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
2
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
3
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?
Refer to the output of the show interface
Serial0/0 command in the graphic. How many NCPs have been
established?
1
2
3
4
5
Which command specifies a link quality over a PPP
link?
ppp link 50
ppp link quality 60
ppp percentage 80
ppp quality
90
6
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.
7
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
8
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
9
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.
10
Which authentication protocol can be spoofed to allow
playback attacks?
MD5
CHAP
PAP
NCP
11
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
12
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
13
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
14
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.
15
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.
16
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
17
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
18
What are three features of the CHAP protocol? (Choose
three.)
exchanges a random challenge number
during the session to verify 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
19
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.
20
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.
