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.
Figure 3. Storage Engines.
Contents
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