Mobile Ad Hoc Networking Editorial
Post on 02-Aug-2016
Cluster Computing 5, 115116, 2002 2002 Kluwer Academic Publishers. Manufactured in The Netherlands.
Mobile Ad Hoc NetworkingEditorial
Mobile ad hoc networks are multi-hop wireless networks. Wireless communications and the lack of fixed infrastructuregenerate new research problems compared with fixed multi-hop networks:
Dynamic topologies. Because nodes can move arbitrarily, the network topology, which is typically multi-hop, can changerandomly and rapidly;
Bandwidth-constrained, variable capacity, possibly asymmetric links. Wireless links will continue to have significantlylower capacity than wired links and hence congestion is more problematic;
Energy-constrained operation. Some, or all nodes in a mobile ad hoc network may rely on batteries for energy. For thesenodes, power conservation is a critical design criterion;
Wireless vulnerabilities and limited physical security. Mobile wireless networks are generally more prone to informationand physical security threats than are fixed, hardwired nets.
Research on mobile ad hoc networks spans among several layers of a network architecture, ranging from physical layerissues up to transport and application aspects. However, most of ongoing research activities on MANET focus mainly onnetwork technologies and routing layer aspects. Network technologies for single-hop wireless LANs (WLANs) are becomingto appear on the market. Bluetooth technology is an open specification (supported by several hundreds of IT companies) forwireless communication of data and voice. The IEEE 802.11 standard is a good platform to implement a one level multi-hop architecture because of its extreme simplicity. HiperLAN is a family of standards for wireless LANs promoted by theEuropean Telecommunications Standards Institute (ETSI). Soon, mobile ad hoc networks that cover areas of several squarekilometres could be built from WLAN technologies such as IEEE 802.11. Furthermore, wireless-network technologies arethe building blocks to construct multi-hop mobile ad hoc networks. In the IETF, the Mobile Ad hoc NETwork (MANET)working group was set up for developing and evolving mobile ad hoc network routing specification(s) and introduce them tothe Internet Standards track. The goal is to support networks scaling up to hundreds of routers. The step toward a large network(larger than thousand nodes) consisting of nodes with limited resources is not straightforward and presents many challengesthat are still to be solved in areas such as: high-capacity wireless technologies, configuration management, addressing, routing,location management, interoperability, and security.
The special issue presents eight papers dealing with the single-hop WLAN technologies, location and routing in multi-hopnetworks.
The first set of three papers deals with Bluetooth, IEEE 802.11, and HiperLAN/2, and addresses the MAC-layer researchissues.
The paper by R. Bruno, M. Conti and E. Gregori focuses on the Bluetooth technology. This is the emerging technologyfor constructing Wireless Personal Area Networks (WPANs), i.e., ad hoc networks with a radius of 10 m. The paper presentsa survey of this technology, and a simulative analysis of its performance. Furthermore, the authors propose and evaluate ascheduling algorithm for a Bluetooth WPAN.
The paper by V.M. Vishnevsky and A.I. Lyakhov studies the performance of the IEEE 802.11 standard for Wireless LANs.The authors focus on the fundamental access method, i.e., the Distributed Coordination Function, and present an analyticalmethod that generalizes the existing IEEE 802.11 models. The analytical model is used to study the IEEE 802.11 saturationthroughput.
E. Mingozzi analyzes the HiperLAN/2 standard. HiperLAN/2 is a new ETSI standard for high-speed WLANs. HiperLAN/2data rates are in the range from 6 up to 54 Mbits/s. This paper introduces the basic features of HiperLAN/2 and, via simulation,investigates the performance of its MAC protocol. The performance analysis focuses on the protocol ability to support bothdelay-sensitive applications and Web traffic.
The second set of papers deals with location and routing in multi-hop networks.S. Capkun, M. Hamdi and J.-P. Hubaux present a completely self-organized positioning algorithm for mobile ad hoc
networks that does not need any a-priori position information, e.g., GPS. Specifically, the algorithm exploits the signal strengthbetween any pair of neighboring nodes to approximate their distance from which a triangulation algorithm determines the nodepositions. Despite the distance measurement errors and the motion of the nodes, the algorithm provides sufficiently accuratelocation information to support basic network functions.
