Mobile Peer to Peer Computing for Next Generation Distributed Environments Advancing Conceptual and Algorithmic Applications pdf pdf

  Mobile Peer-to-Peer Computing for Next

Generation Distributed

Environments: Advancing Conceptual and Algorithmic Applications Boon-Chong Seet Auckland University of Technology, New Zealand

  I N FORM AT I ON SCI EN CE REFEREN CE Hershey • New York Director of Editorial Content: Kristin Klinger Senior Managing Editor: Jamie Snavely Managing Editor: Jeff Ash Assistant Managing Editor: Carole Coulson Typesetter: Chris Hrobak Cover Design: Lisa Tosheff Printed at: Yurchak Printing Inc. Published in the United States of America by Information Science Reference (an imprint of IGI Global)

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Mobile peer-to-peer computing for next generation distributed environments: advancing conceptual and algorithmic applications / Boon-Chong

Seet, editor. p. cm. Includes bibliographical references and index.

Summary: "This book is dedicated to the coverage of research issues, findings, and approaches to Mobile P2P computing from both conceptual

and algorithmic perspectives"--Provided by publisher.

  

ISBN 978-1-60566-715-7 (hbk.) -- ISBN 978-1-60566-716-4 (ebook) 1. Peer-to-peer architecture (Computer networks) 2. Mobile

communication systems. I. Seet, Boon-Chong, 1973- TK5105.525.M63 2009 004.6'52--dc22 2009001030 British Cataloguing in Publication Data A Cataloguing in Publication record for this book is available from the British Library.

All work contributed to this book is new, previously-unpublished material. The views expressed in this book are those of the authors, but not

necessarily of the publisher.

Editorial Advisory Board

  Ouri Wolfson, University of Illinois at Chicago, USA Takahiro Hara, Osaka University, Japan Jiannong Cao, Hong Kong Polytechnic University, Hong Kong Hsiao-Hwa Chen, National Sun Yat-Sen University, Taiwan Aaron Harwood, University of Melbourne, Australia John F. Buford, Avaya Labs Research, USA

List of Reviewers

  Chintada Suresh, Motorola Research Labs, Bangalore, India Thadpong Pongthawornkamol, University of Illinois at Urbana-Champaign, USA Kurt Tutschku, University of Vienna, Austria Thomas Repantis, Akamai Technologies, USA James Walkerdine, Lancaster University, UK Wei Wu, National University of Singapore, Singapore Spyridon Tompros, University of the Aegean, Greece Dawoud Dawoud, University of KwaZulu-Natal, South Africa Norihiro Ishikawa, Service and Solution Development Department, NTT Docomo Inc, Japan Alf Inge Wang, Norwegian University of Science and Technology, Norway Erkki Harjula, University of Oulu, Finland Jie Feng, University of Nebraska-Lincoln, USA Raphael Kummer, Distributed Computing Group, Université de Neuchâtel, Switzerland Tobias Hossfeld, University of Würzburg, Germany Fotis Loukos, Aristotle University of Thessaloniki, Greece Antonio Tadeu Azevedo Gomes,

  National Laboratory for Scientific Computing (LNCC), Brazil

  Leonardo B. Oliveira,

State University of Campinas (UNICAMP), Brazil

  Franca Delmastro, Institute for Informatics and Telematics, National Research Council, Italy Li Li, Communications Research Centre, Canada Thomas Kunz, Carleton University, Canada

  

Foreword ............................................................................................................................................. xvi

Preface ...............................................................................................................................................xviii

Acknowledgment .............................................................................................................................. xxiv

Section I

  

Information Retrieval and Dissemination

  Chapter I P2P Information Lookup, Collection, and Distribution in Mobile Ad-Hoc Networks ........................... 1 Raphaël Kummer, University of Neuchâtel, Switzerland Peter Kropf, University of Neuchâtel, Switzerland Pascal Felber, University of Neuchâtel, Switzerland Chapter II Data Dissemination and Query Routing in Mobile Peer-to-Peer Networks ......................................... 26 Thomas Repantis, University of California, Riverside, USA Vana Kalogeraki, University of California, Riverside, USA

Section II

Overlay and Mobility Management

Chapter III Overlay Construction in Mobile Peer-to-Peer Networks ...................................................................... 51 Jie Feng, University of Nebraska-Lincoln, USA Lisong Xu, University of Nebraska-Lincoln, USA Byrav Ramamurthy, University of Nebraska-Lincoln, USA Table of Contents

