CORDIS Archive
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Dr. Björn Schiemann
Bjoern.Schiemann@mchp.siemens.de
Siemens AG, Munich, Germany
Ernö Kovacs
kovacs@fb.sony.de
Sony International (Europe) GmbH, Fellbach, Germany
Summary
Introduction and overview
The flexible working mobile user
Enabling technologies
Mobile agents and AMASE
New functionality for the flexible working user
Impact on IST
Conclusion and outlook
References
Today’s world economy requires flexibility in the work place from an ever increasing variety of users. The flexible-working user requires advanced networking services which allow him or her to stay connected to information sources and network services. Mobile communications networks support this demand by offering communications facilities at anytime, (nearly) anywhere and in many different forms. Nevertheless, connectivity cannot always be guaranteed. Further developments in technology areas like PDA, mobile networks and the Internet will open up a host of different communications means and alternatives. The Internet extends over currently used workstations, desktops and laptops, it will embrace mobile phones, consumer electronics and home appliances. In the following, we argue that mobile agents can complement existing communication means. We describe the results of the ACTS AMASE project that has adapted a mobile agent system for wireless communication networks. We describe the testbed application and give an outlook on future trends. Today’s Internet is tied to the workstation at work, the desktop PC at home or the Laptop during travelling. Currently we can see the introduction of small mobile devices on the market. Clearly, these devices are not targeted to perform everyday work such as word processing, programming or retrieval of large sets of data from a database. For these tasks mobile devices are too limited. They are more companions to the user allowing him or her to perform simple tasks, giving access to some personal information (address book, calendar), and offer small pieces of functionality which are useful in the everyday life.Mobile devices are becoming very powerful when they are combined with today's wireless or cellular networks. They change their role from a pure companion to a communicator allowing all kinds of information exchange, e.g. email access, file upload, service access, or information retrieval. Further innovative use of these devices might come when they offer easier user interfaces (e.g. speech input), when improved Web access is offered through special adaptation of contents and services, and when communication with other devices becomes pervasive.
However, the current (Web-)server centric approach seems to limit the range of services that can be used. Server centric network services can only be used when either (a) the user is online or (b) some service providers are offering dedicated pre-programmed services to the user. The disadvantages of this approach are obvious. The capabilities of the network can only be used when online or when a service provider offers a certain service. Furthermore, the user must be connected to the appropriate server, although Java applets (and other active contents) can load new functionalities directly into the mobile devices. However In the case of disconnection, the new functionality vanishes.
To overcome these shortcomings, researchers are investigating the mobile agent paradigm. Mobile agents are software units that can move between network nodes during runtime taking their state with them. This enables the possibility to launch customised and well-adapted application code within the network. The same piece of code may also migrate to mobile devices and thereby enhances the local functionality. While the power of mobile agents is obvious, it is also clear that this new technology introduces new issues which must be solved in order to attain widespread use of this technology.
A phenomenon of today’s world is the flexible working user. In this paper, we discuss the enabling technologies which allow the flexible working mobile user to access net-based services through the use of mobile agents. We also describe the results of the ACTS AMASE project (AC346), an ongoing project in the 4th European R&D framework. We emphasise the possibilities that the AMASE agent environment offers the flexible working user. In this discussion, we describe new functionalities for the mobile user and the customisation aspects of the AMASE system. From the lessons learned in the AMASE project, we derive requirements and new ideas for future research in the IST program. Finally, we summarise our work and give an outlook on future developments.
In this section, we ask what makes up the flexible working mobile user? Why does he or she need access to net-based services? And why are today’s networked communication systems such as e-mail and Web-access just not enough?The flexible working mobile user has many roles. He/she might be the hard working marketing specialist who must travel abroad to visit new customers. He/she needs information about the local culture, local habits and other localised information. It might be the supervising engineer leaving the office and driving to a construction site. He/she might require access to office information, want to receive travel information for other locations as well or in general be interested in information directly effecting current business. He/she might also be the worker at the assembly line who needs direct data access about the desired car configuration of the customer to build a cost-effective, custom made product.
All these examples show that in today’s highly technical work environment, information access, digital communication possibilities and personalised services are more and more coming to every workplace. We expect that the flexible user has access to a broad range of databases, information sources as well as electronically accessible services needed for everyday work. Given the amount of possibilities offered today by the Internet, the flexible working user is not satisfied by a pre-defined set of information and "fixed" service offerings which somebody has pre-configured (e.g. an IT department). He/she expects that this information is available at anytime, anywhere and in any form. Furthermore, the user wants dynamically responsive services from the network, personalised to their own needs and using context information about the current reachability and situation.
