Benchmarking and viability assessment of optical packet switching for metro networks

Optical packet switching (OPS) has been proposed as a strong candidate for future metro networks. This paper assesses the viability of an OPS-based ring architecture as proposed within the research project DAVID (Data And Voice Integration on DWDM), funded by the European Commission through the Information Society Technologies (IST) framework. Its feasibility is discussed from a physical-layer point of view, and its limitations in size are explored. Through dimensioning studies, we show that the proposed OPS architecture is competitive with respect to alternative metropolitan area network (MAN) approaches, including synchronous digital hierarchy, resilient packet rings (RPR), and star-based Ethernet. Finally, the proposed OPS architectures are discussed from a logical performance point of view, and a high-quality scheduling algorithm to control the packet-switching operations in the rings is explained

Coherence-Multiplexed Optical RF Feeder Networks

An optical RF feeding system for wireless access is proposed, in which the radio access points are distinguished by means of coherence multiplexing (CM). CM is a rather unknown and potentially inexpensive optical code division multiple access technique, which is particularly suitable for relatively short-range applications with moderate transmission bandwidth requirements. Subcarrier multiplexing (SCM) can possibly be used on top of CM, either as single-channel or multichannel SCM. The performances of the resulting distribution networks are analyzed, incorporating the effect of chromatic dispersion, optical beat noise, shot noise, thermal noise, and—in the case of multichannel SCM—intermodulation distortion. The results of the IEEE 802.11b standard for wireless LAN.\u

Quantum Metropolitan Optical Network based on Wavelength Division Multiplexing

Quantum Key Distribution (QKD) is maturing quickly. However, the current approaches to its application in optical networks make it an expensive technology. QKD networks deployed to date are designed as a collection of point-to-point, dedicated QKD links where non-neighboring nodes communicate using the trusted repeater paradigm. We propose a novel optical network model in which QKD systems share the communication infrastructure by wavelength multiplexing their quantum and classical signals. The routing is done using optical components within a metropolitan area which allows for a dynamically any-to-any communication scheme. Moreover, it resembles a commercial telecom network, takes advantage of existing infrastructure and utilizes commercial components, allowing for an easy, cost-effective and reliable deployment.Comment: 23 pages, 8 figure

A multicast overlay scheme for wavelength division multiplexed passive optical networks.

Zhang, Yin.Thesis submitted in: December 2008.Thesis (M.Phil.)--Chinese University of Hong Kong, 2009.Includes bibliographical references (leaves 56-60).Abstracts in English and Chinese.Chapter Chapter 1 --- Introduction --- p.1Chapter 1.1 --- Telecommunications network hierarchy --- p.2Chapter 1.2 --- PON architectures for access networks --- p.4Chapter 1.2.1 --- TDM-PON --- p.5Chapter 1.2.2 --- WDM-PON --- p.7Chapter 1.3 --- Data delivery mode in WDM-PON --- p.8Chapter 1.3.1 --- Point-to-point --- p.8Chapter 1.3.2 --- Broadcast --- p.9Chapter 1.3.3 --- Multicast --- p.10Chapter 1.4 --- Motivation of this thesis --- p.10Chapter 1.5 --- Outline of this thesis --- p.13Chapter Chapter 2 --- Previous Multicast Architectures in WDM-PON --- p.14Chapter 2.1 --- Introduction --- p.15Chapter 2.2 --- Previous WDM-PON architectures with multicast capability --- p.15Chapter 2.2.1 --- Subcarrier multiplexing --- p.16Chapter 2.2.2 --- All-optical based multicast enabled architecture --- p.18Chapter 2.3 --- Summary --- p.21Chapter Chapter 3 --- A Multicast enabled WDM-PON Architecture Using ASK-DPSK Orthogonal Modulation --- p.23Chapter 3.1 --- Introduction --- p.24Chapter 3.2 --- System architecture --- p.25Chapter 3.3 --- Experimental Demonstration --- p.27Chapter 3.4 --- Discussion --- p.31Chapter 3.5 --- Summary --- p.36Chapter Chapter 4 --- A WG filtering and its suppression in quaternary ASK-DPSK based multicast enabled WDM-PON --- p.37Chapter 4.1 --- Introduction --- p.38Chapter 4.2 --- Principle of narrowband filtering --- p.38Chapter 4.3 --- Simulation model --- p.40Chapter 4.4 --- Simulation results and discussion --- p.42Chapter 4.4.1 --- Different extinction ratios --- p.43Chapter 4.4.2 --- Different AWG filter shape and bandwidth --- p.47Chapter 4.5 --- Summary --- p.50Chapter Chapter 5 --- Summary and Future Works --- p.51Chapter 5.1 --- Summary of the thesis --- p.52Chapter 5.2 --- Future works --- p.53List of Publications --- p.55BIBLIOGRAPHY --- p.5

Characterization of wavelength tunable lasers for use in wavelength packet switched networks

The telecom industry's greatest challenge, and the optical systems and components vendors' biggest opportunity is enabling providers to expand their data services. The solution lies in making optical networks more responsive to customer needs, i.e., making them more rapidly adaptable. One possible technique to achieve this is to employ wavelength tunable optical transmitters. The importance of tunability grows greater every year, as the average number of channels deployed on DWDM platforms increases. By deploying tunable lasers it is much easier to facilitate forecasting, planning and last minute changes in the network. This technology provides with solution for inventory reduction. It also offers solution for fast switching at packet level. The conducted research activities of the project was divided in two work packages: 1. Full static characterization-the laser used in the experiment was a butterfly-packaged Sampled Grating DBR laser with four electrically tunable sections. LabView programme was developed for distant control of the equipment and the laser itself. The parameters required for creating a look-up table with the exact currents for the four sections of the laser, namely wavelength, side mode suppression ratio and output power, were transferred to tables. Based on those tables the currents were defined for each of the 96 different accessible channels. The channel allocation is based on the 50 GHz spacing grid. A detailed analysis of the tuning mechanisms is provided. 2. Dynamic characterization and BER performance in wavelength packet switched WDM systems-a commercially available module was used supplied with the software package for controlling the wavelength channels and setting the laser to switch between any accessible channel. The laser is DBR laser without SOA integration so the dynamic tunability can be investigated. As the switching in the nanosecond regime is executed in the electrical domain, analysis of the switching parameters concerning the electrical circuit as well as laser structure is provided. The actual switching time was defined. The degradation in system performance due to spurious wavelength signals emitted from the tunable module during the switching event and their interference with other active channels was demonstrated by examining the presence of an error floor in the BER rate against received power measurements