24.Congestion Control and Quality of Service

_______ is a flow characteristic that applications can tolerate in different degrees.

• Reliability
• Delay
• Jitter
• Bandwidth

The _______ defines the maximum data rate of the traffic.

• peak data rate
• maximum burst size
• effective bandwidth
• none of the above

In Frame Relay, the _____________ defines an average rate in bits per second.

• access rate
• committed burst size
• committed information rate
• excess burst size

In ________ congestion control, policies are applied to prevent congestion before it happens.

• open-loop
• closed-loop
• either (a) or (b)
• neither (a) nor (b)

In ________ we try to avoid traffic congestion.

• congestion control
• quality of service
• either (a) or (b)
• both (a) and (b)

_________ is a characteristic that a flow needs. Lack of it means losing a packet or acknowledgment, which entails retransmission.

• Reliability
• Delay
• Jitter
• Bandwidth

In a network, after the load reaches the capacity, throughput _______.

• increases sharply
• increases proportionally with the load
• declines sharply
• declines proportionally with the load

In _________ queuing, the packets are assigned to different classes and admitted to different queues. The queues, however, are weighted based on the priority of the queues; higher priority means a higher weight. The system processes packets in each queue in a round-robin fashion with the number of packets selected from each queue based on the corresponding weight.

• FIFO
• priority
• weighted fair
• none of the above

In ATM, the _________ class is a best-effort delivery service that does not guarantee anything.

• CBR
• VBR
• ABR
• UBR

The________ normally refers to the maximum length of time the traffic is generated at the peak rate.

• peak data rate
• maximum burst size
• effective bandwidth
• none of the above