On Tue, 21 Apr 2009, Eric Lease Morgan wrote:

> On Apr 21, 2009, at 10:40 AM, Mike Taylor wrote:
>
>> I, and most of the people I've worked with, have been using the terms
>> "metasearch", "federated search", "broadcast search" and "distributed
>> search" synonymously for years.  Have they now settled down into
>> having distinct meanings?  If anyone could summarise, I'd be grateful.
>
>
>
> Yes, to me, the quoted phases above are synonymous.
>
> But I believe we are also seeing a new type of index manifesting itself, and 
> this new index has yet to be named. Specifically, I'm thinking of the index 
> where various types of content is aggregated into a single index and then 
> queried.

[trimmed]

Wouldn't this just a "union catalog"?

Now, you might want to differentiate between what's being joined -- 
multiple types of content all at one location vs. the same type of content 
at multiple locations.  (or both varying).  I don't think any of the terms 
mentioned really show that distinction, however.

We normally use 'heterogeneous' in the science to refer to more than one 
type of data object, but it's really superflous in our field, as there are 
very few forms of federated search where you'd have two repositories of 
similar data -- maybe for browse objects (movies, pre-rendered images), 
but those are typically viewed as supplementary metadata, and not the 
object of primary importance.



-----
Joe Hourcle
Principal Software Engineer
Solar Data Analysis Center
Goddard Space Flight Center