Dynamic application composition for distributed systems

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The software that most people use is designed and packaged to run on a single device (e.g. a spreadsheet running on a personal computer). Exceptions to this approach are normally restricted to high-end scientific and business applications that do not run on conventional desktop machines or personal computing devices (e.g. cell phones, PDAs, etc.). This "standard" programming approach implicitly assumes an underlying model of computing where everything is done on a single, general purpose computer. This model, however, is quietly fading as new mobile and embedded devices become prevalent. Increasingly, such interconnected devices are collaboratively involved in computations. Among the multitude of examples of this phenomenon are Peer-To-Peer file sharing applications and multi-user gaming (at the large scale) and multimedia tools running on iPods, cell phones, etc. (at the small scale).   In this proposal, I argue that continuing to assume that programs should be monolithic entities running on a single machine and licensed to specific individuals is overly restrictive and should be replaced. I suggest an alternative model based on executable components (i.e. pieces of runnable programs performing self-contained functions) that may be dynamically "composed" to create applications on the fly that are tailored to specific user and environmental characteristics. Such dynamically constructed applications can be run more efficiently both on and across a wide range of interconnected devices. For example, consider a scenario where a user needs to edit a document while travelling using a mobile device with limited capabilities. Normally the user would have to pay for and pre-install a large, complex and costly application to support editing the necessary document on the mobile device. In my proposed approach, only the necessary parts of the software would be dynamically composed on demand to run on the mobile device (and, if necessary, on one or more nearby machines offering compute services). Further, thecomposed software could be tailored to suit the small screen size and limited reliability of the device's wireless connection to the Internet.