Wave Division Multiplexing Research Articles

Sprint long distance network survivability: today and tomorrow

The high reliability exhibited by the Sprint long distance network is the result of many interrelated factors. The network utilizes robust architectures, systems, and equipment to provide a reliable transport infrastructure. Redundant equipment, conservative synchronization, protected power, and other factors combine to form a dependable foundation. New architectures and systems are under development to meet the changing demands of customers. This article summarizes Sprint's current network reliability, and emerging demands and technology, and presents possible directions for the future Sprint network. Sprint selected the SONET four-fiber bidirectional line switched ring (4F BLSR) architecture for the vast majority of its transport network architecture. A 4F BLSR architecture requires four fibers, or four optical wavelengths of wave division multiplexing (WDM), to accommodate a work and protect path in each direction around a ring of network elements or add-drop multiplexers (ADMs).

Wave-division multiplexing in the Sprint long distance network

The deployment of wave-division multiplexing (WDM) systems in the long distance network has dramatically increased the usable bandwidth of the embedded fiber optic cable. This article documents the utilization of WDM equipment in the Sprint long distance network. Many of the factors affecting the deployment of WDM systems are discussed from the selection and installation of the fiber optic cable in the 1980s to the current bandwidth demand. The future of WDM systems, network architecture, and the emerging optical layer are briefly addressed.

IP routers: new tool for gigabit networking

IP routing continues to receive much attention from the research and vendor communities. Its primary function-forwarding packets between networks-must keep pace with the demands of the exponentially growing end user population. It must accommodate attachment of gigabit data link technologies such as ATM, packet Sonet, Gigabit Ethernet, and dense wave division multiplexing, and fill those links at full capacity. As network providers introduce new services supporting multicast, QoS, voice, and security, IP routing-and more specifically the IP forwarding function-will be called upon to analyze additional packet information at gigabit rates to determine how each packet should be handled. Performing these new functions while maintaining parity with the advances in available bandwidth will present an interesting challenge for the forwarding capabilities of IP routers. Indeed, for the Internet to scale, we must scale all dimensions of the IP routing process.

Simulative study on the performance improvement of conflict resolution schemes in Manhattan Street Network

A simple node structure is essential in the design of multi-hop wave division multiplexing (WDM) networks to process packets immediately, when it acts in a high speed environment running at over 1 Gbps, and an effective routing mechanism is required to improve network performance. In this paper, we compare the performance of deflection routing with that of store-and-forward routing in the Manhattan Street Network (MSN), which is one of the typical multi-hop WDM networks. We also propose three conflict resolution schemes for the deflection routing and compare their performances, including the existing random selection scheme, which does not strictly adopt the conflict resolution mechanism. The results show that all the proposed schemes lead to substantial performance improvement over the random selection scheme; in particular, the scheme which prefers the packet with the minimum distance to the destination presents the best performance.

Analysis and optimization of transmission schedules for single-hop WDM networks

Considers single-hop lightwave networks with stations interconnected using wave division multiplexing. The stations are equipped with tunable transmitters and/or receivers. A predefined, wavelength-time oriented schedule specifies the slots and the wavelengths on which communication between any two pairs of stations is allowed to take place. The authors define a wide variety of schedules and develop a general framework for analyzing their throughput performance for any number of available wavelengths, any tunability characteristics, and general (potentially nonuniform) traffic patterns. They then consider the optimization of schedules given the traffic requirements and present optimization heuristics that give near-optimal results. They also investigate how the number of available wavelengths (channels) affects the system throughput, and develop techniques to efficiently share the available channels among the network stations. As a result, they obtain systems that are easy to scale while having very good performance.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>

Comparing Optical Packet Switching And Optical Burst Switching

The switching is an important part of the telecommunication networks over the years for transferring and handling voice and data through the traditional switching nodes existing in the telecommunication networks. Various developments were seen in the recent years which resulted in increasing data transfer capabilities of the transmission networks all over the world, however the switching speed and techniques are still remained unchanged in most of the cases that neither match the data transfer capacities nor the expanding demand of the networks in the near future. Some switching technologies are still in the developing stage, of them two are more obvious: Optical Packet Switching (OPS) and Optical Burst Switching (OBS). In this paper, I tried to compare different paradigm of these two main developments, keeping in mind that the OPS would see rapid development in the near future than the OBS, though OBS would the ultimate solution of switching for the bulk volume of telephone and data traffic Keywords: Optical Packet Switching; Optical Burst Switching; Bulk Volume; Data Traffic; Wavedivision Multiplexing DOI: http://dx.doi.org/10.3329/diujst.v6i2.9342 DIUJST 2011; 6(2): 22-32