Review Questions

1.	Which of the following statements is true regarding traffic shaping? Traffic shaping eliminates bottlenecks by throttling back traffic volume at the source end. Traffic shaping only works at Layer 3. Traffic shaping cannot be used with Frame Relay or Switched Multimegabit Data Service (SMDS). Traffic shaping only works on Cisco switch technology.
2.	Which of the following might be logged when IP access list logging is enabled? (Choose all that apply.) Source address Source port Destination address Destination port Time Protocol Access list line number Access list number
3.	Which of the following are reasons why access lists are used? (Choose all that apply.) To improve security To reduce routing protocols To save bandwidth To speed convergence
4.	Which of the following will allow IP devices to simply ARP for remote devices and receive the MAC address of a default gateway? IPX Watchdog ARP Proxy ARP Spoofed ARP DDR None of the above
5.	Which of the following would be most useful on a subnet without a DHCP server that required DHCP services? IPX watchdog spoofing Responding to IPX GNS requests Proxy ARP IP helper address None of the above
6.	In which of the following situations would compression be most useful? Insufficient bandwidth Time-sensitive traffic Multiple routing protocols High router CPU utilization
7.	Which of the following are valid types of compression? Header compression Data compression Payload compression Link compression
8.	When using numbered access lists, which range of numbers is used for extended IP access lists? 0–99 100–199 800–899 900–999
9.	To which type of traffic does weighted fair queuing assign the highest priority? SNA IPX High volume Low volume
10.	When should weighted fair queuing be used? To provide priority to interactive traffic To provide priority to file transfers To allow all traffic to be forwarded A and C A and B
11.	Where is the most effective place to implement queuing? High-speed LAN links T1/E1 links only Any WAN link whose capacity is 2Mbps and slower All interfaces
12.	When should priority queuing be used? When traffic has a hierarchical order of importance When delay doesn’t matter When all traffic must be forwarded None of the above
13.	When should custom queuing be used? When traffic has a hierarchical order of importance To overcome the possible problem that is introduced with priority queuing When trying to provide bandwidth sharing for all traffic When delay is not important
14.	Which step is not part of configuring custom queuing? Defining the custom queuing filter Assigning a default queue Configuring the transfer rate per queue Assigning a priority queue list to the interface
15.	Which statement best describes weighted fair queuing? The queues are based on the source and destination of the packets. Bandwidth is shared among all traffic types, giving priority to low-volume traffic. Bandwidth is shared among high-priority traffic only. The queues use FIFO.
16.	Which statement best describes priority queuing? It processes all queues in a round-robin fashion. The queues are based on the destination address of the packet. The queues are based on the traffic type; all queues are processed equally. The queues are based on the traffic type; the highest priority traffic is always processed first.
17.	Which of the following statements is true regarding traffic shaping? Frame Relay can use traffic shaping to adapt dynamically to available bandwidth using the BECN mechanism. IP can use traffic shaping to adapt dynamically to available bandwidth using the BECN mechanism. Traffic shaping does not work with Layer 2 technologies. Traffic shaping processes packets based on the destination address.
18.	In which of the following situations would RSVP be useful? (Choose all that apply.) Insufficient bandwidth Time-sensitive traffic Multiple routing protocols High router CPU utilization
19.	What is the maximum router CPU utilization for enabling compression? 10 percent 100 percent 50 percent 65 percent
20.	Named access lists are available since which IOS revision? 10.2 10.3 11.2 11.3

Answers

1.	A Access lists, along with the Frame Relay BECN mechanism, can be used for traffic shaping to help eliminate network bottlenecks.
2.	A, B, C, D, E, F, H All items are logged either to the console or to a Syslog server for later review except for access list line number.
3.	A, C The primary uses of access lists are traffic control. Security and bandwidth are methods of traffic control.
4.	B Proxy ARP can minimize the need for client reconfiguration of default router addresses.
5.	D IP helper addresses can be configured on the Cisco router and allow for central services network designs.
6.	A Traffic compression is best applied to WAN links where bandwidth is at a premium.
7.	A, C, D Header, payload, and link compression are supported by the Cisco IOS. Header compression only affects the IP header, payload compression only affects the data, and link compression works on both the IP header and data.
8.	B Extended IP access lists are numbered using numbers between 100 and 199.
9.	D Weighted fair queuing assigns the highest priority to low-volume traffic.
10.	A Interactive traffic is time-sensitive and is sensitive to delay.
11.	C Queuing is most effective on WAN links.
12.	A Priority queuing guarantees that higher priority traffic will get sent first.
13.	B Custom queuing allows the network designer to classify traffic at the router interface.
14.	D Defining the filter, assigning the queue, and configuring the transfer rate are all configurations required to configure custom queuing.
15.	B Weighted fair queuing assigns a higher priority to low-volume traffic.
16.	D Traffic type (i.e., high-priority), will be processed through the queue first.
17.	A Frame Relay uses the BECN notification method to dynamically accomplish traffic shaping.
18.	A, B RSVP is used by end stations and routers to guarantee the passage of time-sensitive traffic.
19.	D Cisco recommends that compression be disabled on the router if CPU utilization is greater than 65 percent.
20.	C Named access lists have been available since IOS release 11.2.