The user is already using many different digital communications devices (like mobile phones or PDAs) enabling access to services in different ways. It is a requirement for the mobile user to have the network actively search, filter, and present information. The user is willing to customise the offered services according to personal needs.
On the other hand he or she is also familiar with the risks and dangers of a networked world. Privacy and protection against information misuse is of great importance. Thus controlling the electronic marks and tracks left at Web-servers is an important issue.
In parallel to these developments computer devices became mobile. Laptops and notebooks with their integrated displays could easily be packed into luggage and used on business trips. Since these devices were still too big for many business applications the personal digital assistants (PDA) provided help. With a small display and a tiny keyboard but without a hard disk they provide office applications like simplified text and table processing, and they fit into a jacket pocket. The Psion 5mx Pro which is used in the AMASE project is a good example. Some palm-sized devices even got rid of the keyboard and rely on touch-screens with the recognition of handwriting instead. Examples are the Apple Newton or the 3com Palm Pilots.
Many manufacturers recognised that both the mobile phones and computers should become more integrated. Thus interconnects like modems and phone adapters became available which gave mobile computers access to net-based services including the internet, email and fax. Currently a convenient way for connecting mobile phones and computers is the infrared modem (IrDA), but other interconnect possibilities like the short range wireless network Bluetooth have emerged. Furthermore, the ongoing integration of mobile devices is driven by standardisation activities, for instance the Wireless Application Protocol (WAP) which is already supported by some cellular phones. In addition, services converters have become available which allow access to the Internet from PDAs but these devices have limited display and processing capabilities.
Future access networks will be based on GSM, GPRS, UTRA and WLAN/Hiperlan access. In particular, the evolution of cellular subscribers for GSM is quite significant and increasing very rapidly. Today there are approximately 350 GSM networks operational in more than 130 countries/ regions all over the world. Future networks will be based on the GSM core network enhanced with GPRS (General Packet Radio Service) packet data functionality. This evolution of GSM will work in conjunction with WCDMA (Wideband Code Division Multiple Access) radio access. At the end of 1999, GPRS is due to come into service. GPRS will support mobile connections to IP networks forming a seamless gateway for integration with the Internet. Applications could include Intra/Internet packet access at various data rates or IP conferencing including voice over IP networks.
3rd generation systems - the UMTS Terrestrial Radio Access (UTRA) - will enable tomorrow’s wireless Information Society, delivering high-value broadband information, electronic commerce and entertainment services to mobile users via fixed, wireless and satellite networks.
In the area of satellite systems the ‘Global Mobile Personal Communications by Satellite (GMPCS)’ technology is in use. It is intended to offer seamless global voice and data communication using sophisticated satellite systems in orbits ranging from 10.000 km - medium (MEO), geo-stationary (GEO, 36.000 km), to low earth orbit (LEO, 1.000 km). However, all these wireless networks possess substantial drawbacks e.g. GSM offers only limited bandwidth - typically 9600 bit/s. With respect to local area networks WLAN and DECT systems are in common use. Upcoming standards like HIPERLAN (High Performance Radio Local Area Network) standardised by ETSI are under development. Amongst other wireless technologies HIPERLAN will offer high data rates even without any infrastructure in the network. This will opens new applications to wireless data communications in local areas.
Thus, the foreseeable availability of new satellite systems and UMTS services will, in combination with existing technologies, create additional opportunities for new types of telecommunication services and applications, in particular support for new working methods for mobile users.
On the other hand, the services are rarely designed according to the needs of different mobile users with respect to:
The Internet and the IP technologies are more and more used as a universal platform for the integration of telecommunication services within public and corporate networks. In order to be able to meet the requirements of new working methods and applications next generation IP networks have to provide advanced functionality like support of quality of service or broadcast distribution capabilities. Mobility management functions like Mobile IP are considered for inclusion into the next set of standards although the security debate is far from over.
With the evolution of Web-based infrastructures, we observe two additional trends:
The AMASE system is an agent system based on Java. It is used to set up an agent environment for agent-based applications. In the following sections we briefly describe the concept of an agent environment, the system architecture of the AMASE system, and the way agent-based applications may be built.
Figure 25: The agent environment
The AMASE agent platform may be installed on server machines, desktops and mobile devices like notebooks or palmtops running Java or Personal Java. For instance, the AMASE system was successfully ported to the EPOC32 simulator for the PSION5 palmtop. While the base software is the same for servers and desktops, it is different for a mobile device like a PDA because of the device inherent resource constraints.
