Problem. The World Wide Web has greatly increased the amount of information available on-line, but obtaining the right information at the right time in the right format is still beyond the state of the art, since there is no higher-level Web-wide information model and existing Web tools do not adequately address the problems of filtering, aggregating and disseminating this information. Information must either be accepted "as is" or converted and delivered by manual means or a complex programming process requiring specialized skills. “Portal” or “channel” technology is intended to provide customized information delivery, but current technology has limited modeling and manipulation power, its centralized architecture does not make best use of network computing capabilities, the resultant channels are not resilient to denial of service attacks or component or network failure, and since channel composition is not exposed, collections of channels cannot be optimized to reduce processing and bandwidth costs.
Objective. Develop smart data channels (SDC) technology to allow the flexible and efficient creation of information channels through which information flows through the Web from data sources to information consumers.
Approach. SDC uses and augments existing Web technology and standards to reach the largest market at the least development cost and risk. In particular, SDC is based on XML and XSLT, with the current implementation being in the Java programming language. Details. In SDC, desired channel content is specified declaratively rather than procedurally. This allows the type of information flowing over the channel to be externally visible, which in turn makes it possible to define new channels in terms of existing channels, to use type matching to determine potential information sources for channels, to switch to alternate sources when primary sources become unavailable, and (ultimately) to optimize collections of channels to reduce processing and/or bandwidth costs. SDC operators move information and allow channels to be combined and tailored to individual needs. Flow control on a channel allows specification of update policies for the delivered pages (i.e., the conditions under which changed page content is delivered). Profiles allow customization of output and delivery based on the type of the display hardware. Channels can be automatically parameterized based on user characteristics such as location (e.g., deliver maps for where I am right now).
Demonstrations. SDC was initially demonstrated to the Space and Missile Defense Command under a Ballistic Missile Defense Command SBIR Phase I. A substantially improved XML-Java version was demonstrated to the DARPA CoAbs Program as part of the OBJS Agility project.
Grid. Developed mostly under SBIR, SDC is not currently tied to the CoABS grid. At present, it represents a different sort of grid/infrastructure implementation, also capable of interoperability with agents, the CoABS grid, or DAML.
Plans. (a) Improvements: performance and reliability, design and implement better interfaces for channel creation and subscription. (b) Define a more robust SDC algebra for specifying channels. (c) Integrate SDC with Traders to allow channels to be located and matched more effectively. (d) Develop optimization strategies to conserve system resources. (e) Upgrade from XML to DAML.
Technology Transition. SDC will be used as a test application for the DARPA DASADA program, possibly also as an architecture description configuration representation. NIMA has shown interest for routing map products through processing stations to DoD customers. We are also seeking commercial support for further development.