Showing papers on "Mobile search published in 1998"

Mobile networking through Mobile IP

Abstract: Mobile IP is a proposed standard protocol that builds on the Internet Protocol by making mobility transparent to applications and higher level protocols like TCP. Mobile IP (RFC 2002) is a standard proposed by a working group within the Internet Engineering Task Force; it allows the mobile node to use two IP addresses: a fixed home address and a care-of address that changes at each new point of attachment. The article presents the Mobile IP standard in moderate technical detail and points the reader toward a wealth of further information. Is also describes how Mobile IP will change with IP version 6, the product of a major effort within the IETF to engineer an eventual replacement for the current version of IP. Although IPv6 will support mobility to a greater degree than IPv4, it will still need Mobile IP to make mobility transparent to applications and higher level protocols such as TCP. There is a great deal of interest in mobile computing and apparently in Mobile IP as a way to provide for it. A quick Web search for items related to Mobile IP returned over 60,000 hits-impressive even given the notorious lack of selectivity for such procedures. Mobile IP forms the basis either directly or indirectly of many current research efforts and products. The Cellular Digital Packet Data (CDPD), for example, has created a widely deployed communications infrastructure based on a previous draft specification of the protocol. In addition, most major router vendors have developed implementations for Mobile IP.

Power management techniques for mobile communication

Abstract: In mobile computing, power is a hmited r=ouce. Like other devices, communication devices need to be prop erly managed to conserve energy. In this paper, we prment the design and implementation of an innovative trartspori level protocol capable of significantly reducing the power usage of the communication device. The protocol achieves power savings by selectively choosing short periods of time to suspend communications and shut down the communication device. It manages the important task of queuing data for future dehvery during periods of communication suspension, and decides when to restart communication. We *O address the tradeoff between reducing power consumption and reducing delay for incoming data. We present resdts from experiments using our implementation of the protocol. Th=e experiments measure the energy consumption for three simrdated communication patterns and compare the effects of different suspension strategies. Our r-tits show up to an 83~0 savings in the energy consumed by the communication. This can translate to a 6-9% savings in the energy consumed by an entire high end laptop or a savings of up to 40% for current hand-held PCs. The resdting delay introduced is sm~ (0.4-3.1 seconds depending on the power management level).

Offline viewing of internet content with a mobile device

Abstract: A method and system for transferring offline browsing content information of a wide area network from a host computer to a mobile device includes connecting the mobile device to the host computer and obtaining characteristic information of the mobile device pertaining to at least one of hardware and software capabilities of the mobile device. The content information is transferred from the host computer to the mobile device as a function of the characteristic information.

Online churn reduction and loyalty system

Abstract: A method and system are disclosed for providing subscriber loyalty and retention techniques. These techniques are suitable for mobile devices with small screens and limited keypad communication. This system and method allows mobile subscribers who have been identified as being likely candidates for churning, to efficiently, visually and interactively, review an offer for a mobile service plan better meeting the subscriber's needs. The subscriber can review and execute the offer using the display and interface of a mobile device.

Cryptographic Traces for Mobile Agents

Abstract: Mobile code systems are technologies that allow applications to move their code, and possibly the corresponding state, among the nodes of a wide-area network. Code mobility is a flexible and powerful mechanism that can be exploited to build distributed applications in an Internet scale. At the same time, the ability to move code to and from remote hosts introduces serious security issues. These issues include authentication of the parties involved and protection of the hosts from malicious code. However, the most difficult task is to protect mobile code against attacks coming from hosts. This paper presents a mechanism based on execution tracing and cryptography that allows one to detect attacks against code, state, and execution flow of mobile software components.

A system for providing targeted internet information to mobile agents

Abstract: An Actively Broadcast URLs for Drive-By Internet Information (ABU-DaBII) system provides for the just-in-time distribution of information through mobile information terminals. The system involves the Internet as the primary source of the information and includes a mobile information terminal as the output device and a local agent which is locally operated. The mobile information terminal includes a receiver, a URL queue and a WWW renderer/browser. The local agent includes a short-range transmitter to distribute information pointers to the mobile information terminal and a mechanism for transferring data into the transmitter.