In addition to agent platforms, external services may be installed and integrated into an agent environment. By the use of these external services, agents may communicate with systems outside of the agent environment. The AMASE "Primary Telecommunication Services" agent package demonstrates how this can be used to give agents to access existing telecommunication services like SMS or Fax. Figure 25 shows an example of the AMASE agent environment.
The administrative part of the agent API provides for mobile agent initiation, monitoring their behaviour and freezing or stopping their execution. An agent platform does not only offer the agent API, but it may also provide additional services. For instance, these may be specialised agent services or access to external services. Each of these are encapsulated by a System Agent (SA). A SA is a privileged agent usually loaded at start-up of the agent system. It executes in the security context of the agent system owner. This means that unlike a mobile agent, SAs have access to system resources like the file system, communication lines, etc. The agent system itself communicates locally with a service centre which offers information about services available locally or distributed in the entire agent environment. It supports service-oriented trading and comprises an agent directory which for instance allows agent tracking.
The Communication Facilities (CF) are a generic component to provide support in a wireless environment. Its functionality can be sub-divided into three categories: network switching, TCP/IP optimisation and location awareness. Network switching enables a device to move seamlessly from one network to another. TCP/IP optimisation changes the working parameters of the TCP/IP protocol stack. Location awareness provides the mobile agent with information about the current geographic position of its host and some other information.
Figure 26: The AMASE system architecture
The AMASE project has therefore introduced the concept of an agent package. An agent package is a set of agent classes required to perform a specific task. This includes classes for mobile agents and classes for system agents. Thus an agent package is the equivalent of a programming language module (e.g. a Java package) in the agent world. The already mentioned Primary Telecommunication Services (PTS) agent package gives agents access to telecommunication services like SMS or Fax.
Typically this is achieved by means of a system agent which either connects directly to the associated internet-based services or which controls a modem that gives access to them. When a PTS package is installed in the agent environment, the responsible system agent announces its availability to the agent directory. Other agents can ask the directory about the offered service and have the associated system agent send their SMS or Fax messages.
In the AMASE environment, we have realised the following supporting agent packages:
List of agent packages:
|
Package |
Purpose |
|
Primary Telco. Package |
This package gives access to telecommunication services like GSM SMS or Fax. |
|
Secondary Telco. Package |
In the near future this package will allow access to GPRS or UMTS-based services. |
|
Agent Launcher Package |
This package provides a generic way of offering a list of available agents and for starting associated agent-based applications. |
|
Kindergarten Package |
Offers mobile agents the service to wait until a specific agent system (re-)connects to the network or until a specific user logs on again. |
|
User Profile Package |
This package allows storing user related information (e.g. GSM phone number) or user preferences in the LDAP directory. |
|
Network Awareness Package |
A set of agents allowing mobile agents to access information about the current network QoS. |
|
Location Awareness Package |
The set of agents required to determine the location of a mobile device. |
|
Failure Notification Package |
Provides system agents which store error reports and other tracing information about a mobile agent so that agent-based applications may later retrieve the failure reasons. |
In the context of the project the Alpha Credit Bank in Greece granted the project members access to the Alphaline home-banking services which may be accessed via a dedicated server's API. It allows customised client applications to invoke the basic Alphaline banking services, and used with an agent paradigm allows for rapid introduction of new services to the user.
Figure 27: Architecture of the AMASE application
The architecture of the AMASE application is partitioned in two systems: the "External Banking System" and the "AMASE Agent Environment" -as well as two management domains: the "Banking Domain" and the "User Domain". Figure 27 depicts the agent-based architecture for the case of a single user interacting with the application.
Within the demonstrator's design, special respect was paid to user mobility, disconnected operation, user reachability, and automated notification. Thus the implemented services are context-aware. They may use the information contained in user profiles and supporting databases to locate currently used terminals and users at their respective geographic location. Before migrating to the user, agents have to specify their migration policy. This includes negotiation of the resources (processing power, display, number of children to be created, etc.) they intend to use on the destination platform/ device. Furthermore, agents can adapt according to the currently provided network QoS by using different interaction schemes with the mobile user.
Three out of the available services are being implemented within AMASE:
In particular, the two latter services exploit the flexible AMASE notification scheme which tries to reach the user at any time, even if he or she roams between networks, turned off the request issuing device, or switched to another device of different type and location (e.g. office PC versus PDA).
