability and are thus suitable for widearea networks wans we study the effects of topological connectivity and wavelength conversion in circuitswitched alloptical wavelengthrouting networks. Chapter 4 deals with wavelength rerouting algorithms to improve wavelength channel utilization. Wavelength conversion allows a clear optical channel to be carried on di erent wavelengths on di erent physical links. Wavelength converters placement in optical networks using bee colony optimization. Unlike broadcastandselect networks, wavelengthrouting networks offer the advantages of wavelength reuse and scalability and are thus suitable for widea. Optoelectronic repeaters can have a use in optical networks, complementing or replacing alloptical solutions. These types of converters are widely used in wdm networks.
Analysis on placement of wavelength converters in all optical wdm network. Switches, wavelength routers, and wavelength converters. Converting light wavelengths within fiber mit technology. Science and technology, general algorithms models artificial intelligence bees electric converters electric current converters fiber optic equipment fiber optic networks fiber optics equipment and supplies frequency division multiplexing. Wavelength conversion in wdm networking unl digital commons. This technique enables bidirectional communications over one strand of fiber, as well as multiplication of capacity the term wdm is commonly applied to an optical. Citeseerx wavelength conversion in optical networks. Business electronics industry fiber optic networks semiconductor industry. Blocking probability in alloptical wdm network using imca. It results in a high blocking factor call along the path and high latency. Each lightpath follows a route in a network and must be assigned a channel on each link along the.
Analysis on placement of wavelength converters in all optical wdm network agarwal, rupali, srivastava, neelam on. In this scenario alloptical conversion appears to be very advantageous more then for conventional amplitude shift keying. The inability of the optical switch to perform wavelength conversion has yielded a routing problem. This technology can efficiently utilize the enormous bandwidth of the optical fiber and has been able to meet the emerging integrated demands of the communication. Abstract wavelength conversion has been proposed for use in wavelengthdivision multiplexed networks to improve ef. The need of wavelength conversion in alloptical networks. Generally, the refractive index depends on the optical frequency. The goal is to assign as few wavelengths as possible in order to. A wdm optical system using a diffraction grating is completely passive, unlike electrical fdm, and thus is highly reliable. Recent research has also concentrated on wavelength conversion, switching, demultiplexing in the time domain and other enhanced functions. Wavelength conversion, lightpath, optical networks, wavelength continuity,wavelengthdivision multiplexing wdm.
We discussed wavelength conversion in chapter 7, specifically with reference to oxcs. Wavelength conversion placement in wdm mesh optical networks. Wavelength conversion techniques in optical networks. A novel contention resolution scheme of hybrid shared. Ultrahigh data rate alloptical wavelength conversion is an enabling technology for providing wavelength flexibility, increasing the capacity of photonics networks and enhancing optimized alloptical routing and switching. The explosion in the volume of electronic communication has resulted in an acute need for highperformance networks. Wavelength conversion in optical networks sciencedirect. The incompatibility of optical devices has violated the algorithms of path determination. Wavelengthrouted optical networks, ieeeacm transactions.
Throughout the years, the expanded search and flow of information led to an expansion of traffic intensity in todays optical communication systems. Given the physical network structure and the required connections, the. In many models of optical routing, we are given a set of communication paths in a network, and we must assign a wavelength to each path so that paths sharing an edge receive dierent wavelengths. Wavelength conversion and wavelength assignment are key determinants of the blocking performance of wavelengthrouting wdm networks. Given any network of arbitrary topology, the aim is to see if one can achieve the wavelength conversion optimal performance by using wavelength reassignment techniques in no conversion networks. Wavelength converters in optical networks deals with the third generation networks that use wavelength division multiplexing wdm, wavelength routed optical networking technology. Wavelengthrouted optical networks the university of texas at dallas.
Wavelength switched optical network wson is a type of telecommunications network. In transparent networks wavelength conversion turns out to be the key to overcome wavelength contention issues 2. The data plane comprises wavelengthdivision multiplexing wdm fiber links connecting optical crossconnect oxcs through a comb of several tens of wavelength channels, with typical data rates of 10 or 40 gbits. Using a graphtheoretical approach, we extend birmans model see ieee jsacjlt special i on optical networks, vol. Rp photonics encyclopedia wavelength, light, wavenumber. Citeseerx document details isaac councill, lee giles, pradeep teregowda. This tutorial will address all of these questions and explain the technologies, architectures, and market trends for emerging optical networks. Alloptical networks with sparse wavelength conversion ieee xplore. In this paper, we address the problem of optimally placing a limited number of wavelength converters in mesh topologies. Wavelength conversion in optical networks proceedings of.
Book overview wdm technology and issues in wdm optical. Fujitsu and fraunhofer hhi develop firstever simultaneous wavelength conversion technology with no wavelength restriction in nextgeneration optical networks. While optics and electronics should be used appropriately for transmission and switching hardware, note that intelligence in any network comes from software, for network control, management, signaling, traffic engineering, network planning, etc. Kleinburg99 jon kleinburg and amit kumar,wavelength conversion in optical networks,acmsiam on discrete algorithms, 1999 ramamurthy98 b. Wavelength interchange will become an important function in optical networks. This study highlights systems challenges and performance issues. Wavelength division multiplexing wdm technology and. Wavelength converter in optical wdm networks using evolutionary algorithm. This kind of wavelength conversion is called full wavelength conversion, and a node capable of full wavelength conversion can change the wavelength of an incoming lightpath to any of the outgoing. In wavelengthrouted wdm networks, optical channels, which are referred to as lightpaths, are set up between wdm terminals.