An ISDN circuit from a branch office is remaining
connected to the regional office. A network administrator determines
a user has initiated a continuous ping from a desktop computer to
the regional office. Which configuration change would allow the ISDN
circuit to disconnect during any attempts to ping, while otherwise
functioning properly?
change DDR from legacy to dialer
profiles
remove the dialer list statement
from the configuration
change the dialer list to exclude
ICMP as interesting
disable inverse
ARP
2
Refer to the exhibit. The link between the RTR-1 and
RTR-2 routers is configured as shown in the exhibit. Although the show interfaces command shows the interface status as Serial0 is up, line protocol is up, IP traffic is not
crossing this link. What is the problem?
The usernames are
misconfigured.
The clock rate is configured on the
wrong end of the link.
The IP addresses are not in the
same subnet.
Interface serial 0/0 on RTR-1 must
connect to interface serial 0/1 on RTR-2.
The passwords must be different for
the CHAP authentication.
The clock rate must be
56000.
3
A technician enters the interface serial 0/0.1
multipoint command when configuring a router. What effect will
the multipoint keyword have in this configuration? (Choose
two.)
Split-horizon issues will need to
be resolved for this network if RIP is the routing protocol.
A subinterface will be defined for
each PVC.
All the participating interfaces of
remote routers will be configured in the same subnet.
A single DLCI will be used to
define all the PVCs to the remote routers.
An IP address will need to be
configured on the main interface.
4
A branch office reports excessive connect time charges
for an ISDN circuit used to connect to the regional office. Upon
investigation of this issue, it is discovered that when an ISDN
connection is initiated to the regional office it remains connected
for an excessive amount of time. Which of the following
configuration changes could be made to DDR on the router to reduce
these connect time charges?
use PPP multilink
lower idle timer setting
use CHAP authentication
change DDR from legacy to dialer
profiles
5
Which router command would be used to associate a
Layer 2 address with the corresponding Layer 3 address in the
internetwork in the diagram?
What does the output of the show frame-relay
map command shown below represent? (Choose two.)
Serial 0
(up): ip 172.30.151.4 dlci 122, dynamic, broadcast, status defined,
active
172.30.151.4 represents the
IP address of the remote router.
172.30.151.4 represents the
IP address of the local serial interface.
DLCI 122 represents the
interface of the remote router.
broadcast indicates that a
dynamic routing protocol such as RIP v1 can send packets across this
PVC.
dynamic indicates that a
dynamic routing protocol is enabled for this connection.
active indicates that the
ARP process is working.
7
Refer to the exhibit. The network administrator of the
Denver router has determined that the DHCP clients on the network
are not working properly. The clients are receiving IP configuration
information from a DHCP server configured on the router but cannot
access the Internet. From the output in the exhibit, what is the
most likely problem?
The DHCP server service is not
enabled.
The DHCP pool is not bound to the
interface.
The inside interface for DCHP is
not defined.
The pool does not have a default
router defined for the clients.
All the host addresses have been
excluded from the DHCP pool.
8
What are two ways to resolve split-horizon issues in a
Frame Relay network? (Choose two.)
create a full-mesh topology
disable Inverse ARP
use point-to-point
subinterfaces
use multipoint subinterfaces
remove the broadcast keyword
from the frame-relay map command
9
What is the purpose of the command marked with an
arrow shown in the partial configuration output of a Cisco 806
broadband router?
defines which addresses are allowed
out of the router
defines which addresses are allowed
into the router
defines which addresses can be
translated
defines which addresses are
assigned to a NAT pool
10
Which scenarios present possible reasons for using the frame-relay map command when configuring a Frame Relay
connection? (Choose two.)
when dynamic mapping of DLCIs to IP
addresses is not supported by the remote router
when the local router is using IOS
Release 11.1 or earlier
when the remote router is a
non-Cisco router
when globally significant rather
than locally significant DLCIs are being used
when broadcast traffic and
multicast traffic over the PVC must be
controlled
11
While testing a new network design in the lab, a
network administrator is configuring a serial link that connects two
routers back-to-back. In order to finish the configuration, the
administrator needs to identify which router is connected to the DCE
end of the cable. What command can be issued to provide this
information?
router# show status serial
0/0
router# show controllers serial
0/0
router# show protocols serial
0/0
router# show version
router# show interfaces serial
0/0
12
Which statements are correct about the point in the
network where the responsibility of the service provider ends?
(Choose three.)
The International point is on the
customer side of the network terminating unit(NTU).
The United States point is at the
interface of the customer-provided equipment and the local
loop.
The responsibility for this point
is controlled by IANA.
The point is called the demarcation
point.
The point is typically located at
the service provider's central office.
The point is located between the
customer's local area networks.
13
A system administrator is unable to ping the Serial0/0
interface of RouterB from RouterA. During the troubleshooting
process, the following facts are established:
- IP addressing and
subnet masks are correct.
- RouterA is a Cisco router and RouterB
is a router from another vendor.
- RouterA is configured with the
default encapsulation.