An active transcoding proxy to support mobile web access

Abstract: In this paper, we present a proxy based system (MOWSER) to support web browsing from mobile clients over wireless networks. Mowser is a proxy agent between the mobile host and the web server, which performs active transcoding of data on both upstream and downstream traffic to present web information to the mobile user according to the QoS parameters set by the user. Active transcoding is defined as modifying the HTTP stream in situ, and it is entirely transparent to the user. Further, our system does not pose any additional requirements on the mobile user. This is an improvement over other proxy based systems, which only transcode images on the downstream and are mostly not configurable. While developed for mobile users, such a system can actually be useful in any low bandwidth scenario.

The mobiware toolkit: programmable support for adaptive mobile networking

Abstract: Existing mobile systems (e.g., mobile IP, mobile ATM, and third-generation cellular systems) lack the intrinsic architectural flexibility to deal with the complexity of supporting adaptive mobile applications in wireless and mobile environments. We believe that there is a need to develop alternative network architectures from the existing ones to deal with the tremendous demands placed on underlying mobile signaling, adaptation management, and wireless transport systems in support of new mobile services (e.g., interactive multimedia and Web access). We present the design, implementation, and evaluation of mobiware, a mobile middleware toolkit that enables adaptive mobile services to dynamically exploit the intrinsic scalable properties of mobile multimedia applications in response to time-varying mobile network conditions. The mobiware toolkit is software-intensive and is built on CORBA and Java distributed object technology. Based on an open programmable paradigm developed by the COMET Group, mobiware runs on mobile devices, wireless access points, and mobile-capable switch/routers providing a set of open programmable interfaces and algorithms for adaptive mobile networking.

Mobile Objects and Mobile Agents: The Future of Distributed Computing?

Abstract: This paper will lead you into the world of mobile agents, an emerging technology that makes it very much easier to design, implement, and maintain distributed systems You will find that mobile agents reduce the network traffic, provide an effective means of overcoming network latency, and perhaps most importantly, through their ability to operate asynchronously and autonomously of the process that created them, helps you to construct more robust and fault-tolerant Read on and let us introduce you to software agents — the mobile as well as the stationary ones We will explain all the benefits of mobile agents and demonstrate the impact they have on the design of distributed systems before concluding this paper with a brief overview of some contemporary mobile agent systems

What is a file synchronizer

Abstract: Nloblle computing devices intended for disconnected operation, such as laptops and personal organizers, must employ optimistic replication strategi~ for user files. Unlike traditional distributed systems. such devices do not attempt to present a “single filesystem” semanti~ users are aware that their fles are replicated, and that updates to one rephca till not be seen in another until some point of synchronization is reached (often under the user’s exphcit control). A variety of tools, collectively called file synchronizers, support this mode of operation. Unfortunately, present-day synchronizers seldom give the user enough information to predict how they will behave under all circumstances. Simple slogans fike “Non-confecting updates are propagated to other replicas” ignore numerous subtletim—e.g., Precisely what constitutes a confict be @een updates in different replicas? What does the synchronizer do if updatw confict? What happens when fles are renamed? What if the directory structure is reorganized in one replica? Our god is to offer a simple, concrete, and precise frame work for describing the behavior of file synchronizers. To this end, n?edivide the synchronization task into two conceptually distinct phasm update detection and Reconciliation. We dEcuss each phase in detail and develop a straightforn’ard specification of each. We sketch our on prototype implementation of these specifications and discuss how they apply to some existing synchronization tools.

Visual interface to mobile subscriber account services

Abstract: The present invention discloses a method and apparatus for providing visual interfaces to mobile subscriber account services suitable for mobile devices with a small screen and phone keypad communicating, via a wireless data network, with a remotely located server device providing the mobile subscriber account services. Apart from the interactive voice system and other related systems providing access to subscriber account services, the present invention provides direct visual interface to the mobile subscriber account services and allows mobile subscribers to efficiently, visually and interactively, for example, access desired information and place service requests, through the limited screen and phone keypad at anytime from anywhere with limited costs to the service providers and maximum convenience to mobile subscribers.

