Testking_640-802_V13

Answer: D Explanation:

HDLC and PPP configuration is straightforward. You just need to be sure to configure the same WAN data-link protocol on each end of the serial link. Otherwise, the routers will misinterpret the incoming frames, because each WAN data-link protocol uses a different frame format. The routers must match at each end of the private leased line link. Reference: CCNA Self-Study CCNA ICND exam certification Guide (Cisco Press, ISBN 1-58720-083-X) Page 310.

Section 5: Describe VPN technology (including: importance, benefits, role, impact, components) (0 questions)

Section 6: Configure and verify a PPP connection between Cisco routers (10 questions)

QUESTION NO: 1

Two TestKing buildings are connected together as shown below:

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The TestKing network administrator is in a campus building distant from Building B. The WANRouter is hosting a newly installed WAN link on interface S0/0. The new link is not functioning and the administrator needs to determine if the correct cable has been attached to the S0/0 interface. How can the administrator accurately verify the correct cable type on S0/0 in the most efficient manner?

A.Physically examine the cable between TestKing2 S0/0 and the DCE

B.Telnet to TestKing2 and execute the command show interface S0/0

C.Telnet to TestKing2 and execute the command show controller S0/0

D.Telnet to TestKing2 and execute the command show processes S0/0

E.None of the above

Answer: C

QUESTION NO: 2

Two TestKing routers are connected via a PPP connection. Which of the following are key characteristics of this PPP connection? (Choose three)

A.PPP can be used over analog circuits

B.PPP encapsulates several routed protocols

C.PPP maps Layer 2 to Layer 3 address

D.PPP provides error correction

E.PPP supports IP only

F.PPP provides encryption services

Answer: A, B, D

QUESTION NO: 3

In a point to point connection between two TestKing offices, which PPP subprotocol negotiates authentication options?

A.NCP

B.ISDN

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C.SLIP

D.LCP

E.DLCI

Answer: D Explanation:

LCP: A method of establishing, configuring, maintaining, and terminating the point-to-point connection.

Link-establishment phase LCP packets are sent by each PPP device to configure and test the link. These packets contain a field called the Configuration Option that allows each device to see the size of the data, compression, and authentication. If no Configuration Option field is present, then the default configurations are used.

QUESTION NO: 4

Routers TK1 and TK2 are connected via a private line using PPP. On this link, which of the following options lists the steps in PPP session establishment in the correct order?

A.network layer protocol phase, optional authentication phase, link establishment phase

B.link establishment phase, network layer protocol phase, optional authentication phase

C.optional authentication phase, network layer protocol phase, link establishment phase

D.link establishment phase, optional authentication phase, network layer protocol phase

E.network layer protocol phase, link establishment phase, optional authentication phase

F.optional authentication phase, link establishment phase, network layer protocol phase

G.None of the above

Answer: D Explanation:

According to the related RFC on CHAP: In order to establish communications over a point-to-point link, each end of the PPP link must first send LCP packets to configure the data link during Link Establishment phase. After the link has been established, PPP provides for an optional Authentication phase before proceeding to the Network-Layer Protocol phase.

Reference: http://www.ietf.org/rfc/rfc1994.txt

QUESTION NO: 5

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You are about to configure PPP n the interface of a Cisco router. Which authentication methods could you use? (Select two answer choices)

A.SSL

B.SLIP

C.PAP

D.LAPB

E.CHAP

F.VNP

Answer: C, E

Explanation:

Password Authentication Protocol (PAP) and Challenge Handshake Authentication Protocol (CHAP) authenticate the endpoints on either end of a point-to-point serial link. Chap is the preferred method today because the identifying codes flowing over the link are created using a MD5 one-way hash, which is more secure that the clear-text passwords sent by PAP.

Reference:

CCNA Self-Study CCNA ICND exam certification Guide (Cisco Press, ISBN 1-58720-083-X) Page 314

QUESTION NO: 6

In a lab, two routers are connected directly together using serial interfaces in a back-to-back configuration. No external DCE devices are being used. What additional command is needed to bring this link up?

A.serial up

B.clockrate

C.clock rate

D.dce rate

E.dte rate

F.None of the above

Answer: C Explanation:

The clock rate command (two words), is used to provide clocking on a line where no DCE device is located. Clocking must be provided by one end of this link. Normally in a point to point HDLC or PPP connection the clock rate is supplied by the network provider.

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Incorrect Answers:

A.This is an invalid command

B.This command will not work. The clock rate command must use two words. D, E: These are invalid commands.

QUESTION NO: 7

An ISDN link can be encapsulated using either PPP or HDLC. What are the advantages of using PPP? (Select two answer choices)

A.PPP is easier to configure and maintain than HDLC.

B.PPP is consistently implemented among different equipment vendors.

C.PPP will run faster and more efficiently than HDLC on circuit-switched ISDN links.

