Pallapa Venkataram
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Future Plans

Launching a National Initiative on Ubiquitous Computing

    The world today is replete with a large number of gadgets which in a broad sense are disconnected. Such a technological mode will reach its saturation soon. Ubiquitous computing is a world wide initiative started roughly 4 years ago to resolve this practical dilemma; Project Oxygen, Aura, Portalano, are testimony to this international initiative.

Very succinctly, ubiquitous computing will create a ubiquitous environment that combines processors and sensors with network technologies (wireless and otherwise) and intelligent software to create an immersive environment to improve life. It is imperative that we India too become part of the leaders who are developing this technology and impacting the society as whole. Such a broad initiative has to be a cooperative one; in the initial phase we will have six institutions participating in this endeavor (IISc, four IITs, IIIT-Bangalore). As we progress, other IITs, NITs and other institutions will be part of this endeavor. Our mission, goals, project path, and deliverables are mentioned in the following sections..

Developing low-power protocols and services for wireless communications

    The implementation of small, mobile, low-cost, energy conscious devices has created unique challenges for today s designers. The drive for a miniaturization and inexpensive fabrication calls for an unprecedented high level of integration and system heterogeneity. Limiting battery lifetimes make energy e ciency a most critical design metric and the real time nature of applications impose strict performance constraints.

To meet these conflicting and unforgiving constraints, we must rethink traditional operating system approaches in embedded wireless communication. General-purpose operating systems developed for broad application are increasingly less suitable for these types of complex real time, power-critical domain specific systems implemented on advanced heterogeneous architectures.

We propose to design low-power protocols and services for this specific requirement.

Multimedia Information Systems on Wireless LANs

    Like LAN interconnect multimedia will grow from humble beginning into a robust, wide-area industry. With advent and the forthcoming of high speed networks, we anticipate distributed multimedia applications will become a common place on the desktops. These applications that could be executed locally or remotely, and could access and retrieve data as text, graphics, digital audio and video over the network.

      General distributed systems mostly rely on a client/server communication model. A client will make a request for a service; the network will communicate the request to the server and the subsequent reply from the server back to the client. It is envisaged that the trading distributed environment must be enhanced to provide support for more complicated multimedia services such as voice and video. The distributed multimedia systems are suited to the human being's complex perception, communicating behavior, and way of acting. It will not only provide communication capabilities and information sharing between people, irrespective of local and time, but also easy and immediate access to widely distributed information banks and information processing centers. This will be possible on the basis of a variety of information types.

      We propose to design and develop a distributed multimedia system which has more flexible approach on
the following:

  • Continuous media- the most important characteristic of multimedia to support video, voice and raster image data.
  • Better QOS (Quality of Service)
  • Single radio channel is used for many multimedia applications.
  • To adopt to the slow speed existing I/O Devices.

AI Applications in Distributed Systems Design Issues

      Distributed Systems, such as those which contain heterogeneous operating systems, are crucial to the design and development of new and innovative products for the future. Differences in Operating Systems will continue to persist because of the variety of hardware in the market-place, each with software that provides a vendor with a product having a customerized or competitive edge over the other. The design and implementation of such systems pose many problems. As is pointed out in, even in heterogeneous systems, operating systems of the present generation provide little or inadequate support for local area networking and distributed processing. Non-uniformity in the characteristics of current operating systems has posed additional complexity in the development of heterogeneous local area networks (LANs). This has good reasons to incorporating AI techniques into the design of various aspects of these systems. Notable among these efforts is the knowledge-based distributed operating systems.

     Here we propose a revolutionary approach to design distributed systems using object-oriented techniques that support local area networking and distributed processing. In this work we concentrate on how AI technique can be applied to enhance the design of the front-end subsystem of each host in a distributed environment. The functions of the front-end subsystem that will be addressed are the following:

  • User interface management
  • Interconnection in the case of heterogeneous systems
  • Security

Automated Network Management System

     In computer networks the prevailing trend for several years has been the creation of internets, networks consisting of a (possibly large) set of networks. The size of internets and their geographic distribution has made managing them a necessary and complex task.

     We propose to develop an automated network management system for assisting and controlling complex internets. The ANM system provides an integrated set of tools for real-time monitoring, control, and analysis of internets consisting of diverse network entities such as internet gateways, packet switching nodes (PSNs), packet radios, and hosts. It can reduce maintenance costs by providing capabilities such as fault isolation and alarm generation, so that the network operators can effectively and efficiently monitor and control networks. ANM also provides advanced data gathering, analysis, and presentation tools that enable the network analyst to understand better the behavior of the network, and to enhance network performance.

      The proposed ANM system to provide the management facilities (or services) that are defined by the ISO Standards. They are:

  • Fault management- detecting, diagnosing, and recovering from network faults
  • Configuration management- defining, changing, monitoring, and controlling network resources and data
  • Accounting- recording usage of network resources and generating billing information
  • Performance Analysis- tracking current and long term performance of the network
  • Security- ensuring only secured and authorized access to the network management system and the network resources
  • Resource Management- supporting directories for management network assets and user information

An Interactive Protocol Tester

     An interactive Protocol Tester for design, simulation, verification, and synthesis of multimedia protocols

     A user-friendly graphical tester for the design, verification, simulation, and synthesis of protocols based on an interactive tool for pertinent and state diagram designs, special features of this tool are: the capability of modeling both control and data flows, reduction and analysis, simulation of network behavior and performance, coding, synthesis, animation and flexible design.

     A protocol correctly designed should satisfy the following logical properties

     1) boundedness 2) deadlock-freeness 3) proper termination 4) completeness, and 5) liveness

     Protocol analysis refers to the validation of these logical properties after designing a protocol.
     Protocol synthesis is a procedure to design new communication protocols, using certain rules, correctly and systematically.

Location Management in Mobile Networks

      Mobile computing represents a new paradigm that aims to provide continuous network connectivity to users regardless of their location. To realize this aim, it is necessary to design distributed algorithms that explicitly account for host mobility and the physical constraints associated with such networks.

      To facilitate continuous network coverage for mobile hosts, a static network is augmented with Mobile Support Stations (MSS) that are each capable of directly communicating with MHs within limited geographical area ('Cell'), usually via a low-bandwidth wireless medium.

Distributed mobile environment

      A mobile network is composed of a fixed network and a wireless network that interact with each other. The wireless network consists of mobile hosts which have the capacity to exchange messages with a mobile support station. The mobile host can communicate with a mobile support station that is within a short distance from itself. The mobile host may move from one cell to another while communicating with the fixed network (or with another mobile host through the fixed network). At every instance the communication of the cell in which the mobile host is currently located.


      The critical and challenging problem of mobile computing is how to cope with the special characteristics of the mobile wireless environment, to make balanced usage of computation and communication, and to take advantage of and support the user's mobility, via:

  • Location-aware information
  • Knowledge of a user's mobility behavior,
  • Mobility management support.
     These allow the systems to dynamically configure themselves, and to make applications aware of the characteristics of the dynamically changing connections, such as bandwidths, latencies, etc., so that they can be adapt as necessary.

      Mobile radio channels are severely affected by time-varying losses due to distance, shadowing (blockage due to buildings, trees, etc.,) and multipath fading. While the variation in the losses due to distance and shadowing is relatively slow, the variation due to multipath fading is quite rapid.

      In the proposed scheme we design an optimal location management of mobile hosts such a way that there may not be losses due to fading. We also look at the slow fading and relocation of nodes during rapid fading environments.