  Chapter IV Mobility Support in a P2P System for Publish/Subscribe Applications ............................................... 68 Thomas Kunz, System and Computer Engineering, Carleton University, Canada

Abdulbaset Gaddah, System and Computer Engineering, Carleton University, Canada

Li Li, Communications Research Centre, Canada Chapter V P2P over MANETs: Application and Network Layers’ Routing Assessment ....................................... 94 Leonardo B. Oliveira, University of Campinas (UNICAMP), Brazil Isabela G. Siqueira, Federal University of Minas Gerais (UFMG), Brazil Daniel F. Macedo, Université Pierre et Marie Curie-Paris VI, France José M. Nogueira, Federal University of Minas Gerais (UFMG), Brazil Antonio A. F. Loureiro, Federal University of Minas Gerais (UFMG), Brazil

Section III

Cooperative Mechanisms

Chapter VI Enabling Cooperation in MANET-Based Peer-to-Peer Systems ........................................................ 118 Fotis Loukos, Aristotle University of Thessaloniki, Greece Helen Karatza, Aristotle University of Thessaloniki, Greece Chapter VII Cooperation Strategies for P2P Content Distribution in Cellular Mobile Networks: Considering Selfishness and Heterogeneity ........................................................................................ 132 Tobias Hoßfeld, University of Würzburg, Germany Daniel Schlosser, University of Würzburg, Germany Kurt Tutschku, University of Vienna, Austria Phuoc Tran-Gia, University of Würzburg, Germany Chapter VIII Cooperation Strategies for P2P Content Distribution in Cellular Mobile Networks: Considering Mobility and Heterogeneity ............................................................................................ 152 Tobias Hoßfeld, University of Würzburg, Germany Michael Duelli, University of Würzburg, Germany Dirk Staehle, University of Würzburg, Germany Phuoc Tran-Gia, University of Würzburg, Germany Chapter IX Peer-Based Collaborative Caching and Prefetching in Mobile Broadcast ......................................... 166 Wei Wu, Singapore-MIT Alliance, and School of Computing, National University of Singapore, Singapore Kian-Lee Tan, Singapore-MIT Alliance, and School of Computing, National University of Singapore, Singapore

  

Section IV

Resource Management

  Chapter X Wireless Peer-to-Peer Media Streaming: Incentives and Resource Management Issues ................... 190 Mark Kai-Ho Yeung, The University of Hong Kong, Hong Kong Yu-Kwong Kwok, Colorado State University, USA Chapter XI Incentives for Resource Sharing in Ad Hoc Networks: Going Beyond Rationality ........................... 218 Panayotis Antoniadis, Université Pierre et Marie Curie, Paris 6, France

Section V

Security

Chapter XII Key Management for Dynamic Peer Groups in Mobile Ad Hoc Networks ....................................... 241 Johann van der Merwe, University of KwaZulu-Natal, South Africa Dawoud Dawoud, University of KwaZulu-Natal, South Africa Chapter XIII A Tool Supported Methodology for Developing Secure Mobile P2P Systems .................................. 283 James Walkerdine, Lancaster University, UK Peter Phillips, Lancaster University, UK Simon Lock, Lancaster University, UK

Section VI

Standards and Protocols

Chapter XIV Integration and Interworking of Fixed and Mobile P2P Systems ....................................................... 302 Spyridon L. Tompros, University of the Aegean, Greece Chapter XV Peer-to-Peer SIP for Mobile Computing: Challenges and Solutions .................................................. 326 Erkki Harjula, MediaTeam Oulu Group, University of Oulu, Finland Jani Hautakorpi, Ericsson Research Nomadiclab, Jorvas, Finland Nicklas Beijar, Department of Communications and Networking, TKK, Helsinki University of Technology, Espoo, Finland Mika Ylianttila, MediaTeam Oulu Group, University of Oulu, Finland

  

Section VII

Architectures and Platforms

  Chapter XVI Mobile P2P in Cellular Mobile Networks: Architecture and Performance ........................................ 349 Kurt Tutschku, University of Vienna, Austria Andreas Berl, University of Passau, Germany Tobias Hossfeld, University of Würzburg, Germany Hermann de Meer, University of Passau, Germany Chapter XVII Peer-to-Peer Networking Platform and Its Applications for Mobile Phones ...................................... 374 Norihiro Ishikawa, NTT DOCOMO, Japan Hiromitsu Sumino, NTT DOCOMO, Japan Takeshi Kato, NTT DOCOMO, Japan Johan Hjelm, Ericsson Research, Japan Shingo Murakami, Ericsson Research, Japan Kazuhiro Kitagawa, Keio University, Japan Nobuo Saito, Komazawa University, Japan Chapter XVIII Evaluation Platform for Large Scale P2P Mobile Ad-hoc Networks ................................................. 397 Raphaël Kummer, University of Neuchâtel, Switzerland Peter Kropf, University of Neuchâtel, Switzerland Jean-Frédéric Wagen, TIC Institute, University of Applied Sciences of Fribourg, Switzerland

