1.  Field
This application relates generally to communication and more specifically, but not exclusively, to access control. 
2.  Introduction
A wireless communication network may be deployed over a defined geographical area to provide various types of services (e.g., voice, data, multimedia services, etc.)  to users within that geographical area.  In a typical implementation, access points (e.g., corresponding to different cells) are distributed throughout a network to provide wireless connectivity for access terminals (e.g., cell phones) that are operating within the geographical area served by the network. 
In general, at a given point in time, the access terminal will be served by a given one of these access points.  As the access terminal roams throughout this geographical area, the access terminal may move away from its serving access point and move closer to another access point.  In addition, signal conditions within a given cell may change, whereby an access terminal may be better served by another access point.  In these cases, to maintain mobility for the access terminal, the access terminal may be handed-over from its serving access point to the other access point. 
As the demand for high-rate and multimedia data services rapidly grows, there lies a challenge to implement efficient and robust communication systems with enhanced performance.  To supplement conventional network access points (e.g., macro access points), small-coverage access points may be deployed (e.g., installed in a user's home) to provide more robust indoor wireless coverage or other coverage to mobile units.  Such small-coverage access points may be referred to as, for example, femto access points, femto cells, home NodeBs, home eNodeBs, or access point base stations.  Typically, such small-coverage base stations are connected to the Internet and the mobile operator's network via a DSL router or a cable modem. 
A small-coverage access point may support restricted access.  For example, access at a given access point may be restricted to those access terminals that are a member of a defined group (e.g., the set of access terminals belonging to the owner of the access point).  In some cases, an access point may provide different levels of service to different access points.  For example, a so-called hybrid access point may provide one level of service (e.g., preferred service) for member access terminals and a different level of service for non-member access terminals.  In view of the above, there is a need for effective access control for these and other types of access points that support restricted access.