Cisco 642-642 Exam - TopITexams.com
Free 642-642 Sample Questions:
1.What is the purpose of the qos pre-classify command?
A. to enable the IOS to copy the ToS field from the original IP header to the outer tunnel IP header
B. to enable the IOS to copy the ToS field from the outer tunnel IP header back into the original IP header
C. to enable the IOS to classify the packet based on the original IP header instead of the tunnel IP header
D. to enable the IOS to classify the packet based on the outer tunnel IP header instead of the original IP header
E. to enable class-based marking on tunnel interface
F. to enable class-based marking on IPSec crypto maps
2.What are two benefits of WFQ? (Choose two.)
A. WFQ is very easy to configure, and no manual traffic classification is necessary.
B. WFQ can provide fixed-bandwidth and fixed-delay guarantees. C. WFQ can provide fixed-bandwidth guarantees.
D. WFQ can provide fixed-delay guarantees.
E. WFQ prevents the large-volume flows with large packet size from starving out the low-volume flows with small packet size.
F. Based on DSCP, WFQ allows weighted, random dropping of packets when the WFQ system is full.
Answer: A, E
3.What are three reasons link efficiency mechanisms are deployed on WAN links? (Choose three.)
A. decrease delay
B. decrease jitter
C. increase link speed
D. increase throughput
E. decrease propagation delay
Answer: A, B, D
4.Which mechanism is used for the prioritizing, protection, and isolation of traffic based on marking?
A. classification and marking
B. congestion management
C. congestion avoidance
5.Which technology is required when configuring FRF.12 on a Cisco device?
D. MLP with interleaving
6.What are three methods of reducing delay for critical applications in a converged network? (Choose three.)
A. Apply payload compression.
B. Increase link capacities.
C. Apply header compression.
D. Increase LFI fragment size.
E. Reduce inter-packet gaps.
F. Increase all queue depths.
Answer: A, B, C
7.At the network layer, IP packets are typically classified based on which three items? (Choose three.)
A. packet length
B. VLAN Identifier
C. flow control bits
D. source and destination IP addresses
E. content of the ToS byte
Answer: A, D, E