Timothée Maret, TIC Institute, University of Applied Sciences of Fribourg, Switzerland

Section VIII

Applications and Services

Chapter XIX Mobile Peer-to-Peer Collaborative Framework and Applications ...................................................... 415 Alf Inge Wang, Norwegian University of Science and Technology, Norway Chapter XX Service Discovery Approaches to Mobile Peer-to-Peer Computing ................................................... 437

Antônio Tadeu A. Gomes, National Laboratory for Scientific Computing (LNCC), Brazil

Artur Ziviani, National Laboratory for Scientific Computing (LNCC), Brazil Luciana S. Lima, National Laboratory for Scientific Computing (LNCC), Brazil Markus Endler, Pontifical Catholic University of Rio de Janeiro (PUC-Rio), Brazil

  Chapter XXI Context-Aware P2P Over Opportunistic Networks ............................................................................ 460 Marco Conti, IIT Institute – CNR, Pisa, Italy Franca Delmastro, IIT Institute – CNR, Pisa, Italy Andrea Passarella, IIT Institute – CNR, Pisa, Italy

Compilation of References ............................................................................................................... 481

About the Contributors .................................................................................................................... 518

Index ................................................................................................................................................... 530

  Detailed Table of Contents

Foreword ............................................................................................................................................. xvi

Preface ..............................................................................................................................................xviii

Acknowledgment .............................................................................................................................. xxiv

Section I

  

Information Retrieval and Dissemination

This section includes two chapters that look at the issue of information retrieval and dissemination, each

exploring a different approach to addressing the issue.

  Chapter I P2P Information Lookup, Collection, and Distribution in Mobile Ad-Hoc Networks ........................... 1 Raphaël Kummer, University of Neuchâtel, Switzerland Peter Kropf, University of Neuchâtel, Switzerland Pascal Felber, University of Neuchâtel, Switzerland This chapter presents an enhanced Distributed Hash Table (DHT) to facilitate information retrieval (or

  lookup), and a new multicast tree construction algorithm built on top of the proposed DHT to con- struct a multicast tree distribution infrastructure for efficient information dissemination in mobile ad hoc networks.

  Chapter II Data Dissemination and Query Routing in Mobile Peer-to-Peer Networks ......................................... 26 Thomas Repantis, University of California, Riverside, USA Vana Kalogeraki, University of California, Riverside, USA This chapter proposes to adaptively disseminate special information called content synopses and

  presents a content-driven routing protocol that utilizes this information to efficiently guide the queries for actual content or information retrieval.

  

Section II

Overlay and Mobility Management

This section includes three chapters covering overlay construction, mobility support in overlay networks

in the context of publish/subscribe systems, and performance study of P2P overlay and MANET routing

protocols.

  Chapter III Overlay Construction in Mobile Peer-to-Peer Networks ...................................................................... 51 Jie Feng, University of Nebraska-Lincoln, USA Lisong Xu, University of Nebraska-Lincoln, USA Byrav Ramamurthy, University of Nebraska-Lincoln, USA This chapter reviews P2P overlay construction techniques for mobile networks, including tree- and mesh-

  based mobile P2P streaming networks. The authors also discuss advanced design issues, such as session mobility, robustness to high churn, incentive mechanism and content integrity, with relation to managing mobility in P2P overlays.

  Chapter IV Mobility Support in a P2P System for Publish/Subscribe Applications ............................................... 68 Thomas Kunz, System and Computer Engineering, Carleton University, Canada

Abdulbaset Gaddah, System and Computer Engineering, Carleton University, Canada

Li Li, Communications Research Centre, Canada This chapter examines the issue of subscriber mobility in publish/subscribe systems and presents a

  new mobility support solution through proactive context distribution, which is shown to perform better in terms of message loss/duplication, processing overhead and handoff latency than the conventional reactive approach.

