bind accounts to the services

[Cristian Del Carlo <cristian.delcarlo@osratoscana.it>]

Hi,
I  use my ldap service to authenticate the user  on many services as squid,samba,apache ecc...
I would want to use it to allow or deny  the services  to the  users .
For example to user A is allowed to use samba but isn't allowed to use  squid. 
How is possible to bind the user with the service?
I think to use a group for each services and allow or deny  the access to the services with the groups ...it is corret?
Thanks for yours help.
Best regards,

Cristian Del Carlo