Mobile agents - enabling technology for active intelligent network implementation

Abstract: The emerging notion of active networks describes the general vision of communication network evolution, where the network nodes become active because they take part in the computation of applications and provision of customized services. In this context mobile agent technology and programmable switches are considered as enabling technologies. This article looks at the impact of mobile agent technology on telecommunication service environments, influenced by the intelligent network (IN) architecture. The authors illustrate how the integration of mobile agent platforms into IN elements, notably into the IN switches, will realize an active IN environment. This enables telecom services implemented through mobile service agents on a per user basis to be instantly deployed at programmable switching nodes, which results in better performance and fault tolerance compared to traditional IN service implementations.

Flexible network support for mobility

Abstract: Fueled by the large number of powerful tight-weight portable computers, the expanding availability of wirel= networks, and the popularity of the Internet, there is an increasing de mand to connect portable computers to the Internet at any time and in any place. However, the dynamic nature of such connectivity requires more flexible network support than has typically been atiable for stationary workstations. ThM paper introducw the following two me~anisms, in the context of Mobile 1P [24], to ensure a mobile host’s convenient and efficient communication with other hosts in a &anging environment. One me&anism supports multiple packet defivery methods (such as regular 1P or Mobile 1P) and adaptively selects the most appropriate one to use Wcordlng to the char=teristim of eti trfic flow. The other medanism enables a mobile host to make use of multiple wtive network interfww simultaneously and to control the selection of the most dwirable network interfaces for both outgoing and incoming pdets for different traffic flows. We demonstrate the usefdnm of these two network layer me&anisms and describe how they are implemented.

Mobile Web access using eNetwork Web Express

Abstract: The mobile computing environment poses severe problems for Web browsing and Web-based applications. Mobile communication links are typically slow, expensive, and unreliable. This is especially true of wide-area wireless networks, which are becoming increasingly popular. Furthermore, both voluntary and involuntary disconnections from servers are common in the mobile environment, and the standard browsing model provides no support for disconnected operation. In addition, the usual request/response model of browsing is synchronous, which means that congestion in the network and Web servers cannot be masked from users. This article describes eNetwork Web Express, a software system that addresses these issues. Paired proxies are used to optimize communication in low-bandwidth networks and to enable a browsing model in which both disconnected and asynchronous operations are supported. The resulting environment allows Web-based applications to be used effectively in a mobile setting.

Digital library information appliances

Abstract: Although digital libraries are intended to support education and knowledge work, current digital library interfaces are narrowly focused on retrieval. Furthermore, they are designed for desktop computers with keyboards, mice, and high-speed network connections. Desktop computers fail to support many key aspects of knowledge work, including active reading, free form ink annotation, fluid movement among document activities, and physical mobility. This paper proposes portable computers specialized for knowledge work, or digital library information appliances, as a new platform for accessing digital libraries. We present a number of ways that knowledge work can be augmented and transformed by the use of such appliances. These insights are based on our implementation of two research prototype systems: XLibris, an “active reading machine,” and TeleWeb, a mobile World Wide Web browser.

Adtranz: a mobile computing system for maintenance and collaboration

Abstract: The paper describes the mobile information and communication aspects of a next generation train maintenance and diagnosis system, discusses the working prototype features, and research results. Wearable/Mobile computers combined with the wireless technology improve efficiency and accuracy of the maintenance work. This technology enables maintenance personnel at the site to communicate with a remote helpdesk/expertise center through digital data, audio, and image.

Applying Location-Aware Computing for Electronic Commerce: Mobile Guide

Abstract: Location-Aware applications for supporting the mobile user have proven significant relevance for future telecommunication and computing. Based on the state-of-the-art analysis and the business view, the paper evaluates the outcome of the labs and the requirements of commercial usage. A system architecture is proposed from the technical perspective. The required support of heterogeneous resources leads to the necessity of an adequate middleware platform. Merging data from different sources and constraints in the transmission and presentation capabilities of the mobile side require sophisticated media scaling and conversion capabilities. The envisaged service architecture leads finally to the discussion of the prototype developed on our Mobile Guide test-bed.

