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TEAMFLY Team-Fly ® Page i Understanding WAP Wireless Applications, Devices, and Services Page ii For a listing of recent titles in the Artech House Mobile Communications Library , turn to the back of this book. Page iii Understanding WAP Wireless Applications, Devices, and Services Marcel van der Heijden Marcus Taylor Editors Page iv Disclaimer: This netLibrary eBook does not incude the ancillary media that was packaged with the originally printed version of the book. Library of Congress Cataloging -in-Publication Data Understanding WAP: wireless applications, devices, and services / Marcel van der Heijden, Marcus Taylor, editors. p. cm. — (Artech House mobile communications library) Includes bibliographical references and index. ISBN 1-58053-093-1 (alk. paper) 1. Wireless communication systems. I. Heijden, Marcel van der. II. Taylor, Marcus. III. Artech House telecommunications library. TK5103.2.U53 2000 621.3845— dc21 00-030611 CIP British Library Cataloguing in Publication Data Understanding WAP: wireless applications, devices, and services. — (Artech House mobile communications library) 1. Wireless communication systems 2. Computer network protocols I. Heijden, Marcel van der II. Taylor, Marcus 621.3'845 ISBN 1-58053-093-1 Cover and text design by Darrell Judd © 2000 ARTECH HOUSE, INC. 685 Canton Street Norwood, MA 02062 All rights reserved. Printed and bound in the United States of America. No part of this book may be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying, recording, or by any information storage and retrieval system, without permission in writing from the publisher. All terms mentioned in this book that are known to be trademarks or service marks have been appropriately capitalized. Artech House cannot attest to the accuracy of this information. Use of a term in this book should not be regarded as affecting the validity of any trademark or service mark. International Standard Book Number: 1-58053-093-1 Library of Congress Catalog Card Number: 00-030611 10 9 8 7 6 5 4 3 2 Page v Contents Preface xiii 1 Introducing the Wireless Application Protocol 1 1.1 Introduction 1 1.2 How it all started 2 1.2.1 Why was this done together? 2 1.2.2 A worldwide solution 3 1.2.3 The WAP Forum Ltd. 3 1.2.4 The first commercial version of WAP 3 1.3 A brief description of what it is all about 4 1.3.1 Optimized for wireless communications 4 1.3.2 Deck of cards 4 1.3.3 The WAP stack 4 1.4 Applications using WAP 7 1.4.1 Information retrieval on the Internet 7 1.4.2 The serviceperson application 8 1.4.3 Notification applications 8 1.4.4 Mobile electronic commerce 8 1.4.5 Telephony applications 8 1.5 Benefits and market opportunities 9 1.5.1 Operator benefits 9 1.5.2 Content provider benefits 10 1.5.3 End user benefits 10 1.6 Challenges to the network operator 10 1.6.1 Creating a service package 11 Page vi 1.7 What is next? 12 1.7.1 Interoperability 12 1.7.2 Products, of course! 12 1.7.3 Liaisons with other organizations 12 1.8 Conclusions 13 2 The Wireless Application Environment for Creating WAP Services and Applications 15 2.1 Introduction 15 2.2 The wireless markup language 17 2.2.1 Decks of cards 19 2.2.2 User input 20 2.2.3 Task invocation 21 2.2.4 Events 22 2.2.5 Variables and context 23 2.2.6 Other features of WML 24 2.3 Wireless markup language script 25 2.3.1 WMLScript variables and datatypes 26 2.3.2 WMLScript functions 27 2.3.3 Differences between ECMAScript and WMLScript 27 2.3.4 WMLScript statements 27 2.3.5 Wireless markup language script standard libraries 29 2.4 Byte-encoded WML and compiled WMLScript 29 2.4.1 Encoding of WML 30 2.4.2 Compilation of WMLScript 30 2.5 Overview of the wireless telephony application interface 30 2.5.1 WTAI libraries 32 2.6 Migrating from WWW to WAP 33 2.6.1 WML and HTML 33 2.6.2 WMLScript and JavaScript 34 2.6.3 Using CGI and WAP gateways 34 2.7 Markup languages and XML 35 2.8 User agent capabilities and content negotiation 36 2.9 Miscellaneous elements of WAP of interest to developers 37 2.9.1 Push 37 2.9.2 Wireless session protocol and HTTP headers 37 2.9.3 Binary encoding of wireless session protocol headers 38 2.9.4 Cache control using