Replacement for solaris XDM on RHEL7

Hi
I want to move a XDM service running on Solaris to RHEL7.
The Solaris XDM service allows connections and users to be able to choose depending upon hosts list a server to connect to. This is listed in the Xaccess as %hostlist etc

RHEL7 no longer uses XDM so I would like to know if it is possible for this to be implemented in RHEL7 and how it can be done.

cheers