distinguish between a intranet user and remote user

["M.Raghu Babu" <rmovva@waterford.org>]

Hi all,
    Is it possible that I can distinguish between a local user(in my company 
Lan) accessing ldap and others(possible outside my company Lan).  I dont want 
to give the outside user to access some sensitive data.  Is there any way to 
provide acl to recognise the ipaddress to distinguish between the local user 
and the remote user.  Is there anything like IP/Subnet verification.

  	Hoping for a solution.
Thanks & Regards
M.Raghu Babu