When to use <abbrev> tag?

["David O'Brien" <daobrien@redhat.com>]

Greetings
We use DocBook 4.5 to produce documentation for computer software. I'm 
looking for advice on when I should use (e.g.) <abbrev> tags and when I 
should use something more specific (and complex). For example, HTTP, 
SSL, NFS, and LDAP are all abbreviations, but they are also protocols. 
MIT is both an abbrev. and an orgname. There are many examples. I don't 
have a clear argument why I should use one or the other.

The discussion becomes more interesting if you think about (e.g.) NFS 
and SSH because they could be categorized as protocols, services, etc. 
I've been trying to tag them by context; i.e., am I referring to xyz as 
a protocol, a resource, or what? I've had some success with this, but at 
the same time, "xyz" is *always* an abbreviation.

All suggestions welcome. Thanks a lot.

-- 

David O'Brien
IPA Content Author
Red Hat Asia Pacific

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