A Vision for Open Hypermedia Systems Nürnberg and Leggett

4.1.2 Storage Engine
A storage engine entity in our architecture should be interpreted as an entity that provides persistent storage to clients. This is in contrast to previous proposals that discuss the kinds of abstractions these storage engines might or should serve (data objects, links, etc.) We see no benefit in distinguishing among hypermedia storage engines (HBMS's, Hypermedia databases, or other terms applied to such entities), data storage engines, document storage engines, etc., especially from the point of view of defining the OHP. Thus, we try to sidestep the division mentioned above by Wiil and Leggett [1996] between open link servers and open hyperbases. It will be the case in some OHS's that Sprocs talk to "structure-aware" storage engines, while in others, they talk to databases, file systems, or other engines that provide pure data abstractions. Additionally, we intentionally ignore the issue of storage engine "wrappers" as suggested by Wiil and Whitehead [1997] and elsewhere. This is not because we feel the subject to be unimportant or uninteresting, but because it does not seem relevant to the goal of defining an OHP. We suggest that this issue be taken up by the group outside of the OHP discussions.

Analogs to our storage engine entity can be found in any OHS, although as stated above, the issue of structure-awareness varies among systems. Additionally, both current reference architecture proposals have clear analogs to this entity.

A reference architecture box diagram
Figure 3. Storage Engines.


Peter J. Nürnberg, John J. Leggett
HRL, CSDL, Texas A&M
original page URL: http://jodi.ecs.soton.ac.uk/Articles/v01/i02/Nurnberg/refarch_ent_store.html