  Chapter V P2P over MANETs: Application and Network Layers’ Routing Assessment ....................................... 94 Leonardo B. Oliveira, University of Campinas (UNICAMP), Brazil Isabela G. Siqueira, Federal University of Minas Gerais (UFMG), Brazil Daniel F. Macedo, Université Pierre et Marie Curie-Paris VI, France José M. Nogueira, Federal University of Minas Gerais (UFMG), Brazil Antonio A. F. Loureiro, Federal University of Minas Gerais (UFMG), Brazil This chapter investigates the performance of three MANET routing protocols: AODV, DSR, and DSDV

  under a Gnutella P2P network, and two P2P overlay protocols: Gnutella and Chord, over MANET with AODV as the underlying routing protocol through extensive computer simulations.

  

Section III

Cooperative Mechanisms

This section includes four chapters devoted to discussing the different mechanisms and applications

of peer-to-peer cooperation in mobile networks.

  Chapter VI Enabling Cooperation in MANET-Based Peer-to-Peer Systems ........................................................ 118 Fotis Loukos, Aristotle University of Thessaloniki, Greece Helen Karatza, Aristotle University of Thessaloniki, Greece This chapter outlines the current methods for cooperation in standard and MANET-based P2P networks. The

  authors also describe a number of use cases to illustrate the potential of peer-to-peer cooperation technology for mobile networks, including for such applications as knowledge sharing and social networking.

  Chapter VII Cooperation Strategies for P2P Content Distribution in Cellular Mobile Networks: Considering Selfishness and Heterogeneity ........................................................................................ 132 Tobias Hoßfeld, University of Würzburg, Germany Daniel Schlosser, University of Würzburg, Germany Kurt Tutschku, University of Vienna, Austria Phuoc Tran-Gia, University of Würzburg, Germany This chapter identifies selfish peers as a factor that degrades performance of P2P content distribution

  systems in cellular mobile networks and studies several cooperation strategies, including a new strategy CyPriM proposed by the authors to improve performance in the presence of selfish peers and heteroge- neous peer resources.

  Chapter VIII Cooperation Strategies for P2P Content Distribution in Cellular Mobile Networks: Considering Mobility and Heterogeneity ............................................................................................ 152 Tobias Hoßfeld, University of Würzburg, Germany Michael Duelli, University of Würzburg, Germany Dirk Staehle, University of Würzburg, Germany Phuoc Tran-Gia, University of Würzburg, Germany This chapter extends the discussion in the preceding chapter to consider the impact of mobility and

  vertical handover in a B3G network. The authors evaluate solutions such as mobile IP in the context of P2P content distribution, and present new strategies to manage mobility and improve utilization of scarce resources in such heterogeneous networks.

  Chapter IX Peer-Based Collaborative Caching and Prefetching in Mobile Broadcast ......................................... 166 Wei Wu, Singapore-MIT Alliance, and School of Computing, National University of Singapore, Singapore Kian-Lee Tan, Singapore-MIT Alliance, and School of Computing, National University of Singapore, Singapore This chapter reviews the problem of cooperative cache management in mobile environments that support data broadcast, and presents two peer-to-peer based schemes: CPIX and ACP for caching and pre-fetching information, respectively, to improve the data availability and access latency in mobile environments.

  

Section IV

Resource Management

This section includes two chapters on methods to foster resource sharing among peers: one in the

context of P2P media streaming in hybrid wireless networks; the other on general resource sharing in ad-

hoc networks.

  Chapter X Wireless Peer-to-Peer Media Streaming: Incentives and Resource Management Issues ................... 190 Mark Kai-Ho Yeung, The University of Hong Kong, Hong Kong Yu-Kwong Kwok, Colorado State University, USA This chapter focuses on energy cost sharing in wireless P2P media streaming, and presents two energy

  efficient protocols based on game-theoretic concepts to improve collaboration and streaming performance of peers in hybrid wireless networks.

  Chapter XI Incentives for Resource Sharing in Ad Hoc Networks: Going Beyond Rationality ........................... 218 Panayotis Antoniadis, Université Pierre et Marie Curie, Paris 6, France This chapter presents the case for social incentives to be used to foster resource sharing in ad hoc net-

  works, and proposes a new cross-layer concept that considers both social and economic solutions in application layer and network layer, respectively, in the design of incentive mechanisms.

  

Section V

Security

This section includes two chapters that concern security: one relates to the design of group key

management schemes for mobile ad hoc networks; the other looks at the development of secure

mobile P2P applications.