- The serial interfaces on both routers
are up.
- The protocol is down on the serial interfaces of both
routers.
What should the administrator do to solve the
problem?
Add a clock rate on RouterA.
Enable the serial interface on
RouterB.
Change the encapsulation on both
routers to PPP.
Connect the serial cable to the
correct interface on RouterB.
Use the correct serial cable to
attach the CSU/DSU to RouterB.
14
When a Frame Relay switch detects an excessive buildup
of frames in its queue, which of the following may occur? (Choose
two.)
Frames with the DE bit set are
dropped from the switch queue.
Frames with the FECN and BECN bits
set are dropped from the switch queue.
Frames in excess of the CIR are not
accepted by the switch.
The switch sets the FECN bit on all
frames it places on the congested link and sets the BECN bit on all
frames it receives on the congested link.
The switch sets the FECN bit on all
frames it receives on the congested link and sets the BECN bit on
all frames it places on the congested
link.
15
Refer to the exhibit. A network administrator is
checking the status of router RTR_2. What is the most likely reason
for the current status of the serial link to RTR_1?
A cable has become
disconnected.
The circuit is experiencing
excessive RFI.
Authentication is not properly
configured on the routers.
The routers are configured for
different WAN encapsulations.
The clock rate is not properly
configured on one of the routers.
16
What are two of the steps required to configure a
router to connect over ISDN BRI? (Choose two.)
Configure the interface with a
DLCI.
Configure the SPIDs, if required by
the ISDN switch.
Specify the the LMI type to be
compatible with the CO switch.
Set the interface encapsulation to
the Cisco or IETF frame type.
Configure a subinterface for each B
channel.
Set the switch type to work with
the ISDN switch at the CO.
17
What value in the address field of a Frame Relay
header identifies the destination of the frame?
CIR
DE
DLCI
ISDN
FRAD
PVC
18
Which of the following describes the roles of devices
in a WAN? (Choose three.)
A CSU/DSU terminates a digital
local loop.
A modem terminates a digital local
loop.
A CSU/DSU terminates an analog
local loop.
A modem terminates an analog local
loop.
A router is commonly considered a
DTE device.
A router is commonly considered a
DCE device.
19
Refer to the exhibit. Two routers are connected
through a Frame Relay point-to-point PVC. The ILM-5 router is from a
vendor other than Cisco. Which interface command is required to
configure the link between the Cisco ILM-3 router and router
ILM-5?
ILM-3(config-if)# encapsulation
frame-relay cisco
ILM-3(config-if)# frame-relay
pvc multipoint
ILM-3(config-if)# encapsulation
frame-relay ietf
ILM-3(config-if)# frame-relay
lmi-type ansi
ILM-3(config-if)# frame-relay
pvc point-to-point
20
The output of the show interfaces serial 0/0 command for a frame-relay connection indicates that the serial line
is up but the line protocol is down. What are possible causes for
this? (Choose two.)
There is an LMI-type mismatch
between the Frame Relay switch and the router.
There is no clock present on the
serial interface.
The interface is shut down.
RARP is not functioning on the
router.
The cable is
disconnected.
21
After configuring a dialup ISDN circuit, a network
associate begins testing the dialup connection. When attempting to
ping a host on the remote network, the local router does not attempt
to dial the remote access server. Which of the following are
possible errors in this configuration? (Choose three.)
PPP authentication is not properly
configured.
No dialer map is configured.
The ISDN circuit connected to the
remote access server is busy.
No interesting traffic is
defined.
No route is determined to the
remote network.
A wrong number is configured in the
dial string.
22
When configuring a Frame Relay network with
subinterfaces, which commands are configured on the subinterface?
(Choose three.)
frame-relay
interface-dlci
encapsulation frame-relay
ietf
ip address
frame-relay map
switch
type
23
Below is a list of DDR steps. Which of the following
identifies the proper order of DDR?
1 - dial number is looked
up
2 - interesting traffic triggers DDR
3 - route to
destination is determined
4 - call is made
1,2,3,4
1,3,2,4
2,3,1,4
2,1,3,4
3,2,1,4
3,1,2,4
24
A network administrator issued the command show
frame-relay pvc. The response from the router shows the status
of a PVC as deleted. What is the reason for this
output?
The DLCI is using the wrong LMI
type.
The DLCI is usable but has little
activity.
The DLCI is programmed in the
switch but the circuit is not usable.
The DLCI was formerly programmed in
the switch but is no longer there.
25
The serial PPP link between the Left and Right routers
is configured as shown in the diagram. Which configuration issue
explains why the link is unable to establish a PPP
session?
The IP addresses must be on
different subnets.
The usernames are
misconfigured.
The passwords must be different for
the CHAP authentication.
The clock rate must be 56000.
The clock rate is configured on the
wrong end of the link.
Interface serial 0/0 on Left must
connect to interface serial 0/1 on
Right.
26
Which protocol should be chosen to support WAN
connectivity in a multi-vendor system and provide strong security
through authentication?