Mobility and security management in the GSM system and some proposed future improvements

Abstract: Important aspects of mobility and security in the Global System for Mobile communications (GSM) system are discussed in this paper. Mobility management functions are broadly categorized into three groups: a) mobile turned on, b) mobile turned off, and c) mobile in conversation. The paper first outlines the mobile synchronization sequence followed by its mobility functions: mobile identification, authentication, international mobile station identity attach/detach, and its location update. The important role of security in the GSM system is fully explored, including authentication, encryption, and positive identification of mobile equipment before the user is provided with the service. The future of mobility management with respect to subscriber identification module roaming, intersystem roaming, advancement in mobile service, and its impact on data base requirements, is covered.

Web Content Delivery to Heterogeneous Mobile Platforms

Abstract: It is widely acknowledged that information such as web content should be adapted for mobile platforms to account for restrictions in mobile environments. As emerging mobile platforms such as different kinds of Personal Digital Assistant (PDA) tend to vary largely in their capabilities, we suggest that adaptation should be platform-specific. Common approaches for content adaptation are automated conversion and explicit specification of adapted content, with a trade-off between quality and development/maintenance effort. As alternative avoiding this trade-off, we propose a simple object-oriented framework for content adaptation. To facilitate the use of this framework in the Web, we base our approach on the object-oriented WebComposition model and its XML-based implementation WCML. We apply our object-oriented approach to an example application to demonstrate how object-oriented specification of platform-adapted content reduces development/maintenance effort.

Cache management for mobile databases: design and evaluation

Abstract: Communication between mobile clients and database servers in a mobile computing environment is via wireless channels with low bandwidth and low reliability. A mobile client could cache its frequently accessed database items into its local storage in order to improve performance of database queries and availability of database items for query processing during disconnection. We describe a mobile caching mechanism for a mobile environment utilizing point to point communication paradigm. In particular, we investigate issues on caching granularity, coherence strategy, and replacement policy of mobile caching. Via a detailed simulation model, we compare our proposed caching mechanism with conventional ones and discover that our mobile caching mechanism outperforms conventional ones in most situations.

Supporting Collaboration in Mobile-Aware Groupware

Abstract: This paper builds on the experiences gained from the extensive work carried out during the MOST project [MOST,95]. This project investigated the use of mobile technologies to support multimedia collaboration between highly mobile field engineers in the safety critical domain of the U.K. power distribution industry. The MOST team developed a prototype distributed groupware application which was arguably the first collaborative mobile application ever built that was capable of adaption in a mobile environment [Cheverst,94]. The application was designed as an expandable toolkit comprising a number of modules including a shared GIS module. This module enabled groups of field engineers to perform spatially-aware collaboration by supporting the display and annotation of network schematics across groups. The MOST application was evaluated by real end-users in a trial scenario using the GSM service for communications. This evaluation provided a valuable set of implications regarding the development of distributed groupware in conjunction with mobile technologies.

Secure and mobile networking

Abstract: The IETF Mobile IP protocol is a significant step towards enabling nomadic Internet users. It allows a mobile node to maintain and use the same IP address even as it changes its point of attachment to the Internet. Mobility implies higher security risks than static operation. Portable devices may be stolen or their traffic may, at times, pass through links with questionable security characteristics. Most commercial organizations use some combination of source-filtering routers, sophisticated firewalls, and private address spaces to protect their network from unauthorized users. The basic Mobile IP protocol fails in the presence of these mechanisms even for authorized users. This paper describes enhancements that enable Mobile IP operation in such environments, i.e., they allow a mobile user, out on a public portion of the Internet, to maintain a secure virtual presence within his firewall-protected office network. This constitutes what we call a Mobile Virtual Private Network (MVPN).

Performance Evaluation of Forwarding Strategies for Location Management in Mobile Networks

Abstract: This paper presents a methodology for evaluating the performance of forwarding strategies for location management in a personal communication services (PCS) mobile network. A forwarding strategy in the PCS network can be implemented by two mechanisms: a forwarding operation which follows a chain of databases to locate a mobile user and a resetting operation which updates the databases in the chain so that the current location of a mobile user can be known directly without having to follow a chain of databases. In this paper, we consider the PCS network as a server whose function is to provide services to the mobile user for ‘updating the location of the user as the user moves across a database boundary’ and ‘locating the mobile user’. We use a Markov chain to describe the behavior of the mobile user and analyze the best time when forwarding and resetting should be performed in order to optimize the service rate of the PCS network. We demonstrate the applicability of our approach with hexagonal and mesh coverage models for the PCS network and provide a physical interpretation of the result.

