Journal of High Speed Networks - Volume 4, issue 1

Authors: Bala, Krishna | Mukherjee, Biswanath

Article Type: Other

DOI: 10.3233/JHS-1995-4101

Citation: Journal of High Speed Networks, vol. 4, no. 1, pp. 1-3, 1995

Authors: Li, Victor O. K. | Willner, Alan E. | Dapkus, P. Daniel | Lee, Kuo-Chun | Norte, A. David | Park, Eugene | Shieh, William | Mathur, Atul

Article Type: Research Article

Abstract: This paper summarizes a proposal of research on all-optical networks submitted to the U.S. National Science Foundation in 1993. The objective is to explore the possible architectures, routing protocols, and system and device implementations for the metropolitan-area or wide-area wavelength-division-multiplexing (WDM) all-optical networks. The basic idea is to dramatically enhance the efficiency and throughput of such a WDM all-optical network by using wavelength conversion (or wavelength shifting) and by developing unique wavelength routing schemes which consider new models and requirements of all-optical networks. We will be conducting research on the intertwined networks, systems, and devices areas of photonics. In network …research, new network architectures and routing algorithms will be designed to incorporate wavelength conversions which allow messages to shift wavelengths. Also, rerouting algorithms will be developed to rearrange the routes of certain existing circuits to accommodate more connections. Furthermore, the use of erbium-doped fiber amplifiers (EDFAs) in WDM networks will be considered, and routing algorithms will be designed to reduce the performance degradation due to the spectral gain nonuniformity or the bandwidth limitation of EDFAs. In systems research, an experimental WDM node will be built to incorporate many aspects of the above network and routing schemes and to show what limitations exist in these systems. Both commercially available and unique novel state-of-the-art devices (to be fabricated ourselves) will be employed for the systems experiments. In device research, a novel integrated wavelength converter will be fabricated to shift one wavelength to several other possible wavelengths. This integrated photonic device will include a semiconductor amplifier where the conversion takes place, and a multiple-wavelength laser array which will provide the necessary reference wavelengths. Such a photonic integrated circuit device will significantly aid in the practical implementation of wavelength shifting at a WDM node. Show more

Keywords: All-Optical Networks, WDM Networks, Wavelength Routing, Wavelength Conversion, Optical Amplifiers, Optical Switching

DOI: 10.3233/JHS-1995-4102

Citation: Journal of High Speed Networks, vol. 4, no. 1, pp. 5-25, 1995

Authors: Zhang, Zhensheng | Guo, Duanyang | Acampora, Anthony

Article Type: Research Article

Abstract: In this paper, we present three logarithmically scalable routing algorithms for very large optical networks. The algorithms are based on a hierarchical approach. Each algorithm requires a different amount of information to be stored at each node, and results in a different efficiency. The network capacity provided by each algorithm is compared with that provided by the global shortest path algorithm (which is not scalable). It is found that the network capacities of the three algorithms are almost the same as that of the global shortest path algorithm. For fixed routing algorithms, we use an approximate analysis, appeared in the …literature, from which the blocking probability at a fixed network load can iterately be obtained (we use call blocking probability as our quality objective and compare network capacity by observing the difference in the offered load which produces the same blocking probability). The approximate analysis is validated through simulation and is found to be very accurate. Scalable, quasi-dynamic routing algorithms are also studied. Numerical results show that, when the node-capacity is equal to the capacity of a single wavelength and the bandwidth required per call is large (greater than 24% of the link capacity), the capacity provided by the quasi-dynamic routing algorithm is very close to that of an infinite capacity centralized switch (lowest possible call blocking caused exclusively by congestion on the finite capacity user input/output links, never by the switch fabric itself). In all the examples considered, the improvement of the quasi-dynamic routing algorithm over the fixed routing algorithm is significant. Show more

Keywords: Optical Networks, WDM, Scalable Routing Algorithms, Dynamic Routing, Blocking Probability

DOI: 10.3233/JHS-1995-4103

Citation: Journal of High Speed Networks, vol. 4, no. 1, pp. 27-40, 1995

Authors: Chan, Kai Choong | Cheng, Holden Ho Yuen | Liu, Hai Feng | Ahmed, Khawaja Aamer

