David Fowler has a table for us:
The question of encryption seems to be coming up a lot recently. I’ve had a number of people asking me about how to go about encrypting SQL Server.
SQL can encrypt our data at a number of different levels and gives us a quite a few options when doing so. I want to use this post to put together a matrix so you can easily see which method of encryption suits your purpose. I’ll look in to each method in more detail in a future series of posts.
Click through for a rather comprehensive table and remember that “several of these all at once” is usually the correct answer for which to choose.