A.End-to-end delay is the sum of propagation delays，processing delays，serialization delays，and queuing delays.
B.Coast-to-coast end-to-end delay over an optical link is about 20 ms.
C.Processing delay depends on various factors，which include CPU speed，CPU utilization，IP switching mode， and router architecture.
D.Propagation and serialization delays are related to the media.
E.Propagation delay is the time it takes to transmit a packet and is measured in bits-per-second （bps）.
F.Serialization delay is the time it takes for a router to take the packet from an input interface and put it into the output queue of the output interface.

A.class-based weighted fair queuing （CBWFQ）
B.low latency queuing （LLQ）
C.priority queuing （PQ） or custom queuing （CQ）
D.Real-Time Transport Protocol （RTP） header compression
E.TCP header compression
F.UDP header compression

A.On each router， under the dial-peer voice 1 pots configuration， add the port fa0/0 command.
B.On each router， under the dial-peer voice 1 pots configuration， add the port 1/0/0 command.
C.On each router， configure dial-peer voice 1 as a voip connection and configure dial-peer voice 2 as a pots connection.
D.Under the dial-peer voice 1 pots configuration， change the destination pattern of 1111 to 2222 on the R1 router， and 2222 to 1111 on the R2 router.
E.Under the dial-peer voice 2 voip configuration， change the destination pattern of 1111 to 2222 on the R1 router， and 2222 to 1111 on the R2 router.
F.Under the dial-peer voice 2 voip configuration， change the destination target address of 10.2.2.2 to 10.1.1.1 on the R1 router， and the destination target address of 10.1.1.1 to 10.2.2.2 on the R2 router.

A.automated alternate routing （AAR）
B.Cisco CallManager Attendant Console
C.real-time protocol （RTP）
D.Survivable Remote Site Telephony （SRST）

A.Use the command ip nbar protocol-discovery to allow identification of stateful protocols. Use the command ip nbar port-map to attach the protocols to an interface.
B.Use the command match protocol rtp to allow identification of real-time audio and video traffic. Use thecommand ip nbar port-map to extend the NBAR functionality for well-known protocols to new port numbers.
C.Use the command match protocol to allow identification of stateful protocols. Use the command ip nbar port-map to attach the protocols to an interface.
D.Configure a traffic class. Configure a traffic policy. Attach the traffic policy to an interface.
E.Configure video streaming. Configure audio streaming. Attach the codec to an interface.