NaviPoint: an input device for mobile information browsing

Abstract: A mobile computing environment imposes various restrictions on users. For example, most mobile devices have a liited screen size, and it may be di&ult to watch the screen closelyWhile the user is walking or standing in a bus or train, he or she may have only one hand free to manipulate the device. Therefore, some new operation method must be developed for comfortable information browsing in the mobile environment. In this paper, several existing methods are first introduced and compared from the viewpoint of their applicability in a mobile environment. A new input device for such an environment, named WaviPoint,” is then introduced NaviPoint is a specialized device for mobile information browsing. By using this device, a user cau perform three types of input “analog input,” “digital input.,” and “click input?’ with just one finger. After an explanation of the conceptual structure and a qualitative analysis of NaviPoint, the structure of a prototype is described Experiments using the prototype show that information browsing is possible with an overhead of less than 50% on the usual “mouse and scroll bar” method

Application-oriented network modeling with mobile agents

Abstract: The research thrust of the Perpetuum project is the use of mobile intelligent agents for network management. Mobile agents are migratory programs that move from one host to another to access remote data and services at their location, rather than transporting the data to a central location. The use of mobile agents affords new opportunities for the distribution of processing and control in network management due to their autonomous and cooperative nature. We envision a network manager as a suite of problem-specific applications that launch and/or communicate with autonomous mobile network agents that we call netlets. The intent is to provide an extensible set of tools that shift the operator's focus from MIB browsing to problem-solving. In this poster, we demonstrate this shift by applying mobile agents to network modeling. Instead of regarding the network model as the repository of the network topology, a network model is defined as an application-oriented view of the network. Depending on the application, the view will not only be defined in terms of a set of static components, but also in terms of the dynamic status of these components. The mobile agent implementation of a network model browser is explained, followed by an exploration of innovative extensions that transform this model discovery tool into a problem-browser.

Method and apparatus for communication using a mobile internet in a mobile communication network

Abstract: Mobile Internet system and method in a mobile communication network is disclosed, in which a mobile host given an Internet Protocol address uses an existing Code Division Multiple Access type mobile network and an Home Location Register and an Inter-Working Unit in a personal communication system network to establish communications without restricting a mobile host to a particular network. The mobile Internet system and method includes a plurality of mobile hosts, a plurality of mobile access points, a mobile router, and a plurality of gateway routers.

Integrating mobile agents into the mobile middleware

Abstract: Mobile agents are a new paradigm for distributed computing that is especially well suited for mobile computing over global wireless networks. This paper describes the approach taken in the ACTS On TheMove project to integrate a mobile agent system into the Mobile Application Support Environment (MASE), a middleware for mobile computing. In this project, an existing mobile agent system was adapted for the requirements of mobile computing. We present the changes that had to be made to the agent system to adapt it to the wireless communication. We also present some of the application areas where a mobile agent system is suitable for mobile communication. We describe an agent based pre-fetcher application where an agent operaes disconnected from the user on the fixed network and prepares web pages for the anticipated next connection of the user using the Quality-of-Service trading functions available in MASE.

Mobile agents for enabling mobile user aware applications

Abstract: Mobile agents based computing has been propounded as the possible approach to next generation computing. The approach has been shown to be e ective in di erent domains, especially in the area of mobile and partially connected computing. We describe the design and implementation details of MAGENTA (Mobile AGENT environment for distributed Applications) and the mechanisms it provides for enabling applications supporting mobile users. MAGENTA is a generic mobile agent environment and provides the agents the capabilities of autonomy, reactivity, proactivity and communication. In order to demonstrate the functionalities provided by MAGENTA to mobile users we have applied it in the domain of network management in order to implement a Mobile Network Manager (MNM). We also present the performance evaluation results of MAGENTA.