wireless session protocol headers 38 Page vii 2.10 Available software tools 39 2.11 WML language reference 39 3 Designing Effective User Interfaces for WAP Services 45 3.1 Introduction 45 3.2 The user interface design process 48 3.2.1 Holistic process 48 3.2.2 Customer satisfaction 49 3.2.3 Designing for tasks 50 3.3 Design principles 52 3.3.1 Economy 52 3.3.2 Modularity 52 3.3.3 Personality 52 3.3.4 Synthesis 53 3.4 Input techniques 53 3.4.1 Avoid text entry 54 3.4.2 Defaults 55 3.4.3 Lists 55 3.5 Navigation models 56 3.5.1 Form-based navigation 56 3.5.2 Question-and-answer navigation 57 3.5.3 Put the user in control 58 3.6 Testing the user interface 59 3.6.1 Different devices 60 3.7 Future developments 61 3.7.1 First-class WAP services 61 3.7.2 Adaptive user interfaces 61 3.8 Conclusions 62 4 Wireless Telephony Application: Telephony in WAP 65 4.1 Introduction 65 4.2 WTA architecture overview 67 4.3 The WTA framework components 68 4.3.1 The WTA user agent 68 4.3.2 The WTA interface 70 4.3.3 The repository 71 Page viii 4.3.4 An event-handling mechanism 72 4.4 The WTA server 72 4.5 WTA services and WTA service providers 73 4.6 WTA security model and access control 73 4.7 WTAI— interfacing WAP with the mobile network 74 4.7.1 The WTA interface design 74 4.7.2 Public WTAI 76 4.7.3 Network-common WTAI 77 4.7.4 Network-specific WTAI 78 4.7.5 Calling WTAI functions 79 4.7.6 WTA events 79 4.8 Repository 80 4.8.1 A persistent storage for fast service access 80 4.8.2 Channels and resources 80 4.8.3 Channel loading and unloading 83 4.9 Event handling 84 4.9.1 Event bindings 84 4.9.2 Event-handling procedure 84 4.9.3 Event parameters 86 4.9.4 Example: temporary event binding 87 4.9.5 Example: global event binding 87 4.10 Building a WTA application 88 4.10.1 The incoming-call handler service 88 5 Integrating WAP Gateways in Wireless Networks 97 5.1 Overview 97 5.2 Positioning of WAP functionality in a mobile network 98 5.2.1 WAP gateway 98 5.2.2 WAP-enabled mobile devices 99 5.2.3 WAP origin server 99 5.2.4 Wireless telephony application server 100 5.2.5 Additional support offerings by WAP gateway manufacturers 100 5.3 Functional requirements of a WAP gateway 103 5.3.1 Standardized functionality specified by the WAP Forum 104 5.3.2 Functionality required in integrating the standardized WAP functionality to an actual mobile network implementation 106 5.3.3 Value-added services provided by manufacturers 109 5.4 WAP gateway future enhancements 113 Page ix 5.4.1 Push applications 114 5.4.2 Security 114 5.4.3 Provisioning server 114 5.4.4 New generation mobile networks 114 5.4.5 Interim proprietary solutions 115 5.5 The WAP gateway— product differentiation factors 115 6 Introduction to WAP Push Services 117 6.1 Introduction 117 6.2 Definition of WAP push 118 6.3 What do we have today? 118 6.3.1 Push on the Web 119 6.3.2 Push in the wireless domain 120 6.3.3 Can the solutions converge? 120 6.4 The WAP push framework 121 6.4.1 Gateways, proxies, and servers 121 6.4.2 Push initiators 123 6.4.3 Push access protocol 124 6.4.4 The push proxy gateway 126 6.4.5 Push OTA protocol 130 6.4.6 Mobile client behavior 131 6.4.7 Service indication 132 6.4.8 Service loading 134 6.5 Security aspects 135 6.5.1 Internet security 135 6.5.2 WAP security 135 6.5.3 End-to-end security 136 6.5.4 Transitive trust 136 6.6 Making it happen 137 6.6.1 Understanding customer value 138 6.6.2 Understanding the value chain 138 6.6.3 Making the money 139 6.6.4 Some examples of push services 140 7 Wireless Application Protocol Security 143 7.1 Introduction 143 7.1.1 Case 1 144 7.1.2 Case 2 144 [...]