100-105 | how many questions of 100-105 practice test?

Question No: 3

Some routers have been configured with default routes. What are some of the advantages of using default routes? (Choose two)

A. They establish routes that will never go down.

B. They keep routing tables small.

C. They require a great deal of CPU power.

D. They allow connectivity to remote networks that are not in the routing table

E. They direct traffic from the internet into corporate networks.

Answer: B,D

Explanation:

Cisco administration 101: What you need to know about default routes Reference:

http://www.techrepublic.com/article/cisco-administration-101-what-you-need-to-know- about-default-routes/

Question No: 4

The following commands are entered on the router:

Burbank(config)# enable secret fortress Burbank(config)# line con 0 Burbank(config-line)# login

Burbank(config-line)# password n0way1n Burbank(config-line)# exit

Burbank(config)# service password-encryption What is the purpose of the last command entered?

A. to require the user to enter an encrypted password during the login process

B. to prevent the vty, console, and enable passwords from being displayed in plain text in the configuration files

C. to encrypt the enable secret password

D. to provide login encryption services between hosts attached to the router

Answer: B

Explanation:

Certain types of passwords, such as Line passwords, by default appear in clear text in the configuration file. You can use the service password-encryption command to make them more secure. Once this command is entered, each password configured is automatically encrypted and thus rendered illegible inside the configuration file (much as the Enable/Enable Secret passwords are). Securing Line passwords is doubly important in networks on which TFTP servers are used, because TFTP backup entails routinely moving config files across networksu2014and config files, of course, contain Line passwords.

Question No: 5

Refer to the exhibit.

If CDP is enabled on all devices and interfaces, which devices will appear in the output of a show cdp neighbors command issued from R2?

A. R2 and R3

B. R1 and R3

C. R3 and S2

D. R1, S1, S2, and R3

E. R1, S1, S2, R3, and S3

Answer: C

Explanation:

A Cisco device enabled with CDP sends out periodic interface updates to a multicast address in order to make itself known to neighbors. Since it is a layer two protocol, these packets are not routed. So the devices detected would be immediate connected neighbors.

Question No: 6

What is the subnet address for the IP address 172.19.20.23/28?

A. 172.19.20.0

B. 172.19.20.15

C. 172.19.20.16

D. 172.19.20.20

E. 172.19.20.32

Answer: C

Explanation:

From the /28 we can get the following:

Increment: 16 (/28 = 11111111.11111111.11111111.11110000)

Network address: 172.19.20.16 (because 16 < 23)

Broadcast address: 172.16.20.31 (because 31 = 16 + 16 u2013 1)

Question No: 7

What is the bandwidth on the WAN interface of Router 1?

A. 16 Kbit/sec

B. 32 Kbit/sec

C. 64 Kbit/sec

D. 128 Kbit/sec

E. 512 Kbit/sec

F. 1544 Kbit/sec

Answer: A

Explanation:

Use the u201cshow interface s0/0u201d to see the bandwidth set at 16 Kbit/sec.

The show interface s0/0 command results will look something like this and the bandwidth will be represented by the "BW" on the fourth line as seen below where BW equals 1544 Kbits/sec.

R2#show interface serial 0/0 Serial0/0 is up, line protocol is down Hardware is GT96K Serial

Internet address is 10.1.1.5/30

MTU 1500 bytes, BW 1544 Kbit/sec, DLY 20000 uses.

Question No: 8

The network manager has requested a 300-workstation expansion of the network. The workstations are to be installed in a single broadcast domain, but each workstation must have its own collision domain. The expansion is to be as cost-effective as possible while still meeting the requirements.

Which three items will adequately fulfill the request? (Choose three).

A. One IP subnet with a mask of 255.255.254.0

B. Two IP subnets with a mask of 255.255.255.0

C. Seven 48-port hubs

D. Seven 48-port switches

E. One router interface

F. Seven router interfaces

Answer: A,D,E

Explanation:

To support 300 workstations in a single broadcast domain, we need to use a subnet mask which supports 512 hosts = 29-> /23 or 255.255.254.0 in decimal form -> A is correct.