  Chapter XII Key Management for Dynamic Peer Groups in Mobile Ad Hoc Networks ....................................... 241 Johann van der Merwe, University of KwaZulu-Natal, South Africa Dawoud Dawoud, University of KwaZulu-Natal, South Africa

  This chapter provides a comprehensive coverage of conventional group key management schemes for dynamic peer groups, and discusses their design challenges and potential for MANET through an analysis of their communication and computation costs.

  Chapter XIII A Tool Supported Methodology for Developing Secure Mobile P2P Systems .................................. 283 James Walkerdine, Lancaster University, UK Peter Phillips, Lancaster University, UK Simon Lock, Lancaster University, UK This chapter presents a development tool that considers the user’s security, mobility, and P2P technology

  requirements, and proposes a suitable system architecture and sub-system designs for developing secure mobile P2P applications.

  

Section VI

Standards and Protocols

This section includes two chapters that cover current standards and protocols of interest to the research

and development of mobile P2P systems.

  Chapter XIV Integration and Interworking of Fixed and Mobile P2P Systems ....................................................... 302 Spyridon L. Tompros, University of the Aegean, Greece This chapter discusses the relevance of ITU standard architecture for next generation networks, and

  presents an overlay architecture for integrating P2P systems in interoperable fixed-mobile environments based on the IP Multimedia Sub-system (IMS) technology.

  Chapter XV Peer-to-Peer SIP for Mobile Computing: Challenges and Solutions .................................................. 326 Erkki Harjula, MediaTeam Oulu Group, University of Oulu, Finland Jani Hautakorpi, Ericsson Research Nomadiclab, Jorvas, Finland Nicklas Beijar, Department of Communications and Networking, TKK, Helsinki University of Technology, Espoo, Finland Mika Ylianttila, MediaTeam Oulu Group, University of Oulu, Finland This chapter reviews the current IETF standard for P2P-SIP (Session Initiation Protocol), which is de-

  signed to serve as a lightweight P2P based protocol for communication, session management, and service provisioning in infrastructured mobile networks such as wireless LAN and 3G cellular networks.

  

Section VII

Architectures and Platforms

This section includes three chapters on new architectures and platforms, including a new content-

distribution architecture for cellular networks, a P2P networking platform for mobile phones, and a platform

for emulation of P2P algorithms for MANET.

  Chapter XVI Mobile P2P in Cellular Mobile Networks: Architecture and Performance ........................................ 349 Kurt Tutschku, University of Vienna, Austria Andreas Berl, University of Passau, Germany Tobias Hossfeld, University of Würzburg, Germany Hermann de Meer, University of Passau, Germany This chapter first discusses the current incompatibilities between cellular mobile and P2P networks,

  and then presents a new P2P architecture for cellular mobile networks using content-distribution as an example application. The authors also investigate extensively the proposed architecture using analytical and simulation-based evaluation.

  Chapter XVII Peer-to-Peer Networking Platform and Its Applications for Mobile Phones ...................................... 374 Norihiro Ishikawa, NTT DOCOMO, Japan Hiromitsu Sumino, NTT DOCOMO, Japan Takeshi Kato, NTT DOCOMO, Japan Johan Hjelm, Ericsson Research, Japan Shingo Murakami, Ericsson Research, Japan Kazuhiro Kitagawa, Keio University, Japan Nobuo Saito, Komazawa University, Japan This chapter describes the architecture and protocols of a new P2P networking platform for mobile

  phones, and discusses the experimentation of the platform using three classes of mobile phone ap- plications namely, multimedia content search, instant messaging over Bluetooth, and remote access to networked home appliances.

  Chapter XVIII Evaluation Platform for Large Scale P2P Mobile Ad-hoc Networks ................................................. 397 Raphaël Kummer, University of Neuchâtel, Switzerland Peter Kropf, University of Neuchâtel, Switzerland Jean-Frédéric Wagen, TIC Institute, University of Applied Sciences of Fribourg, Switzerland

Timothée Maret, TIC Institute, University of Applied Sciences of Fribourg, Switzerland

This chapter presents Freemote, a Java-based emulation platform that could integrate emulated and real

  nodes such as the Berkeley motes to enable large-scale emulation of P2P algorithms for MANET with a high level of realism.

  

Section VIII

Applications and Services

This section includes three chapters that look at the development of collaborative applications, service

discovery, and context-awareness in mobile P2P services.

