The functionality of the Net can be viewed in waves as illustrated above. In the upswing of a wave, the fundamental research is being done for a new level of functionality. Prototype research systems begin in the trough and evolve into mass commercial systems in the peak. The functionality of this wave is then polished and finalized in the downswing period before the start of the next wave. The First Wave was the level of access, of transmission of data. It began with the coming of the ARPANET and evolved through large-scale distributed file systems such as AFS, roughly 10 years on the upswing and 10 on the down.

The Second Wave is the level of organization, of retrieval of information. It began with distributed multimedia network information systems, such as PI Schatz's Telesophy system, which was featured in his invited talk at the 20th Anniversary Symposium for the ARPANET in 1989 as the example of technology which might make possible future worldwide information spaces. That same year saw the initiation of the World-Wide Web project at CERN, which when coupled with the NCSA Mosaic interface became the technology that brought global information spaces to the world at large. As one result of his work on the Telesophy system, Schatz became the scientific advisor for information systems to NCSA throughout this entire period, in both the pre and post Mosaic eras. The information wave took about 10 years to peak and should continue for another 5 in the consolidation phase, through the near future period of distributed objects and Internet-wide operating systems.

The Third Wave will bring the level of analysis, of correlation of knowledge. It will move past search of individual repositories, beyond federation across repositories, to analysis of diverse groups of information across sources and subjects. To develop the new technology needed for this new wave 10 years hence, one needs to begin now so that widespread research prototypes can be available for the new millennium supporting global semantics. In this third wave, the Interspace, there will be distributed services to manipulate concepts across domains just as the ARPANET had distributed services to transfer files across machines and the Internet is having distributed services to transfer objects across repositories. The Interspace environment supports fundamental manipulation of concept spaces: indexing and retrieval, grouping and sharing.