116 CONTI AND GIORDANO
S. Datta, I. Stojmenovic and J. Wu deal with distributed routing algorithms for wireless networks, based on location in-formation. Specifically, the authors focus on the GFG algorithm and propose to improve its performance by using (i) theinternal nodes delivery and (ii) a shortcut procedure. A performance study shows the effectiveness of the authors approach.Improvements make the GFG close to the shortest path algorithm performance.
J.E. Wieselthier, G.D. Nguyen and A. Ephremides propose and evaluate energy-efficient broadcasting and multicastingschemes for infrastructure-less wireless networks. The novel aspect of the proposed schemes is the node-based view of theproblem. Specifically, the authors approach takes jointly into account two resource limitations: (i) the finite number oftransceivers at each node, and (ii) the finite number of the available orthogonal channels. A performance comparison showsthat the node-based approach provides better performance than the classical link-based schemes.
M. Chatterjee, S.K. Das and D. Turgut propose an on-demand distributed clustering algorithm for multi-hop ad hoc net-works. Clusterhead election is non-periodic, invoked on demand, and it is aimed to reduce the computation and communicationcosts. Simulation experiments show that the proposed algorithm is flexible and performs better than existing ones.
L. Blazevic, S. Giordano and J.-Y. Le Boudec consider the problem of routing in a wide area mobile ad hoc network. Theypropose a routing scheme that is a combination of two protocols: Terminode Local Routing (TLR) and Terminode RemoteRouting (TRR). TLR and TRR are used to route packets to close and remote destinations, respectively. The resulting algorithmis simple, highly scalable and dynamic. A simulative study shows the effectiveness of the proposed routing scheme.
We wish to take this opportunity to thank all the authors for their submissions and all the referees for the time and effort theyspent to review each paper in a professional way.
Marco Conti Silvia GiordanoIstituto CNUCE Communication Systems DepartmentConsiglio Nazionale delle Ricerche Ecole Polytechnique Federale de LausanneVia G. Moruzzi 1, 56126 Pisa, Italy CH-1015 Lausanne, SwitzerlandE-mail: firstname.lastname@example.org E-mail: email@example.com
Marco Conti received the Laurea degree in computer science from the University of Pisa, Italy, in 1987. In 1987 he joined theNetworks and Distributed Systems Department of CNUCE, an institute of the Italian National Research Council (CNR) where iscurrently a senior researcher. He has written over 90 research papers in the areas of design, modeling and performance evaluationof computer-network architectures and protocols. His current research interests include Internet architecture and protocols, wirelessnetworks, mobile computing, multimedia systems, and QoS in packet switching networks. He is co-author of the book MetropolitanArea Networks (Springer, London 1997). He was the coordinator of two minitracks (Mobile Ad-Hoc Networking and QoS inWeb Services) at the HICSS-34 conference. He is the Technical Program Chair of the second IFIP-TC6 Networking ConferenceNetworking2002. He is serving as a Co-Guest Editor for IEEE Transactions on Computers (Special issue on Quality of ServiceIssues in Internet Web Services) and ACM/Kluwer Mobile Networks & Applications Journal (MONET) (Special issue on MobileAd-Hoc Networks). He is a member of the IEEE and IFIP WG 6.3 and WG 6.8.
Silvia Giordano received her Ph.D. beginning of 1999 from the Institute of Communications and Applications (ICA) at EPFL,Lausanne. She is currently working as senior/first assistant at the ICA institute. Since 1999 she is editor of IEEE CommunicationMagazine of IEEE Communication Society. She is currently Guest Co-Editor of a Special Issue on Mobile Ad-Hoc Networks thatwill appear on MONET. Her current research interests include traffic control and mobile ad hoc WANs. She is a member of IEEE andIFIP WG 6.8.