MobiCom '95 Tutorials


Mobile Computing: Issues, Challenges and Solutions

Tomasz Imielinski
Rutgers University, New Jersey, U.S.A


User mobility, limitations of battery technology and widely varying bandwidth conditions are the main new factors which will drive application and systems software for mobile computers. In this tutorial we will discuss in more detail how each of these factors is going to influence software development for the future PCS environment. We will begin by reviewing the basic system models ranging from Xerox's vision of ubiquitous computing, through the Infopad's model and mobile "walkstation" model. We will also discuss different families of possible future applications. Next, we will address specifically the major software issues such as:

  • Primitives to develop location dependent applications

    The main middleware primitives to built applications which depend on user location such as location dependent "Mosaic like" information services. Flexible solutions dealing with widely varying concepts of location (from macrocells through picocels to the exact, GPS determined, location). Map centric applications. The concept of nearcasting to discover the nearest (to the client's current location) information services on the network.


  • Client Server computing in mobile and wireless environments

    New information dissemination modes based on periodic broadcasting as well as interaction of caching and mobility. The impact of client's disconnection on file and database system access. The Client-Proxy-Server model in which mobile clients interact with remote servers through local agents, called proxies. The concept of environment aware clients which adapt to changing conditions in the local environment including bandwidth, power conditions and tarriff structure (paying per connection time vs paying per packet). Client's interoperability in widely varying environments ranging from wireless LAN to low bandwidth outdoor radio.


  • Energy Efficient Software Solutions

    Principles behind designing energy efficient application and systems software ranging from scheduling CPU operations for low energy to energy efficient information dissemination protocols.


  • We will also briefly discuss other important issues such as privacy and security in mobile environments. We will conclude with some of our own experiences dealing with the location dependent application design in wireless LAN and CDPD environments.

    The tutorial will be based on the research work at AT&T, Bellcore, Berkeley, Columbia, CMU, Intel, IBM, Rutgers, MIT, Xerox Parc and the University of Washington. The "industry update" will include projects at Motorola, RAM Mobile, RadioMail, ARDIS, SUN and AT&T and others.



    Click here for a biographical sketch.


    Last modified on Friday, 25-August-95 13:57:32 EDT