Journal of High Speed Networks - Volume 10, issue 1

Authors: Joshi, Anupam | Krishna, Arvind

Article Type: Other

Citation: Journal of High Speed Networks, vol. 10, no. 1, pp. 1-6, 2001

Authors: Eklund, Carl | Mäkinen, Jarmo T. | Ojanperä, Tero | Pihlaja, Juha

Article Type: Research Article

Abstract: Broadband Wireless Access (BWA) is moving into the IP era. New open interoperability standards for millimeter wave point‐to‐multipoint (PMP) radios, IEEE802.16 and HiperAccess, are being developed enabling low cost, mass‐market systems. In this paper PMP standardization, regulation, service requirements and system design will be discussed.

Citation: Journal of High Speed Networks, vol. 10, no. 1, pp. 7-17, 2001

Authors: Gao, Xia | Nandagopal, Thyagarajan | Bharghavan, Vaduvur

Article Type: Research Article

Abstract: The increasing number of wireless data users and the deployment of broadband wireless networks have brought the issue of providing fair channel access to the forefront. Wireless fair scheduling algorithms must deal with unique domain‐specific issues such as location‐dependent and bursty channel error. In the past, a number of scheduling disciplines have been proposed for approximating fluid fair queueing in wireless channels, but using only the ARQ‐based link‐layer retransmit model (Bhagwat et al., in: IEEE INFOCOM, 1996; Lu et al., in: ACM SIGCOMM, 1997; Ng et al., in: IEEE INFOCOM, 1998; Lu et al., WINET 6, 2000, pp. 323–343; Nandagopal …et al., in: ACM MOBICOM, 1999). In this work, we generalize past work in three key ways: (a) we use the notion of ‘utility‐based’ fair scheduling, wherein the goal of the scheduler is to serve flows in a way that maximizes the aggregate utility of the system, (b) we combine the techniques of FEC and ARQ in a generalized framework in which different scheduling disciplines can be realized by mixing and matching component algorithms within the framework, and (c) we support the notion of ‘application level fairness’ when flows see different channel error probabilities. Specifically, we explore the combination of adaptive FEC and ARQ‐based schemes within the utility‐based wireless fair scheduling paradigm. We show through simulation and analysis that this combination enables the scheduling disciplines to optimize the aggregate system utility and achieve application level fairness, while handling varying channel errors effectively. Show more

Citation: Journal of High Speed Networks, vol. 10, no. 1, pp. 19-36, 2001

Authors: Toh, C.‐K. | Tsai, Wei K.

Article Type: Research Article

Abstract: This paper highlights the differences in Quality of Service (QoS) definitions for wired high speed ATM networks and wireless broadband ATM networks. In particular, we highlight the issues behind QoS mapping and discuss several frameworks for QoS adaptation in wireless broadband networks. We explain the need for end‐to‐end adaptation and reveal how such adaptation occurs during mobile handoffs. The instability and sensitivity problems occurred as a result of frequent handoffs and QoS adaptation are explained and related to control theory. We provide several control approaches that will ensure stability in the network under such circumstances. It is important that future …broadband wireless networks must be able to offer network services and QoS assurance without causing network instability. This paper, therefore, reveal possible approaches to be considered in the design of future broadband wireless systems. Show more

Citation: Journal of High Speed Networks, vol. 10, no. 1, pp. 37-58, 2001

Authors: Kumar, Apurva | Ramachandran, Lakshmi | Shorey, Rajeev

Article Type: Research Article

Abstract: Bluetooth is a promising new technology for short range, low power, low cost, pico‐cellular wireless connectivity between mobile devices. Efficient clustering or topology construction algorithms play a very important role in the fast connection establishment of such networks. The performance of these algorithms is mainly dependent on the device discovery time, i.e., the time taken by a node to discover and to connect to another node in its radio range, as well as the protocols used for organizing them into the required topology. We define metrics for device discovery performance and evaluate them by simulating the inquiry routine in Bluetooth …for various ad‐hoc scenarios. We indicate the scenario where device discovery in Bluetooth can become a bottleneck. We then describe some recent results on topology construction algorithms for Bluetooth. Data applications running over Bluetooth such as http, ftp and real audio will need transport layer protocols such as TCP and UDP to send packets over the wireless links. We propose and compare a number of MAC scheduling algorithms with the aim of improving the performance of asynchronous data traffic over a Bluetooth piconet that supports multiple active slaves. We study how the presence of circuit‐switched voice impacts the performance of data traffic. Show more

Keywords: Bluetooth technology, scatternet, piconet, device discovery, inquiry, paging, scheduling, cluster, topology, Media Access Control (MAC), Time Division Duplex (TDD), TCP, IP, UDP, utilization, throughput, end‐to‐end delays

Citation: Journal of High Speed Networks, vol. 10, no. 1, pp. 59-76, 2001