I've seen several large companies that offer individual webpages or "websites" for their associates, within the companies main domain. Once created, they have unique URLs something like johndoe.companyXYZ.com or companyXYZ.com/johndoe. Then, the associate can login and customize their page.
I would like to have something similar, but don't know where to start.
To offer something like this, would it need to be completely built from scratch? Or is there a CMS that can do this out of the box?