CISCO SEMESTER 4: MODULE 3

How did Cisco alter the HDLC encapsulation to allow a single link to carry multiple protocols?
	split the transmissions into multiple channels each carrying a single protocol
	identified the protocol in the FCS field
	compressed the datagrams differently for each protocol
	added a type field to identify the protocol
A technician has used Telnet to gain remote access to a router that has no connectivity on its serial interface. Which command should be issued to determine if the serial cable is connected properly?
	show controllers
	show processes
	show run
	show status

A two router network is running PPP over the serial interfaces that connect them. The enable password on the Denim router is "gateway". The Denim router also has a locally configured authentication password for the Plaid router which is "fortress". Which command must be executed on the Plaid router to allow Denim to authenticate to the Plaid router using CHAP?
	Plaid(config)# enable secret gateway
	Plaid(config)# enable secret fortress
	Plaid(config)# username Plaid password fortress
	Plaid(config)# username Denim password fortress
	Plaid(config)# hostname Plaid secret password gateway
	Plaid(config)# hostname Plaid secret password fortress

Which authentication protocol can be spoofed to allow playback attacks?
	MD5
	CHAP
	PAP
	NCP

How is the MD5 function valuable in authentication? (Choose two.)
	uses a one-way hash function
	authentication occurs more rapidly
	challenges are unique
	the remote router assumes control of frequency of challenge
	the remote router assumes control of timing of challenge

Which command specifies a link quality over a PPP link?
	ppp link 50
	ppp link quality 60
	ppp percentage 80
	ppp quality 90

Refer to the output of the show interface Serial0/0 command in the graphic. How many NCPs have been established?
	1
	2
	3
	4

Which of the following is an advantage of using time-division multiplexing (TDM) for transmitting data? (Choose two.) It allows a single source to transmit over multiple data channels. Multiple sources can transmit over a single channel. Original data streams must be reconstructed at the destination. TDM relies on Layer 3 protocols to operate.

Which of the following describes the High-Level Data Link Control protocol? (Choose three.)
	HDLC provides flow and error control.
	Standard HDLC supports multiple protocols on a single link.
	HDLC uses sequencing and acknowledgements.
	HDLC is defined as the default encapsulation on Cisco LAN interfaces.
	Cisco implemented a proprietary version of HDLC.

A technician is testing the functionality of a recently installed router. The technician is unable to ping the serial interface of a remote router. The technician executes the show interface serial 0/0 command on the local router and receives the following output: Serial0/0 is up, line protocol is down(disabled) What are possible causes for this command output? (Choose two.)
	interface missing the no shutdown command
	clockrate command missing
	CSU/DSU failed
	interface shutdown due to high error rate
	cable missing

When troubleshooting the Serial 0/0 interface of a router, a technician issues the show controllers command. The following was the output of the command: Interface is Serial0/0, electrical interface is UNKNOWN. What can be concluded about the Serial 0/0 interface? (Choose three.)
	Serial0/0 is down, line protocol is down
	Serial0/0 is down, line protocol is up
	Serial0/0 is up, line protocol is down
	The interface is neither DCE or DTE.
	The interface hardware may be faulty.
	The cabling may be improperly connected.

ISDN BRI service uses two B channels to send data, voice, and video. If the first channel becomes saturated, the second channel can be configured to forward packets. Which command will allow ISDN to load balance across both links? Router(config-if)# ppp quality 2 Router(config-if)# ip variance Router(config-if)# ip maximum-paths 2 Router(config-if)# ppp multilink

Which of the following describe functions of the Point-to-Point protocol with regards to the OSI model? (Choose three.)
	PPP uses Layer 3 of the OSI model to establish and maintain a session between devices.
	PPP operates at all layers of the OSI model.
	PPP uses the data link layer to configure such options as error detection and compression.
	PPP provides a mechanism to multiplex several network layer protocols.
	PPP uses Network Control Protocols (NCP) to test and maintain connectivity between devices.
	PPP can be configured on both synchronous and asynchronous serial interfaces.

PPP uses several protocols for communication. Which of the following are options that the LCP protocol in the PPP architecture can provide? (Choose two.) testing the quality of the link routing packets between devices assigning individual station addresses configuring network layer protocols negotiating authentication options

Several tasks must occur before a link between two routers can pass data using PPP. Which of the following are required to establish and maintain a PPP session between two routers?
	configure each host with a PPP address
	configure authentication between the two routers
	send LCP and NCP frames to negotiate configuration parameters
	send hostname and password information between the two routers

Which of the following is a reason for using such protocols as PAP and CHAP?
	to establish a PPP session
	to provide error checking on a WAN link
	to restrict access to networks connected by serial and ISDN links
	to provide a backup hostname and privilege mode password on the router

Which of the following describes the CHAP protocol? (Choose three.)
	exchanges a random challenge number during the session to verfiy identity
	sends authentication password to verify identity
	prevents transmission of login information in plain text
	disconnects the PPP session if authentication fails
	initiates a two-way handshake

Which command was used to display the partial output shown in the graphic?
	show ppp traffic
	show lcp traffic
	debug ppp negotiation
	debug ppp authentication

What can be concluded from the output shown in the graphic? (Choose three.)
	A two-way handshake is occuring.
	The LCPs were already negotiated.
	The router can begin NCP negotiations.
	The debug ppp negotiation command was executed.
	The debug ppp authentication command was executed.

