A.the DiffServ model requires applications to signal the network with QoS requirements
B.the DiffServ model can be used to deliver QoS based upon IP precedence， or source and destination addresses
C.the DiffServ model requires RSVP
D.the best effort model is suitable for applications such as file transfer and e-mail
E.the IntServ model requires applications to signal the network with QoS requirements
F.the IntServ model model attempts to deliver a level of service based on the QoS specified by each packet

A.centralized management for autonomous access points 
B.centralized management for lightweight access points
C.centralized management that requires an external AAA server 
D.centralized management with integrated AAA server
E.integration with the Location Appliance to expand real time tracking to 1500 devices for 30 days 
F.integration with the Location Appliance to expand real time tracking to 2500 devices for 30 days