D.PPP authentication will prevent unauthorized callers from establishing an ISDN circuit.

E.PPP can be routed across public facilities, while HDLC is not routable in

circuit-switched networks.

F. PPP supports asynchronous communication.

Answer: B, D

Explanation:

PPP has numerous advantages over HDLC. Unlike HDLC which is Cisco proprietary, PPP was designed for multi-protocol interoperability. Secondly, PPP supports authentication, using either PAP or CHAP. Finally, PPP supports error correction and the use of bonded multilink circuits.

Incorrect Answers:

A. The default encapsulation is HDLC. PPP must be explicitly configured and there are many more options available with it, so it is more complicated than HDLC.

C. HDLC is slightly more efficient than PPP.

E.Neither PPP nor HDLC work in public circuit switched environments.

F.Although this is true, it would not be considered an advantage on an ISDN link, as ISDN signaling is not asynchronous.

Reference: CCNA Self-Study CCNA ICND exam certification Guide (Cisco Press, ISBN 1-58720-083-X) Page 308-310

QUESTION NO: 8

Which of the following correctly describe characteristics of PPP? (Select all valid answer choices)

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A.Encapsulates several different types of routing protocols.

B.Supports only IP.

C.Can be used over analog circuits.

D.Is proprietary to Cisco

E.Supports error correction.

Answer: A, C

Explanation:

Characteristics of PPP:

*PPP can be used on either type of line (dial or switched lines), because data-link protocols are designed for point-to-point environment.

*PPP uses one LCP per link and one Control Protocol for each Layer 3 protocol defined on the link. If a router is configured for IPX, Apple Talk, and IP on a PPP serial link, the router configured for PPP encapsulation automatically tries to bring up the appropriate control protocols for each layer 3 protocol.

Incorrect Answers:

B. PPP can be used to support any higher layer protocol, including IP, IPX, Appletalk, etc.

D. PPP is an industry standard used in point to point data networks. The Cisco proprietary method that is similar to PPP is HDLC.

Reference:

CCNA Self-Study CCNA ICND exam certification Guide (Cisco Press, ISBN 1-58720-083-X) Page 309

QUESTION NO: 9

You are preparing to create a point to point WAN by connecting a Cisco router with a Juniper router by way of their serial links. Which one of the following commands would you use?

A.TK1(config-if)# encapsulation hdlc ansi

B.TK1(config-if)# encapsulation ppp

C.TK1(config-if)# encapsulation LAPD

D.TK1(config-if)# encapsulation frame-relay ietf

E.TK1(config)#encapsulation ppp

Answer: B

Explanation:

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PPP is the best encapsulation type to use, when connecting routers of different manufacturers, because PPP is non proprietary (unlike HDLC). PPP is an industry standard layer 2 encapsulation type that is supported by every router manufacturer.

Incorrect Answers:

A. HDLC is a cisco proprietary method of encapsulation for connecting a point to point connection. Although HDLC has become so popular that many other router vendors also support it, HDLC ANSI is not an option that can be used.

C.LAPD is used as an out of band signaling protocol on connections such as ISDN. It is not a choice that can be made in this case.

D.This would be the correct choice if the connection was a frame relay connection, instead of a leased line connection. The ietf keyword is needed for connecting frame links to routers that are non-cisco.

E.This command needs to be placed in interface configuration mode, not in global configuration mode.

QUESTION NO: 10

Router TestKing1 exhibit:

Router TestKing2 exhibit:

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Referring to the command outputs from the TestKing routers shown above , which of the following reasons would you attribute the connectivity problem between the two routers?

A.The authentication needs to be changed to PAP for both routers.

B.The serial IP addresses of routers are not on the same subnet.

C.The username/password combination is incorrectly configured.

D.The router names are incorrectly configured.

E.None of the above

Answer: C Explanation:

When configuring for CHAP authentication, you must enters the other router's user name and password. In this case on router TestKing2 has entered incorrect router TestKing1's password, witch is "cisco1" (it must be "cisco"). As a result CHAP authentication will fail, therefore the connection establishment between the routers will be refused.

Reference:

CCNA Self-Study CCNA ICND Exam Certification Guide Chapter 9 page 315ISBN: 1-58720-083-x

Incorrect Answers:

A.Either PAP or CHAP can be used for these routers.

B.Although this appears to be true at first glance, the subnet mask is 255.255.248.0, and the IP addresses on each side of the link are indeed on the same subnet.

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D. The hostnames are configured correctly, but the passwords do not match.

TOPIC 9, TESTKING NETWORK, SCENARIO

Refer to the diagam of the TestKing network below for the following 5 questions:

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The TestKing network shown above depicts how a satellite office is connected to the Internet via a single connection. The following 5 questions will all refer to this diagram.

TOPIC 9, TESTKING NETWORK (5 questions)

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