  Chapter XIX Mobile Peer-to-Peer Collaborative Framework and Applications ...................................................... 415 Alf Inge Wang, Norwegian University of Science and Technology, Norway This chapter describes the Peer2Me software framework for developing P2P applications that support

  collaboration on mobile phones with JavaME and Bluetooth. The authors also illustrate the potential use of the framework through a portfolio of developed applications that demonstrate a wide spectrum of collaborative functions.

  Chapter XX Service Discovery Approaches to Mobile Peer-to-Peer Computing ................................................... 437

Antônio Tadeu A. Gomes, National Laboratory for Scientific Computing (LNCC), Brazil

Artur Ziviani, National Laboratory for Scientific Computing (LNCC), Brazil Luciana S. Lima, National Laboratory for Scientific Computing (LNCC), Brazil Markus Endler, Pontifical Catholic University of Rio de Janeiro (PUC-Rio), Brazil This chapter presents a comprehensive coverage and comparative analysis of the current service dis-

  covery approaches in P2P systems for a variety of mobile networks, including infrastructured wireless networks, single-hop and multi-hop ad hoc networks.

  Chapter XXI Context-Aware P2P Over Opportunistic Networks ............................................................................ 460 Marco Conti, IIT Institute – CNR, Pisa, Italy Franca Delmastro, IIT Institute – CNR, Pisa, Italy Andrea Passarella, IIT Institute – CNR, Pisa, Italy This chapter discusses the use of context to enhance distributed services in opportunistic networks, and

  describes two context management architectures and their use in a context-aware opportunistic file sharing application that considers not only the social context of user, but also the utility of data objects for the context the user is in.

  

Compilation of References ............................................................................................................... 481

About the Contributors .................................................................................................................... 518

Index ................................................................................................................................................... 530

  xvi Foreword

  We are witnessing an explosive growth in the number of mobile computing devices, including smart phones, personal assistant devices, and sensors, and in wireless communication technologies and capa- bilities. Despite such growth, systems in which the devices collaborate directly to process information, namely mobile P2P systems, are in their infancy.

  This does not mean that research on the subject has not been done, but that the problem is very difficult. An example of an MP2P application that has been worked on for more than twenty years is routing, which is important in the digital battlefield, vehicular networks, and others. The problem is to route messages between a sender and a receiver that are out of each other’s transmission range, using the mobile devices as intermediaries. Despite the extensive amount of work on this problem, it is not solved yet.

  Furthermore, not all reasons for the slow start on mobile P2P systems are technological. For example, data broadcasting is a well understood mechanism that is technologically easy to implement and can facilitate mobile P2P systems development and deployment. Some of the chapters in this book discuss broadcasting. Yet it is not implemented by existing cellular service providers.

  Nevertheless, technology is a major stumbling block. The technological challenges include resource constraints on the mobile device, security and privacy, variable and/or disconnected network topology, and heterogeneity of devices. More specifically, it is hard to build systems when energy, memory, CPU power, and bandwidth resources are constrained on each one of the devices participating in the P2P system.

  Furthermore, the wireless medium is easier to tap into, and the devices are harder to protect physically. Thus, serious security and privacy concerns arise. Additionally, many mobile P2P systems cannot rely on an infrastructure for wireless communication among the devices. For example, an infrastructure of- ten does not exist in a battlefield. Thus, such systems depend on direct collaboration among the mobile devices via short-range wireless networks, which is difficult when mobility and failures continuously change the set of neighbors with which a node can directly communicate.

  This book addresses the technological challenges. It describes the problems, some existing solutions, and proposes new ones. The first section deals with the problem of finding information in a network lacking an infrastructure. Observe that this is different than the routing problem. It is harder in the sense that even the identity of the receiver, that is the location of information, is unknown; but easier in the sense that the information may be replicated and therefore routing to a single receiver is often not strictly necessary. The proposed solutions combine query and information dissemination in an intelligent way. P2P methods have been quite successful in the fixed world, and the second section explores adaptation of the successful methods (e.g. overlays) to the mobile world. Section III continues this exploration, with a distinction between mobile P2P systems that use an infrastructure, the ones that do not do so, and the ones that use a hybrid strategy. Section IV proposes that cooperation is a useful approach to xvii

  deal with the resource constraints, and it discusses incentives and mechanisms for cooperation. Section V discusses the critical topic of security, and sections VI, VII, and VIII discuss strategies that facilitate the development of mobile P2P systems. These strategies include standards, software tools, platforms, programming paradigms, service provision and discovery, and protocols.

