About Intelligent BW

In today's Internet, information services such as WWW, Gopher, WAIS, etc. are oriented towards a reactive model: the Internet and its servers transport and respond to individual requests. Currently, those requests are serviced by conventional client/server systems. With the evolution of these systems, the expectations of the user interface are changing from an Internet model of "point, click, and wait" to an interactive "point, click, and action" behavior.

Even with existing client/server implementations, the Web can use tens of megabits of bandwidth to provide an interactive response time. Reaction speeds near 100 milliseconds (0.1 sec.) are required for transparent real-time interactive use. Given simple files in the 10 Kbyte range, this requires 0.8 Mbps, exclusive of transaction processing, file retrieval, and intermediate buffering. Current measurements of Web logs indicate that simple hypertext files are near this size; graphic files are typically 60-100 Kbytes or larger, and it is not uncommon for a single page to incorporate tens of such images. Bandwidths near 5-10 Mbps would be required.

We expect available end-user bandwidth to be in the 14 - 28 Kbps range for conventional modem access, and 128 Kbps for ISDN in the near future: all insufficient to support interactive access. We are developing techniques to adapt client/server hypermedia systems to the available bandwidth, and to use idle bandwidth between user requests to reduce the bandwidth required for real-time interactive access. Such techniques also adapt to other overall system parameters to optimize performance proactively, rather than waiting to react to user requests. Such proactive mechanisms are also suited to supporting emerging information services such as satellite, radio, and cable, as well as supporting mechanisms for replication in support of reliability (as above).

More information about intelligent bandwidth: