A.Cisco IOS gateways provide services such as address translation and network access control for the devices on the networl
B.Cisco IOS gateways provide services such as bandwidth management and accounting
C.Cisco IOS gateways provide media termination and signal translation between the public switched telephone network （PSTN） and IP networks
D.Cisco IOS gateways provide zone management for all registered endpoints in the network

A.FIFO queuing is only appropriate for slower serial interfaces
B.weighted fair queuing is the default queuing mechanism used for all but slower than E1 rate interfaces
C.only one queuing mechanism type can be applied to an interface
D.weighted fair queuing does not require the configuration of access lists to classify traffic  
E.flow-based weighted fair queuing provides for queues to be serviced in a round-robin fashion