  Overall, the book is an invaluable resource for both researchers and practitioners. It addresses the most important issues in mobile P2P systems, it is well organized, very readable, comprehensive, and presented at the right level of depth. It strikes a good balance between presentation of novel ideas, and survey of the state of the art.

  Ouri Wolfson University of Illinois, USA

Ouri Wolfson’s main research interests are in database systems, distributed systems, and mobile/pervasive computing. He

received his PhD degree in Computer Science from Courant Institute of Mathematical Sciences, New York University. He is

currently the Richard and Loan Hill professor of Computer Science at the University of Illinois at Chicago, where he directs

the Mobile Information Systems Research Center. He is also an affiliate professor in the Department of Computer Science at

the University of Illinois at Urbana Champaign. Ouri Wolfson is the founder of Mobitrac, a high-tech startup company that

had about forty employees before being acquired. Most recently he founded Pirouette Software Inc., and currently serves as its

President. Before joining the University of Illinois he has been on the Computer Science faculty at the Technion and Columbia

University, and he has been a Member of Technical Staff at Bell Laboratories. Ouri Wolfson authored over 150 publications,

and holds six patents. He is a fellow of the Association of Computing Machinery, and serves on the editorial boards of the

  

IEEE Transactions on Mobile Computing and the Springer’s Wireless Networks Journal. He received the best paper award for

“Opportunistic Resource Exchange in Inter-vehicle Ad Hoc Networks,” at the 2004 Mobile Data Management Conference. xviii Preface Computing systems are playing an essential role as an indispensable nervous system of modern society.

  The ubiquitous use of computing systems for the operation of our society, such as in our banking, public transportation, and healthcare systems, and in our daily lives for meeting our personal learning, entertain- ment and productivity needs, has resulted in them being of fundamental importance to keeping our modern society alive and thriving. The subsequent trend of integrating computing systems with communication networks such as the Internet further extended the reach of computing systems beyond geographical boundaries, ushering in an era of networked computing systems.

  Computer-mediated communication for distant human-to-human interaction, that is computer tele- phony systems, has become a cost-effective alternative to traditional telephone networks (Yarberry, 2002). Distant human-to-machine interaction has also benefited from the advent of networked computing, such as by enabling remote access to computing resources such as shared printers and databases. More recently, machine-to-machine (M2M) interaction has been a subject of interest in networked computing where ma- chines leverage on their network (wired or wireless) connectivity to directly interact with each other and in some cases make their own decisions without human intervention (Lawton, 2004).

  Networked computing systems have traditionally been based on the client-server model (Goodyear et al., 1999). In this architecture, the network consists of a server, typically a high-performance com- puter, and a group of clients. The server is the only provider of resources or services in the network, while the clients only request for resources or the execution of services from the server. It is apparent that each addition of a new client to the network is a new load added to the server. As the number of clients grows, the server capacity must increase to avoid becoming a bottleneck in the system. It is also apparent that in this model, the server represents a single point of failure in the network, and thus can be a major cause of downtime and a vulnerable target for security attacks.

  In recent years, the development of networked computing has evolved from the centralized and hier- archical model of client-server computing to encompass a more decentralized and distributed model of peer-to-peer (P2P) computing (Subramanian & Goodman, 2005). Using the widely-accepted definition by Schollmeier (2001), P2P is a network where the participants share a part of their own resources, which can be hardware resources such as processing power, storage capacity, network link capacity, printers, and so forth, or software resources such as media content, (e.g., pictures, videos and music files, and other digital content) information stored on databases, necessary to provide the service or content offered by the network. These resources on independent peers are in turn accessible by other peers directly without going through intermediate central control entities (i.e. the servers). The participants of such a network are thus serving as resource (service and content) providers as well as resource (service and content) consumers. xix

  Due to its promising potential to resolve the above issues of scalability and fault-tolerance in client- server computing, this radical and contrasting approach to computing has gained significant attention from both industry and academic research communities, and is suited for applications that have a mass of users in complex open distributed environments such as the Internet. Today, P2P technologies have been widely embraced by Internet users, and are best exemplified by popular file sharing systems such as eMule or BitTorrent, and Voice-over-P2P (VoP2P) applications such as Skype. Other emerging applications based on P2P that are gaining popularity include live or on-demand media (TV and video) streaming ap- plications, for example, Joost, Zattoo, and PPLive (Krieger & Schwessinger, 2008; Mushtaq, & Ahmed, 2008; Akkanen, Karonen, & Porio, 2008), and large-scale distributed online storage systems such as Wuala (Caleido AG, 2008), which provides its users with free online storage service for private or shared data by exploiting the unused disk space of participating computers on the Internet.

