ACS 5.3 child domain

[Carl Steben]

Hi .. is there a way to restrict AD to a child domain ?

our business is part of a huge forest with multiples domain. 

[Nicolas Darchis]

You need to define your requirement better.

You want to restrict ACS to authenticate only users with a child domain, is that it ?

Then simply by ACS to that child domain and write your access policies to verify that the users belong to that child domain. Then you're good to go