Why are Network Control Protocols used in PPP?
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to establish and terminate data links
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to provide authentication capabilities to PPP
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to manage network congestion and to allow quality testing of the link
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to allow multiple Layer 3 protocols to operate over the same physical link
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What is the data transmission rate for the DS0 standard?
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44 kb/s
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64 kb/s
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1.544 Mb/s
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44.736 Mb/s
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In which two layers of the OSI model are key differences found between a LAN and a WAN. (Choose two.)
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Layer 1
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Layer 2
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Layer 3
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Layer 4
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Layer 6
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Layer 7
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Which statement is true about the Cisco implementation of the HDLC protocol?
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It supports authentication.
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It has a universally compatible frame format.
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It is the default encapsulation for serial interfaces on Cisco routers.
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It does not support multiple protocols across a single link.
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Refer to the exhibit. A network administrator has a connectivity problem between the serial interfaces of Merida and Vargas. What is the cause of the problem? | |
Authentication is required on the serial link.
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The encapsulation is misconfigured.
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The IP addresses are on different subnets.
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The serial interface on Vargas is shutdown.
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The loopback interfaces on both routers are not configured.
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Refer to the exhibit. What statement is true about the exhibited output? | |
LCP is in the process of negotiating a link.
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LCP and NCP are waiting for CHAP authentication to complete.
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LCP negotiation has completed successfully, but NCP negotiation is in progress.
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LCP and NCP negotiation is complete, and the data link service is available to carry packets.
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Which three statements are true regarding LCP? (Choose three.)
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It is responsible for negotiating link establishment.
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It negotiates options for Layer 3 protocols running over PPP.
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It uses MD5 encryption while negotiating link-establishment parameters.
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It terminates the link upon user request or the expiration of an inactivity timer.
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It can test the link to determine if link quality is sufficient to bring up the link.
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It monitors the link for congestion and dynamically adjusts the acceptable window size.
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Why are Frame Relay paths referred to as virtual?
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Frame Relay PVCs are created and discarded on demand.
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The connections between PVC endpoints act like dialup circuits.
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There are no dedicated circuits to and from the Frame Relay carrier.
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The physical circuits inside the Frame Relay cloud do not contain exclusive links for a specific Frame Relay connection.
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What best describes the use of a data-link connection identifier (DLCI)?
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an address identifying a virtual circuit
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a logical address identifying the DCE device
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an address identifying a Layer 3 service across a Frame Relay network
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a logical address identifying the physical interface between a router and a Frame Relay switch
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What
two services allow the router to dynamically map data link layer
addresses to network layer addresses in a Frame Relay network? (Choose
two.)
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ARP
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ICMP
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Proxy ARP
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Inverse ARP
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LMI status messages
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Which three statements describe functions of the Point-to-Point Protocol with regards to the OSI model? (Choose three.)
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operates at all layers of the OSI model
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provides a mechanism to multiplex several network layer protocols
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can be configured on both synchronous and asynchronous serial interfaces
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uses Layer 3 of the OSI model to establish and maintain a session between devices
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uses the data link layer to configure such options as error detection and compression
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uses network control protocols to test and maintain connectivity between devices
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At what physical location does the responsibility for a WAN connection change from the user to the service provider?
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demilitarized zone (DMZ)
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demarcation point
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local loop
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cloud
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What does a Frame Relay switch use to inform the sender that there is congestion?
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FECN
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BECN
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DE
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FCS
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Refer to the exhibit. What statement is true about the debug output? | |
R2 is using PAP instead of CHAP.
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The routers have different CHAP passwords configured.
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The administrator performed a shutdown on the R2 PPP interface during negotiation.
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The Layer 3 protocol negotiation caused the connection failure.
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Which two statements describe the function of time-division multiplexing? (Choose two.)
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Multiple data streams share one common channel.
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Conversations that require extra bandwidth receive any unused time slices.
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Time slots are utilized on a first-come, first-served basis.
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Time slots go unused if a sender has nothing to transmit.
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Priority can be dedicated to one data source.
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When
customers use credit cards to make purchases at a small business, a
modem is heard dialing a telephone number to transfer the transaction
data to the central office. What type of WAN serial connection is in
use?
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leased line
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point-to-point
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circuit switched
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packet switched
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Which best describes data communications equipment (DCE)?
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serves as data source and/or destination
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responsible for negotiating windowing and acknowledgements
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physical devices such as protocol translators and multiplexers
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equipment that forwards data and is responsible for the clocking signal
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Permanent virtual circuits and switched virtual circuits are both part of which option for WAN connectivity?
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leased line
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cell switching
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packet switching
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circuit switching
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Which field of a frame uses error detection mechanisms to verify that the frame is not damaged in transit?
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FCS
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MTU
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flag
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control
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protocol
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What occurs in the encapsulation process as a data packet moves from a LAN across a WAN?
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The Layer 2 encapsulation changes to a format that is appropriate for the WAN technology.
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The Layer 3 encapsulation changes to a format that is appropriate for the WAN technology.
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Both Layer 2 and Layer 3 encapsulation change to a technology that is appropriate for the WAN.
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Both Layer 2 and Layer 3 encapsulation remain constant as the data packet travels throughout the network.
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Refer to the exhibit. The network administrator is configuring R1 to connect to R2, which is a non-Cisco router. Which encapsulation method will need to be configured for communication to occur? | |
HDLC
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HSSI
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ISDN
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IPCP
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PPP
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A
company is implementing dialup services for remote workers to connect
to the local network. The company uses multiple Layer 3 protocols and
requires authentication for security. Which protocol should be used
for this remote access?
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LMI
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PPP
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HDLC
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Frame Relay
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Which two options can LCP negotiate? (Choose two.)
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compression
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authentication
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dynamic flow control
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network layer address for IP
| |
connection-oriented or connectionless communication methods
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What statement best describes cell switching?
| |
It uses a dedicated path between endpoints.
| |
It creates a permanent physical link between two points.
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It uses DLCIs to identify virtual circuits.
| |
It creates fixed-length packets that traverse virtual circuits.
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CCNA3 CAPTER 7