  In a parallel development with Internet P2P computing from late 1990s, the landscape of telecom- munications also experienced profound changes with the rapid proliferation of a plethora of wireless technologies ranging from technologies for wide area networks (e.g., UMTS, HSDPA, HSPA+), metro- politan area networks (e.g., Mobile WiMAX [802.16e], Mobile-Fi [802.20]), local area networks (e.g., 802.11a/g/n/p/s), personal area networks (e.g., Bluetooth, ZigBee, WiMedia), to more recently regional area networks based on emerging cognitive radios (802.22). Today, wireless-enabled laptops and PDAs, and cellular handsets with Internet access have become widely available and increasingly affordable. It is also not uncommon to find multi-mode terminals where computing devices or handsets have multiple modes of wireless connectivity such as 3G UMTS, WiFi (802.11) and Bluetooth. These technological advances are believed to have fueled the uptake of a mobile lifestyle where the daily lives of people are increasingly empowered by and dependent on wireless technologies. For instance, the increasing need of people to stay connected to the Internet at anytime from anywhere for work or for play. This brings forth a prediction that a significant portion of future users of P2P systems will be mobile, which calls for a need to investigate the suitability of developed P2P technologies for mobile and wireless networks, such as mobile cellular networks, infrastructured wireless local area networks (WLAN), and the infrastructure- less mobile ad hoc networks (MANET).

  Early investigations along this direction (such as Klemm, Lindemann, & Waldhorst, 2004; Ding & Bhargava, 2004) for MANET, and (such as Eberspächer, Schollmeier, Zöls, Kunzmann, & Für, 2004) for a heterogeneous mobile and fixed environment, have shown that contemporary P2P technologies performed neither well nor efficiently as they were designed for a relatively stable and resource-rich environment where hosts are stationary, well-endowed (i.e., in terms of processing power, memory, and energy) and connected by high bandwidth links. Thus, research is needed to innovate new approaches to P2P computing in a mobile environment. Specifically, the design of the mobile P2P systems should address the new challenges of dynamic changes in connectivity and resource availability, the new con- straints in mobile devices as well as wireless capacity, and respond to these constraints and changes in an intelligent, timely, and adaptive manner. However, the research possibilities of Mobile P2P computing are not limited to extending conventional P2P systems to perform effectively and efficiently under mobile conditions, but include, for instance, turning the new constraints into strengths by finding new usages of unique characteristics of mobile P2P, or creating new patterns of collaboration and sharing that can potentially move mobile applications and services into a new dimension for next generation distributed environments.

  This book is dedicated to the coverage of research issues, findings, and approaches to mobile P2P computing from both conceptual and algorithmic perspectives. Authored by some of the most leading xx

  experts in the field, and guided by an Editorial Advisory Board of prominent international researchers, the overall aim of this book is to serve as a valuable resource that captures the present state of the field, and to inspire ideas for future challenges through presenting the latest insights and thoughts of expert researchers on major topics of this emerging discipline.

  The key contribution of this book is in providing a much needed body of knowledge on mobile P2P computing in a single reference source, which to the best of our knowledge, is still largely missing from currently available book titles. Through a careful selection of topics that address some of the most important and essential issues in the field, including topics of both theoretical (e.g., models, algorithms, architectures) and practical interests (e.g., tools, platforms, applications), this book seeks to fill the gap in available titles with its dedicated and comprehensive coverage on mobile P2P computing. Readers would also benefit from the scholarly value of the book through its balanced and quality coverage of theoretical ideas and practical research. This book therefore comes as a timely contribution to the growing and flourishing research community in mobile P2P computing.

  The book is intended to provide an up-to-date advanced reading of important topics for academic researchers, graduate students, and senior undergraduate students in computer science, electrical and electronic engineering, and telecommunications, to enhance their research or studies. It is also intended for industry professionals such as R&D engineers, application developers, and technology business managers who wish to keep abreast of the recent developments in the field, and who are interested or involved in the research, use, design, development, and deployment of mobile P2P technologies.

  This book is organized into eight sections comprising a total of 21 chapters. Each section addresses a specific topic area or relates to works of a specific nature. Under each section, the chapters are gener- ally self-contained, thus readers are not required to read in the order in which they are listed, but could focus directly on those chapters that interest them. The following is a summary of contents covered in each section, including a brief description of each chapter listed under the section.