For further trials a distributed test-bed was set up at different locations of AMASE partners in Europe. It comprises systems in Greece, Rumania, Germany, France, and Great Britain. Most of the test sites are connected through the Internet. Some are behind firewalls and are thus only temporarily participating in the agent environment. The test-bed is used for technology trials including benchmarking activities as well as for further evaluation of the AMASE demonstrator.
As can be seen from many market surveys and press announcements the number of mobile devices like notebooks, PDAs and cellular phones rapidly increases. However, currently most services require that the user who wants to access a net-based service have dedicated machines located in a fixed network and that he/she stays connected until service results become available. Regarding this mismatch between user mobility and service access, mobile agent technology offers added-value: agents are proactive and may work without permanent connection to users and services. They may also be personalised according to user's needs, e.g. in terms of when (i.e. time) a user may be reached where (i.e. device, network). An example scenario here is the travelling user who receives the results of their agent-based application on arbitrary devices in arbitrary networks.In order to enable such a scenario in a broad application community the following requirements must be fulfilled:
Within AMASE the first requirement is achieved by an agent system launcher which alleviates installation and startup very much. On "empty" devices only a small launcher must be installed which will download and then start an optimally scaled AS on the respective device. This AS will properly match the device's hardware and software resources, e.g. in terms of GUI, supported processing power, etc. If new components of the AS become available or if the device's resources change the launcher may update the AS accordingly, else it will just start the existing AS.
Concerning the customisation and creation of service access modes a graphical editor is being developed which runs on the broad range of supported devices including notebooks and currently the Psion 5MX pro PDA. This editor allows the user to set personal preferences like when he/she may be reached best on which device. Besides this new application, others may be created by means of existing building blocks in a workflow-style manner. For instance, a simple new money transaction might consist of the following blocks:
once the transaction has been opened, the money will then be transferred from one account to another. If the user is still available on the issuing device the result will be displayed there, else it will be transmitted to another device. Then the workflow terminates.
Summarised this approach gives all, but especially the non-sophisticated user, easy and convenient means to access to nearly any net-based services.
As far as location awareness is concerned this is achieved by means of either connecting to GPS devices (Global Position System based on satellites) or by exploiting location services as these are available in UMTS. In conjunction with naming conventions, as they are used in the Internet, this enables agents to locate their users, and applications to behave according to a user' respective geo-location, e.g. by providing hotel information for the current location in an unknown city. In the near future location aware applications and services will gain more and more significance as it can be seen also from the US government's decision to include GPS functionality into future cellular phones.
By means of the outlined functionality and tools highly mobile users may roam between networks and devices and issue personalised, proactive autonomous service requests such as a stock market monitor without becoming "out of reach" for result delivery and subsequent interaction. This is the basis for a whole range of new future services and applications.
With particular respect to flexible working methods the AMASE project provides basic techniques and solutions giving mobile users easy and personalised access to web-based services. The key impacts are the following:
This is achieved by providing a scalable runtime environment for mobile agents fitting into various types of mobile devices, especially notebooks and PDAs which now provide access to net-based services even via third generation mobile networks. The switching between available networks is transparent and may be optimised according to QoS including cost constraints.
By means of mobile agents which try to find their user irrespective of his or her current position in order to get further instructions or to deliver results there is a substantial increase in user reachability.. This is further emphasised by providing additional notification mechanisms like email, Fax and Short Message Service (SMS).
The convenience and capabilities of the access to net-based services are much improved. Users may download up-to-date application parts and specify where and when they may be reached or how they want to access a service. For instance, a service request with special user preferences may be issued on a device in the office whilst the results will be delivered to a home device as soon as they become available.
The feasibility of the agent-based AMASE approach is demonstrated by providing access to real-life banking services (see chapter " Agent-Based Applications"). Although no standardised agent system is used a contribution from this is expected to impact ongoing standardisation activities (OMG MASIF). Furthermore, the integration of the WAP standard is being exploited.
Hence AMASE contributes to the general ACTS and IST-programme objectives of user-friendliness, accessibility, convergence and quality of services of the Information Society with respect to the provision of scaleable, mobile services.
One solution to meet these requirements could be UMTS, which is the upcoming 3rd generation mobile communication network. UMTS will cause a diversification of available network services and mobile terminals by providing a variety of services and flexible access for the mobile user.
Summarised, the future research aspects are to create advanced scalable, modular communication systems together with easy and customised access to net-based services and applications for everybody from everywhere at any time.
