A. the routing protocols being utilized in the network
B. the applications utilizing the network
C. the traffic destinations
D. network addressing scheme
E. cost of implementation
F. the amount of the control needed of the resources

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 attempts to deliver a level of service based on the QoS specified by each packet