Part 3 - Site Collections
Continuing on from Part 1 and Part 2 where I discussed Zones, Authentication providers and Policy, this time I would like to discuss Site Collections.
A site collection is a container, it forms the basis of an information architecture where you can create sub sites to build out your information architecture.
Windows Sharepoint Services (WSS) allows the user to create one site collection, that is all of your content will be housed in a single site collection.
MOSS takes a different approach and allows you to create as many site collections as you need, if you turn on self service site creation for team sites, then every site will be a site collection. Even the My Sites are in fact a site collection.
Using managed paths, you can create site collections that form parts of your information architecture.
So what are the benefits of a site collection? The first is distributed administration, each site collection can have different administrators, the other big features are a separate recycle bin and the ability to enforce a quota (as well as the features not covered here).
Each site collection is an isolated collection of sites, you can't use the content query web part to roll up content across site collections (although you could use RSS feeds to do this). This might sound like a bad thing, but lets consider it with an example.
From Part 1 we put forward a scenario where we have staff members and external people accessing a portal, both of these groups need to view different information depending on who they are. Lets assume we had one single site collection, without item level security (which isn't an out of the box feature) all users could see information they shouldn't. Or assume we did have item level security, it would only take a simple mistake to assign the wrong permissions for information to leak.
It might sound like a good idea to have a single site collection, but after you think about it a little more it becomes obvious that it doesn't work when you get past a simple implementation (like what WSS is designed for).
Looking at the reference diagram from Part 1, we see that Microsoft has indeed separated the partner content and internal content into separate site collections.
Monday, May 12, 2008 9:56:25 AM UTC 
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