From looking at some of the posts about other routers, I suspect it has to do with using the cisco management software they bundle with it. When you run it, they want you to subscribe to their parental control service and the Access Restriction tab is hidden somehow when you use the browser interface.
I'd be interested in hearing from someone who know that this is in fact the case, especially with resptect to this model. I see in the release notes for this router than one of hte early updates included "support for network defender". If by "support", they mean they disable functions and try to get you to subsribe to a service, I think that's pretty cheesy. I selected this model because I looked at the online documentation and it had the same access restriction functionality I"ve seen other other linksys routers.