Article Type: Research Article

Abstract: Optical solitons exploit the nonlinear nature of the refractive index of silica fibers to overcome the effects of group velocity dispersion (GVD). It is well established that the remarkable resilient properties of solitons stabilize them against perturbations to permit long distance transoceanic transmissions. This paper reviews the basic properties of fundamental solitons and their applications in both ultra high speed and wavelength-division-multiplexed communication systems. The unique properties of solitons can be advantageously used to realise pulse compression. By combining this with the ultrafast semiconductor laser technologies, soliton transmission over 100 Gbit/s is possible. Furthermore, the transparency between solitons of different …central wavelength in collisions makes solitons especially attractive in wavelength-division-multiplexed communication systems. Considerations in the practical implementation of solitons in communication systems are outlined and remedies to the fundamental problems encountered are described. The combination of soliton transmission and the application of solitons in wavelength-division-multiplexed communication systems provide a natural progression to expand the capacity of optical fibers. It is expected that future generations of transoceanic optical systems will support the propagation of solitons for high bit-rate communications. Show more

Keywords: Optical Fiber Communications, Optical Solitons, Wavelength Division Multiplexing, Short Pulses, High Speed, Long Distance, High Bit-Rate, Review

DOI: 10.3233/JHS-1995-4104

Citation: Journal of High Speed Networks, vol. 4, no. 1, pp. 41-59, 1995

Authors: Barry, Charles F. | Agrawal, Sanjay K. | Taranenko, Nina L. | Noronha, Ciro A. | Kazovsky, Leonid G.

Article Type: Research Article

Abstract: We report on the design of a distributed, small, fast packet switched network interface that provides electronic buffering and switching for the data channel in reconfigurable multi-Gbps WDM optical networks. The high-speed interface has been constructed and tested in one such WDM network, STARNET, which is based on a physical passive star topology and is intended for backbone applications in Campus Networks. A two-node experimental STARNET is being implemented at the Optical Communications Research Laboratory at Stanford University. The interface prototype was completed in September 1993; the printed circuit board version of the interface has been operational without modification since …January 1994. We have since developed software from the driver level to the applications layer. Show more

Keywords: Gigabit Networks, Optical Networks, Network Interface, Packet Switching, ATM, Real-Time, Performance Guarantees

DOI: 10.3233/JHS-1995-4105

Citation: Journal of High Speed Networks, vol. 4, no. 1, pp. 61-76, 1995

Authors: Grah, Adrian | Todd, Terence D.

Article Type: Research Article

Abstract: Recent advances in photonic amplification have re-motivated the use of ring and bus topologies in single-hop wavelength division-multiplexed (WDM) networks [1]. The use of WDM offers a significant increase in capacity over traditional single-channel networks. However, the parallel channel nature of these networks tends to complicate both the media access protocols and hardware requirements of the user stations, [1] and [2]. In this paper, four different WDM bus/ring networks are considered. All four have user station hardware designs with various reductions in the number of tapping points, number of transmitters and receivers and their tunability requirements. With each reduction …in hardware, protocol complexities and performance reductions are introduced. In all cases, dynamic packet-switched operation is achieved. The designs thus give an indication of the cost/performance tradeoffs which are possible as the amount of hardware is reduced at the user stations. Common to each of the designs is the use of a headend controller which attaches to each WDM channel. Media access is achieved through information provided by the controller. In the more hardware intensive designs, media access is achieved through a mini-slot contention mechanism [3]. The remaining designs rely on a hybrid opto-electronic request/allocation protocol motivated by DCCN [4]. Analytical models are presented which are validated through discrete-event simulations for each design. Show more

Keywords: Local Area Networks, Metropolitan Area Networks, Wavelength-Division-Multiplexing, Photonic Networks, Ring, Bus

DOI: 10.3233/JHS-1995-4106

Citation: Journal of High Speed Networks, vol. 4, no. 1, pp. 77-98, 1995

Authors: Yener, Bülent | Boult, Terrance E.

Article Type: Research Article

Abstract: This paper presents a new method for computing the lower bounds for multihop network design problems which is particularly well suited to optical networks. More specifically, given N stations each with d transceivers and pairwise average traffic values of the stations, the method provides a lower bound for the combined problem of finding optimum (i) allocation of wavelengths to the stations to determine a configuration, and (ii) routing of the traffic on this configuration while minimizing congestion – defined as the maximum flow assigned on any link. The lower bounds can be computed in time polynomial in the …network size. Consequently, the results in this work yield a tool which can be used in (i) evaluating the quality of heuristic design algorithms, and (ii) determining a termination criteria during minimization. The lower bound computation is based on first building flow trees to find a lower bound on the total flow, and then distributing the total flow over the links to minimize the congestion. Show more

Keywords: Multihop Lightwave Networks, Network Optimization, Lower Bounds, Algorithms

DOI: 10.3233/JHS-1995-4107

Citation: Journal of High Speed Networks, vol. 4, no. 1, pp. 99-113, 1995