... Comments on WTLS and WAP security 7.5 Conclusions 8 14 4 14 5 14 6 14 8 14 8 15 1 15 1 15 2 15 4 15 4 15 6 15 6 15 7 15 9 16 2 16 4 WAP for Operators 16 5 16 5 16 8 17 0 AM FL Y 8 .1 Introduction and background 8.2 Operator needs 8.3 Customer requirements 8.4 Critical success factors for WAP service introduction 8.4 .1 Generic critical success factors 8.4.2 WAP- specific critical success factors 8.5 WAP services 8.6 WAP business... multichannel applications 10 .14 Building financial WAP applications 10 .15 Sample banking application 10 .16 Possible mobile financial services applications using WAP 10 .17 The role of other service delivery channels 10 .18 The personal mobile phone and customer relation management 10 .19 Next generation of WAP- based financial services and applications 10 .20 Conclusion 19 2 19 2 19 4 19 6 19 9 2 01 202 202 203 205 207... Conclusion 17 5 17 5 17 7 17 8 TE 18 2 9 Extending Integrated Unified Messaging Solutions Using WAP 9 .1 Introduction 9.2 Unified messaging concept 9.3 Unified messaging and the wireless application protocol 9.4 Architecture of wireless application protocol access to unified messaging system 9.5 Using the wireless application protocol to expand unified messaging services 9.5 .1 The WAP portal 18 5 18 7 18 7 18 8 18 9 19 0... 10 .7 .1 SMS messages on GSM phones 10 .7.2 USSD messages on GSM phones 10 .7.3 Applications on the SIM of the phone 10 .7.4 Microbrowser in smart phones and PDAs 10 .8 Resident applications on the mobile device 10 .9 Choice of mobile commerce platform 10 .10 Existing mobile financial services and applications 10 .11 Principles of building scaleable n-tier applications 10 .12 Building WAP applications 10 .13 Building... 9.7.2 Wireless application protocol messaging and additional services in corporate systems 10 Mobile Financial Services and Applications 10 .1 Introduction 10 .2 A new electronic channel is born 10 .3 Who are the users of this new channel? 10 .4 Previous constraints to mobile commerce 10 .5 Breakthrough technology 10 .6 Strengths and weaknesses of the mobile channel 10 .7 The current range of mobile devices 10 .7 .1. .. 203 205 207 207 207 208 209 210 210 212 212 213 214 214 216 216 216 220 223 226 229 232 233 235 235 236 Page xii Acronyms About the Authors Index 239 243 247 Page xiii Preface Over the last five years or so a revolution has taken place, and continues to do so, that is changing the way we communicate and interact with each other and our environment The advent of the Internet and the ubiquitous presence... some and an opportunity to others, depending on the approach taken Most of all, it will release an enormous potential of services and applications for the end users In many ways WAP will probably change the world as the Internet and mobile communications have done before Page xiv Understanding WAP: Wireless Applications, Devices, and Services is a comprehensive description of many aspects of WAP It... such as Mobitex and paging systems 1. 2.3 The WAP Forum Ltd In December 19 97, the four parties formed a company, WAP Forum Ltd., to control and manage the continued development of WAP The first draft of the WAP 1. 0 specifications was released in April 19 98, and consequently the door for new members to enter the WAP Forum was opened In June 19 98, one year after the first joint meeting, the WAP Forum had... was approximately 40 1. 2.4 The first commercial version of WAP In May 19 99, 11 months after the release of the WAP 1. 0 specifications (and after a large number of working meetings), the first commercial version of WAP (WAP 1. 1) was finalized The number of members has increased steadily, and the present figure (May 2000) is now more than 200 members By now, many implementations of WAP components are Page... (vCalendar) [2], and so on Thus, existing standards and technologies are leveraged and can be easily migrated into WAP applications and services 1. 3.3.5 A layered telecommunication stack 1. 3.3.6 The WAP gateway AM FL Y Includes transport, security (see Chapter 7), and session layers In order to reach the Internet world, the WAP- enabled phones must travel via a WAP gateway (G/W) The WAP G/W acts as an . 10 1. 5.3 End user benefits 10 1. 6 Challenges to the network operator 10 1. 6 .1 Creating a service package 11 Page vi 1. 7 What is next? 12 1. 7 .1 Interoperability 12 1. 7.2 Products, of course! 12 1. 7.3. 11 4 5.4.5 Interim proprietary solutions 11 5 5.5 The WAP gateway— product differentiation factors 11 5 6 Introduction to WAP Push Services 11 7 6 .1 Introduction 11 7 6.2 Definition of WAP push 11 8 6.3. Introduction 14 3 7 .1. 1 Case 1 144 7 .1. 2 Case 2 14 4 Page x 7 .1. 3 Case 3 14 4 7 .1. 4 Case 4 14 5 7.2 Overview of cryptography 14 6 7.2 .1 Symmetric-key cryptography 14 8 7.2.2 Public-key cryptography 14 8 7.2.3