NAT with DHCP
Frame Relay
HDLC with encryption
HDLC with CHAP
PPP with PAP
PPP with
CHAP
27
Refer to the exhibit. Which statements describe why
the workstation with the IP address 192.168.89.99 cannot access the
Internet? (Choose two.)
The NAT outside interface is not
configured properly.
The NAT inside interface is not
configured properly.
The access control list does not
include the IP address 192.168.1.99/28 to access the Internet.
The NAT pool is not properly
configured to use routable outside addresses.
The NAT pool is not properly
configured to use the access control list for
NAT.
28
After the ISDN BRI interface is configured, which
command can be used to verify that the router is communicating
correctly with the ISDN switch?
show dialer
show isdn status
show interfaces
bri0/0:1
show interfaces
serial0/0.1
29
How are the settings for ISDN switch type and SPIDs
determined for a BRI interface configuration?
assigned by the network
administrator
randomly, so long as they are not
duplicated on the network
by trial and error
dynamically via Inverse ARP
assigned by IANA
assigned by the service
provider
30
A network administrator is having difficulty in
establishing a serial link between a Cisco router and a router from
another vendor. Both routers are configured for HDLC encapsulation.
Which statements are true regarding this configuration? (Choose
two.)
The Cisco HDLC frame uses a
proprietary "Type" field that may not be compatible with equipment
of other vendors.
HDLC requires a clock rate to be
configured on the routers at both ends of the serial link.
PPP encapsulation is recommended
for serial links between equipment from multiple vendors.
Usernames must be configured at
both ends of the HDLC serial link.
The HDLC vendor type must be
enabled on the Cisco router.
There is a mismatch in the HDLC
authentication password
configurations.
31
A system administrator is troubleshooting a
connectivity issue between two routers in a new installation. The
administrator enters the debug ppp authentication command on
the WHSE router. The graphic shows a part of the output received.
From this output, what is the most likely cause of this connectivity
issue?
There is not a route to the remote
router.
The ISDN circuit on the remote
router has failed.
The username/password was not
properly configured on the WHSE router.
The remote router has a different
authentication protocol configured.
32
A system administrator needs to configure the regional
office with ISDN for DDR connections to three remote sites. Each
remote site requires different IP subnets, different encapsulations,
and different authentication methods. The sites will not be
connected at the same time. The company would like to accomplish
this in the most cost effective manner. What method can the system
administrator use to accomplish this task using the fewest B
channels?
Install and configure a PRI.
Install and configure a BRI
interface with separate SPIDs for each remote site.
Install and configure a BRI with
multiple switch types in global configuration.
Install and configure a BRI using
dialer profiles.
Install and configure a separate
BRI for each remote site.
33
Which IP addresses are defined by RFC 1918 as private
addresses? (Choose three.)
172.55.16.0.16
172.17.0.0/16
224.200.175.0/24
192.168.168.0/22
10.88.179.0/29
17.250.0.0/16
34
Which of the following statements are correct
regarding PAT? (Choose two.)
PAT is the best method to provide
consistent global addresses for network servers.
PAT can only be configured to use
one IP address, which is usually the IP address of the serial
interface of the router.
PAT uses unique source port numbers
on the inside local IP address to distinguish between
translations.
PAT uses unique source port numbers
on the inside global IP address to distinguish between
translations.
When PAT is configured to use a
pool of IP addresses and exhausts the ports of the first IP address,
the router will move to the next available IP
address.
35
Which circuit-switched WAN technology is often used to
provide a backup for a leased line and additional capacity during
peak usage times?
X.25
DSL
ISDN
cable
modem
36
Which of the following is the order for the three
phases of establishing a PPP serial link with
authentication?
A system administrator must provide Internet
connectivity for 25 hosts at an insurance agency. The ISP has
assigned two public IP addresses to this company. What can the
administrator do to provide Internet access to all 25 users at the
same time?
Configure the router with dynamic
NAT with PAT.
Configure the router with dynamic
NAT for 25 users.
Configure the router with DHCP and
static NAT.
Configure the router with static
NAT for all 25 users.
This cannot be done with only two
public addresses.
39
A network administrator must provide WAN connectivity
between the Central office and three remote sites: East Branch, West
Branch, and Remote. The East Branch and West Branch offices receive
sales orders and transmit shipping confirmations to the Central
office consistently throughout the day. The Remote office is staffed
by one salesperson who travels through the northwestern territory.
The salesperson occasionally needs to connect to the Central office
for e-mail access. How should the network administrator connect
these sites to the Central office? (Choose two.)
Connect the East Branch and West
Branch remote offices with ISDN connections.
Connect the East Branch and West
Branch offices with Frame Relay connections.
Connect the East Branch and West
Branch offices with POTS dial-up connections.
Connect the Remote office with a
Frame Relay connection.
Connect the Remote office with an
ISDN connection.
Connect the Remote office with a
POTS dial-up connection.
40
Which of the following ISDN protocols is responsible
for call setup and call teardown?