The ACTS AMASE project focuses on developing a mobile agent platform taking wireless networks into account. An existing agent system was successfully enhanced according to research issues focussed on mobile operation and highly mobile users roaming between networks.Currently three different networks including Ethernet, WaveLAN and GSM are supported, and switching between these is performed transparently during system operation and according to QoS issues. The enhanced agent system scales onto different device classes ranging from workstations/PCs down to PDAs. In addition agent-based applications have to negotiate their resource requirements during runtime, and they may benefit from a range of databases which are used for instance for locating services and users. Access to these databases may be based on trading. Furthermore, both applications and the underlying agent systems are protected against each other by means of an extensive security concept.
The project has demonstrated that mobile agent-based applications can easily exploit telecommunication services like Fax, GSM SMS or e-mail. With the ability to customise existing applications, the developed system helps in providing very flexible and extensible services for mobile users. For the unsophisticated users this task is greatly alleviated by means of a graphical editor used for creating applications in a workflow-style manner out of a set of predefined and easily customisable components.
Experiences within the project have shown that in order to exploit the full potential of a mobile agent system, developers and system managers need more sophisticated tools for development, installation and monitoring purposes. Furthermore, in today’s world wide web, most of the services are offered for the human user, and they are barely usable for automated agents. We hope that this will change with the semantic capabilities of XML.
As can be easily anticipated the acceptance of mobile agent technology strongly depends on the number of agent-based services available. Within the AMASE project it became also evident that future services must be much more adaptable to personal user preferences as well as a user's current situation. This includes several different parameters like a user's current geo location and the requested service, his or her respective device, the available network connections and their QoS parameters. Together these parameters create a user's working context. Such information should not be given to arbitrary servers in the Internet. Thus we expect users to select dedicated service providers with whom they will establish a trust relationship enabling access to specific elements of the services within the context of the trust relationship. This corresponds to the well-known trend that controlling the dissemination and usage of private information becomes an increasingly important issue in a networked world.
Distributed computing in the world of cellular or wireless networks is inherently different from standard Internet computing where permanent connectivity can be safely assumed. In the world of mobile networks, this assumption is not valid. The mobile agents paradigm is better suited for this world as the traditional client-server approach. This holds especially true for (a) disconnected operation, (b) dynamic extension of functionality, and (c) location-specific operation.
Nevertheless we do not argue that mobile agents will replace client-server systems. There are many scenarios where these systems provide the required functionality in an easier or more performant way. We are supporting an emerging opinion in the mobile agent research community that mobile agents will complement current approaches like client-server, three tier applications, Web-based approaches or CORBA. Thus, in the beginning, the application of agents will most likely be restricted to closed environments where a group of privileged users has access to a set of well-known agent-based applications. This at least will alleviate some security issues. As agent technology matures more and more general purpose applications can be expected which will be available in more open environments until they finally become available for the Internet. This evolution is quite similar to the development of applets and servlets which can be seen as very simple mobile agents and which become increasingly popular in the Internet.
Diane Brady "The nomad shall inherit the airport lounge", in Peter Coy, Neil Gross: "21 ideas for the 21st century", Business Week - European Edition, August 23-30, 1999, p.80fACTS AMASE project homepage,
http://b5www.berkom.de/AMASE"AlphaDirect Server - Programmer's Guide", Alpha Credit Bank
Gartner Group: "Computer Usage in the Year 2003 and beyond" (in German), Gartner Group ITips, March 1999
GSM Association:
http://www.gsm.orgNokia 3rd generation:
http://www.nokia.comACTS: Next Generation Internet in Europe (ISBN 3-00-004250-4)
Björn Schiemann, Birgit Kreller, Matthias Reich, Ernö Kovacs, Klaus Röhrle, Hong-Yon Lach, Anthony Sang-Bum Park, Steffen Lipperts: "Agent Environment Specification - Part B", AC346 - ACTS Project, Deliverable 01b, 1998.
Domique Carrega, Björn Schiemann, Dana Trifanescu, et al.: "Delivering Value-Added Banking Services for Mobile Customers with the AMASE Agent Environment"; Proceedings of the ACTS Mobile Summit, Sorrento, Italy, June 8-11,1999.
Björn Schiemann, Ernö Kovacs, Klaus Röhrle: Adaptive Mobile Access to Context-Aware Services; Proceedings of the 3rd International Workshop on Mobile Agents, Palm Springs, USA, October 1999
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