[xwiki-users] Access Rights by Network

Hello, I am trying to control access to XWiki based on the incoming IP address. Currently, I have the wiki set up to allow view access to everyone including guests, and write access to logged in users. This works fine on the local LAN, but I'd like to allow external users access to the wiki as well. I would like to force users accessing the Wiki from outside my network to log on before they can view Wiki pages. There doesn't seem to be any build in mechanism for filtering access by IP. Is there a work-around that would let me to this? Thanks.