Which advantage does the multilink option provide when using PPP?
	Data transmission has load balancing possibilities.
	Interfaces can be configured using both HDLC and PPP.
	More than one authentication method can be used.
	More than one compression protocol can be configured.

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CISCO SEMESTER 4: MODULE 2

1	Which statements are correct regarding ATM connections? (Choose two.) uses only PVCs is useful for video transfers has data rates beyond 155 Mbps cells have 32 byte payload and a 5 byte overhead mandates single virtual circuits on a single leased line connection
2	Which of the following describes a packet-switched network using connection-oriented data transfer? (Choose two.) Each packet carries an identifier. Each packet carries full addressing information. Each switch in the route must evaluate the addressing information to determine where to send the packet. Each switch determines where to send the packet by examining tables in memory. The addressing information is used to set switches along the route of data transfer to create a continuous copper circuit.

3	A European company needs a low cost, dialup WAN connection to validate transactions for point-of-sale card readers. Which connection type is commonly used for this situation? ATM X.25 Frame Relay Leased lines
4	Which of the following is commonly used as Data Terminal Equipment? ISDN modem router CSU/DSU

5	A company requires a WAN connection that will carry 64 kbps and allow fast call setup time. The connection does not need to carry video. What is the best choice for this company? ATM ISDN BRI X.25 analog dialup
6	Why is it important to identify the type of traffic that will be carried on the WAN links before choosing a WAN technology? to determine the routing protocol to be used on the WAN link to determine the WAN topology to determine the requirements for latency and jitter to determine the type of signaling protocol to be used on the WAN link

7	On which of the following are most Layer 2 WAN encapsulations based? IP PPP HDLC SLIP HSSI CSU
8	A company only requires a WAN connection to transfer sales data from individual stores to the home office. All transfers will occur after business hours. They estimate they will never need a connection faster than 56 kbps. Which type of connection is best for this company? ATM ISDN analog dialup T1 Leased Line

9	Which of the statements regarding DSL are correct? (Choose three.) DSL provides a consistent bandwidth of 2.154 Mbps. DSL connections provide a fast dialup to establish a WAN connection. DSL connects the local loop to a digital subscriber line access multiplexer. DSL bandwidth varies and can exceed the bandwidth of a T1/E1 leased line. For DSL to function properly, the local loop must be less than 5.5 kilometers (3.5 miles). DSL is a popular choice for enterprises that need to connect home users to the local network due to strong security.
10	Which of the following are disadvantages of circuit-switched networks? (Choose two.) Data is subject to unpredictable delays while it waits for other subscribers to transmit data. The connection capacity is used inefficiently due to irregular traffic bursts. Data delivery is less reliable because only connectionless delivery methods are used. Circuit-switched networks are more expensive for data traffic. Circuit-switched networks are less expensive for 24/7 data traffic.

11	Depending on the company size and geographical layout, there might be many end points on the company WAN. Why is it important to identify all the end points of the WAN before choosing a WAN design? to determine the routing protocol to be used on the WAN link to determine the WAN topology to determine the requirements for latency and jitter to determine the signaling protocol to be used on the WAN link
12	Which of the following is true of WANs? Shared network WAN technologies such as Frame Relay and ATM are more expensive but offer less latency and jitter than dedicated lines. ISDN is suitable for large enterprises. The more network devices that data has to pass through across the WAN, the more latency and less reliability the network will experience. WANs typically incorporate only one technology such as ISDN, Frame Relay, or ATM.

13	A new international company needs to have a design for WAN connectivity. The company will have at least five offices in every state in the United States and Mexico. Some states will have as many as 20 offices. The branch offices will require constant contact with the services of the main office. Which design model is best for WAN connectivity in this situation? a mesh network of all branch WANs a simple star topology connecting all branch LANs to a central router with multiple interfaces a one layer design using Frame Relay links between LANs a three layer hierarchical topology interconnecting branch LANs within an area, the area LANs within a region, and connecting the regions to form the core of the WAN
14	Which statement is true regarding WAN technologies? Most WANS use only one technology throughout the infrastructure such as ISDN, Frame Relay or ATM. Data transfer speeds on the WAN are typically faster than the speeds on a LAN. WANs operate at the lower three layers of the OSI model. WANs are unable to support the transfer of voice or video traffic.

15	A large company already has a T1 leased line but this connection is inadequate at peak business hours. Furthermore, they would like a backup WAN connection in case their leased line temporarily fails. What type of WAN connection is commonly used in this situation? X.25 DSL ISDN cable modem 56 kbps

16	Which term describes the cabling that connects the customer site to the nearest exchange of the WAN service provider? CPE CO local loop DCE DTE
17	Which of the following connections will provide the equivalent of a T1/E1 connection and is intended for large businesses? BRI PRI DLCI PSTN POTS

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