Web-related standards today cover only the syntax of presentation and file location. The effort described above absolutely requires ways to encode semantic information about the contents of pages and other sources of information available on the network. The trend towards the use of Java in Web sources has the potential to greatly exacerbate the problem of content opacity, since the information that a site provides may be generated by a program and not be statically present and available for analysis by, say, an automated content modeling system. With potentially unlimited areas of information available, users will have to be provided with interactive assistance in the process of query creation. Widespread acceptance of and careful adherence to proposed content encoding standards will be required before such a distributed system could be useful on a large scale.
Information sources change on a routine basis.
Regular maintenance is required throughout the network of sources. All the barriers noted in the previous section will have to be overcome for the Universal Information Base to become feasible. In more limited contexts all the elements of a solution are already being addressed. Self-interest among information providers as a motivator for adhering to standards and indexing procedures. If they don't - it will be as though their information were never put on the net, as far as most others will be concerned.