4A0-107 Online Practice Questions and Answers

Which of the following are examples of metrics for QoS?

A. Signal degradation, attenuation, line loss

B. Latency, FIFO, WRED

C. Delay, jitter, packet loss

D. SNR, queue depth, latency

E. Attenuation, dispersion, latency

What is the 6-bit binary representation of DSCP value AF21?

A. 010011

B. 100010

C. 010001

D. 001100

E. 010010

Which of the following statements regarding DSCP bits are TRUE? (Choose three)

A. The three most significant (first) bits define 8 forwarding classes.

B. The three least significant (last) bits of the DSCP specify the drop probability.

C. The full 8 bits of the TOS field are used for DSCP.

D. To convert DSCP to IP precedence, the three most significant (first) bits are matched.

E. DSCP provides for eight drop probabilities.

What is the maximum number of forwarding subclasses a forwarding class can have?

A. 3

B. 64

C. 72

D. 16

E. 56

The SAP-ingress policy shown below is applied properly to a Nokia 7750 SR. A traffic stream is received from an IP address of 192.168.2.200 with DSCP and dot1p set to EF and 4, respectively. Which forwarding class and priority level is used for this traffic stream?

A. FC H1, high

B. FCH1, low

C. FCAF, high

D. FCAF, low

Which of the following statements about network QoS policies is FALSE?

A. Classification rules must specify both an FC and a profile for the packets.

B. A network policy is applied at a physical port.

C. Classification is performed with behavior-aggregate statements only.

D. Match criteria can be chosen from dot1p, DSCP, and EXP fields in the packet.

Which of the following statements about the default scheduler in the Nokia 7750 SR is FALSE?

A. The default scheduler spends an equal amount of time servicing each queue that has traffic to be sent out.

B. Queue-type can be configured as best-effort, expedite, or auto-expedite.

C. A queue will be serviced as expedited if its type is configured as expedited, regardless of the forwarding classes mapped to it.

D. A queue configured as auto-expedited will be an expedited queue as long as no Best Effort FC is mapped to it.

An egress port scheduler applied to an Ethernet port has a configured bandwidth of 100 Mbps. All frames transmitted on the port are 80 bytes. What is the aggregate transmit bandwidth of all queues using the port scheduler?

A. 100Mbps * 20/(80 + 20) = 20 Mbps

B. 100Mbps * 80/(80 + 20) = 80 Mbps

C. 100Mbps

D. 100+ 100 * 20/(80 + 20) = 120 Mbps

Which of the following statements about marking packets is TRUE?

A. Packets corresponding to a layer-2 service can be pre-marked on SAP-ingress.

B. Packets corresponding to a layer-2 service can be pre-marked on network-ingress.

C. Packets corresponding to a layer-3 service can be pre-marked on SAP-ingress.

D. Packets corresponding to a layer-3 service can be pre-marked on network-ingress.

Which of the following CANNOT be used as external marking bits?

A. IP Precedence

B. Dot1p

C. Forwarding class

D. EXP