catalog-level security

[Tennessee Leeuwenburg <t.leeuwenburg@xxxxxxxxxx>]

Hi,

We would like to implement catalog (or even dataset) level security on 
our external server. I'm unsure how to do this. I understand how to 
secure a particular web application, but I don't want to run a separate 
server instance for every single user!

Is there a recommended way?

Cheers,
-T