ICND1 &#38; ICND2

Other lab-sims might appear in the real ICND 1 exam, read and understand them if you have enough time!

Share your ICND2 Experience

9tutq — Wed, 20 Apr 2011 14:40:23 +0000

Please share with us your experience after taking the exam ICND2, your materials, the way you learned, your recommendations…

Please don’t post links to copyrighted work here!

Implementation SIM 2

9tutq — Sat, 16 Apr 2011 13:50:34 +0000

This topology contains 3 routers and 1 switch. Complete the topology.

Drag the appropriate device icons to the labeled Device
Drag the appropriate connections to the locations labeled Connections.
Drag the appropriate IP addresses to the locations labeled IP address

(Hint: use the given host addresses and Main router information)
To remove a device or connection, drag it away from the topology.

Use information gathered from the Main router to complete the configuration of any additional routers. No passwords are required to access the Main router. The config terminal command has been disabled for the HQ router. The router does not require any configuration.

Configure each additional router with the following:

Configure the interfaces with the correct IP address and enable the interfaces.
Set the password to allow console access to consolepw
Set the password to allow telnet access to telnetpw
Set the password to allow privilege mode access to privpw

Note: Because routes are not being added to the configurations, you will not be able to ping through the internetwork.
All devices have cable autosensing capabilities disabled.
All hosts are PC’s

Answer and explanation:

Specify appropriate devices and drag them on the “Device” boxes

For the device at the bottom-right box, we notice that it has 2 interfaces Fa0/2 and Fa0/4; moreover the link connects the PC on the right with the device on the bottom-right is a straight-through link -> it is a switch

The question stated that this topology contains 3 routers and 1 switch -> two other devices are routers

Place them on appropriate locations as following:

(Host D and host E will be automatically added after placing two routers. Click on them to access neighboring routers)

Specify appropriate connections between these devices:

+ The router on the left is connected with the Main router through FastEthernet interfaces: use a crossover cable
+ The router on the right is connected with the Main router through Serial interfaces: use a serial cable
+ The router on the right and the Switch: use a straight-through cable
+ The router on the left and the computer: use a crossover cable

(To remember which type of cable you should use, follow these tips:

- To connect two serial interfaces of 2 routers we use serial cable
– To specify when we use crossover cable or straight-through cable, we should remember:
Group 1: Router, Host, Server
Group 2: Hub, Switch
One device in group 1 + One device in group 2: use straight-through cable
Two devices in the same group: use crossover cable

For example: we use straight-through cable to connect switch to router, switch to host, hub to host, hub to server… and we use crossover cable to connect switch to switch, switch to hub, router to router, host to host… )

Assign appropriate IP addresses for interfaces:

From Main router, use show running-config command:

(Notice that you may see different IP addresses in the real CCNA exam, the ones shown above are just used for demonstration)

From the output we learned that the ip address of Fa0/0 interface of the Main router is 192.168.152.177/28. This address belongs to a subnetwork which has:

Increment: 16 (/28 = 255.255.255.240 or 1111 1111.1111 1111.1111 1111.1111 0000)
Network address: 192.168.152.176 (because 176 = 16 * 11 and 176 < 177)
Broadcast address: 192.168.152.191 (because 191 = 176 + 16 – 1)

And we can pick up an ip address from the list that belongs to this subnetwork: 192.168.152.190 and assign it to the Fa0/0 interface the router on the left

Use the same method for interface Serial0/0 with an ip address of 192.168.152.161

Increment: 16
Network address: 192.168.152.160 (because 160 = 16 * 10 and 160 < 161)
Broadcast address: 192.168.152.175 (because 176 = 160 + 16 – 1)

-> and we choose 192.168.152.174 for Serial0/0 interface of the router on the right

Interface Fa0/1 of the router on the left

IP (of the computer on the left) : 192.168.152.129/28

Increment: 16
Network address: 192.168.152.128 (because 128 = 16 * 8 and 128 < 129)
Broadcast address: 192.168.152.143 (because 143 = 128 + 16 – 1)

