it is my opinion that this is what DNN is really best at doing.  I know people have varying opinions regarding child portals, but in my seven years plus, I've really found that the replication via child portal management is what makes this product a standout.

I have found that it's very important to pick the modules being used, and to consider how many administrators there will be on each portal.  I would look at seeing what could be handled globally, within skins, through to ensuring the server has enough ram and the application pool resources allow for not the browsing and viewing, but the administration. 

It is my opinion that the peak requests going back to the sql server are when in administration mode, checking permissions. 

I would also be really thinking out what modules are going to be added to the site and how to minimise where possible.

I agree with the costing - I'd love to be able to recommend the Professional version but with the 2k per annum price tag and no backward compatibility should you decide to go community, I'm still not fitting in the market of having this as part of my business model. It is supposed to have more performance features than the community version, but I've found that a well setup server with plenty of ram, a big sql server with plenty of resources, and it's own application pool, then use your skills you have with the seven years of learning, and I think you'll be perfectly fine.

It also is important to know that once individual portals have over 400 pages, then it can become a logistic nightmare, which is why we choose our modules carefully.    I also feel that any xml based modules that have custom configuration really need to be analysed as they can give you a huge performance hit.

You see it's not the visits as unauthenticated users that I believe gives grief, it's the amount of administrators. If you have 125 administrators logging in at once, with complicated modules that are the undoing of DNN.

Hope this helps you in your decision process.

Nina Meiers

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