A. It supports admission control that allows a network to reject or downgrade new RSVP sessions if one of the interfaces in the path has reached the limit （that is， all reservable bandwidth is booked）.
B. RSVP signals QoS requests per individual flow. In the request the authorized user （authorization object） and needed traffic policy （policy object） are sent. The network can then provide best-effort delivery to these individual flows.
C. RSVP streamlines communication by making it unnecessary to inform network devices of flow parameters （IP addresses and port numbers）.
D. Because of the stateful RSVP architecture， continuous signaling does not have to occur.
E. The flow-based approach is scalable to large implementations， such as the public Internet， because RSVP tracks each individual flow.

A. 8
B. 5
C. 4
D. 3

A. Resource Reservation Protocol （RSVP）
B. first-in， first-out （FIFO）
C. best-effort
D. CBWFQ
E. IntServ
F. DiffServ

A. Packets can arrive out of order.
B. Packets must take the same path to the destination.
C. Once packets are received at the destination router， the router performs sampling to ensure the quality of the voice traffic.
D. Packets can experience varying delays across the network.
E. Packets containing voice samples are sequentially numbered by default， allowing for reordering upon arrival at the terminal router along the path.

A. Compress payload.
B. Use header compression.
C. Increase link capacity.
D. Use random early detection.
E. Guarantee bandwidth to fragile flows.
F. Implement network-based application recognition.

A. connects traditional telephony devices to voice over IP infrastructure
B. converts analog signals to digital format
C. performs voice compression
D. performs call processing
E. performs dial plan administration
F. performs signaling and device control

A. The rate of traffic is measured and compared to a configured policy.
B. Classification is used to differentiate traffic.
C. Traffic is marked and sent out according to priority.
D. Both can be applied to inbound and outbound traffic.
E. Both buffer traffic to ensure a predetermined traffic rate.
F. Both drop traffic that is above a predetermined traffic rate.

A. In a Frame Relay network， delay sensitive traffic is tagged with the discard eligible （DE） bit.
B. In an MPLS network， the three most significant bits of the DSCP or the IP precedence of the IP packet are copied into the MPLS EXP field.
C. In an MPLS network， the MPLS EXP bits are used to identify up to 16 CoS values.
D. The differentiated services code point （DSCP） field consists of the first three bits of the IP precedence field in the header of an IP packet.
E. The 802.1Q standard uses a three bit field referred to as the user priority bits （PRI） to mark packets as belonging to a specific CoS.

A. packetization
B. quantization
C. decoding
D. sampling

A. to eliminate the need for VoIP gateways
B. to scale a VoIP installation with multiple gateways
C. to provide call admission control and limit the number of simultaneous calls on the network 
D. to meet the requirement to control H·323 gateways on a LAN
E. to accept call requests and reduce the load on the gateway