If we use 48-port switches we need 300/48 = 6.25 -> seven 48-port switches are enough because we also need trunking between them -> D is correct.

We only need one router interface and it is connected with one of seven switches -> E is correct.

Question No: 9

A network administrator is trying to add a new router into an established OSPF network. The networks attached to the new router do not appear in the routing tables of the other OSPF routers. Given the information in the partial configuration shown below, what configuration error is causing this problem?

Router(config)# router ospf 1

Router(config-router)# network 10.0.0.0 255.0.0.0 area 0

A. The process id is configured improperly.

B. The OSPF area is configured improperly.

C. The network wildcard mask is configured improperly.

D. The network number is configured improperly.

E. The AS is configured improperly.

F. The network subnet mask is configured improperly.

Answer: C

Explanation:

When configuring OSPF, the mask used for the network statement is a wildcard mask similar to an access list. In this specific example, the correct syntax would have been u201cnetwork 10.0.0.0 0.0.0.255 area 0.u201d

Question No: 10

Refer to the graphic.

R1 is unable to establish an OSPF neighbor relationship with R3. What are possible reasons for this problem? (Choose two.)

A. All of the routers need to be configured for backbone Area 1.

B. R1 and R2 are the DR and BDR, so OSPF will not establish neighbor adjacency with R3.

C. A static route has been configured from R1 to R3 and prevents the neighbor adjacency from being established.

D. The hello and dead interval timers are not set to the same values on R1 and R3.

E. EIGRP is also configured on these routers with a lower administrative distance.

F. R1 and R3 are configured in different areas.

Answer: D,F

Explanation:

This question is to examine the conditions for OSPF to create neighborhood.

So as to make the two routers become neighbors, each router must be matched with the following items:

1. The area ID and its types;

2. Hello and failure time interval timer;

3. OSPF Password (Optional);

Question No: 11

What should be part of a comprehensive network security plan?

A. Allow users to develop their own approach to network security.

B. Physically secure network equipment from potential access by unauthorized individuals.

C. Encourage users to use personal information in their passwords to minimize the likelihood of passwords being forgotten.

D. Delay deployment of software patches and updates until their effect on end-user equipment is well known and widely reported.

E. Minimize network overhead by deactivating automatic antivirus client updates.

Answer: B

Explanation:

From Cisco CCENT Exam Essentials study guide by Todd Lammle:

Know what the first part of a comprehensive network security plan is. The first part of your comprehensive network security plan is to physically secure network equipment from potential access by unauthorized individuals.

List the recommended ways of protecting network devices from outside network security threats. Use a firewall to restrict access from the outside to the network devices, and use SSH or another encrypted and authenticated transport to access device configurations.

Reference:

CCENT Cisco Certified Entry Networking Technician Study Guide: (ICND1 Exam 640-822), 2nd Edition

by Todd Lammle Published by Sybex, 2013

Question No: 12

Refer to the exhibit.

Which two statements are true about the loopback address that is configured on RouterB? (Choose two.)

A. It ensures that data will be forwarded by RouterB.

B. It provides stability for the OSPF process on RouterB.

C. It specifies that the router ID for RouterB should be 10.0.0.1.

D. It decreases the metric for routes that are advertised from RouterB.

E. It indicates that RouterB should be elected the DR for the LAN.

Answer: B,C

Explanation:

A loopback interface never comes down even if the link is broken so it provides stability for

the OSPF process (for example we use that loopback interface as the router-id) - The router-ID is chosen in the order below:

+ The highest IP address assigned to a loopback (logical) interface.

+ If a loopback interface is not defined, the highest IP address of all active routeru2021s physical interfaces will be chosen.

-> The loopback interface will be chosen as the router ID of RouterB -