-> we choose 192.168.152.142 from the list

Interface Fa0/0 of the router on the right

IP (of the computer on the left) : 192.168.152.225/28

Increment: 16
Network address: 192.168.152.224 (because 224 = 16 * 14 and 224 < 225)
Broadcast address: 192.168.152.239 (because 239 = 224 + 16 – 1)

-> we choose 192.168.152.238 from the list

Let’s have a look at the picture below to summarize

Configure two routers on the left and right with these commands:

Router1 = router on the left

Assign appropriate IP addresses to Fa0/0 & Fa0/1 interfaces:

Router1>enable
Router1#configure terminal
Router1(config)#interface fa0/0
Router1(config-if)#ip address 192.168.152.190 255.255.255.240
Router1(config-if)#no shutdown

Router1(config-if)#interface fa0/1
Router1(config-if)#ip address 192.168.152.142 255.255.255.240
Router1(config-if)#no shutdown

Set passwords (configure on two routers)

+ Console password:

Router1(config-if)#exit
Router1(config)#line console 0
Router1(config-line)#password consolepw
Router1(config-line)#login
Router1(config-line)#exit

+ Telnet password:

Router1(config)#line vty 0 4
Router1(config-line)#password telnetpw
Router1(config-line)#login
Router1(config-line)#exit

+ Privilege mode password:

Router1(config)#enable password privpw

Save the configuration:

Router1(config)#exit
Router1#copy running-config startup-config

Configure IP addresses of Router2 (router on the right)

Router2>enable
Router2#configure terminal
Router2(config)#interface fa0/0
Router2(config-if)#ip address 192.168.152.238 255.255.255.240
Router2(config-if)#no shutdown

Router2(config-if)#interface serial0/0
Router2(config-if)#ip address 192.168.152.174 255.255.255.240
Router2(config-if)#no shutdown

and set console, telnet and privilege mode passwords for Router2 as we did for Router1, remember to save the configuration when you finished

Other lab-sims in the ICND 1 Exam:

Other lab-sims might appear in the real ICND 1 exam, read and understand them if you have enough time!

Implementation SIM

9tutq — Fri, 15 Apr 2011 13:49:17 +0000

Question:

You have been hired by PC Consultants Incorporated to document the layout of the network. Complete the following tasks:
Complete the network topology shown in the graphic by dragging the labels below with the appropriate router types, interface types and IP addresses to the graphic. Find the information you need by using the router console attached to the Home router.

Answer and Explanation:

First we have to find out the types of these routers to place them in correct positions by using show cdp neighbors command on HOME router:

There are 3 columns we should pay more attention to:

+ Local Intrfce (Local Interface): the interface on the device you are using “show cdp neighbors” command. In this case it is the interface of HOME router

+ Platform: the platform of neighbor device

+ Port ID: the neighbor device’s port or interface which links to the HOME router

From the exhibit, the “Local Interface”, “Platform” and “Port ID” columns, we can identify where these four routers should be placed and their corresponding associated ports

Finally, we need to identify the IP addresses of four interfaces on neighboring routers using show running-config command:

And we can easily assign corresponding ip addresses to four neighbor routers, which are on the same network with HOME router’s interfaces

Please remember in the real CCNA Exam the routers’ types, ip addresses and interfaces may be different! So make sure you understand how it works!

Other lab-sims in the ICND 1 Exam:

Other lab-sims might appear in the real ICND 1 exam, read and understand them if you have enough time!

RIPv2 SIM

9tutq — Wed, 13 Apr 2011 13:48:10 +0000

Question:

Central Florida Widgets recently installed a new router in their Apopka office. Complete the network installation by performing the initial router configurations and configuring RIPv2 routing using the router command line interface (CLI) on the Apopka router.

Configure the router per the following requirements:

Name of the router is Apopka
Enable-secret password is cisco10
The password to access user EXEC mode using the console is RouterPass
The password to allow telnet access to the router is scan90

IPv4 addresses must be configured as follows:
Ethernet network 209.165.201.0/27 – router has second assignable host address in subnet.
Serial network is 192.0.2.128/28 – router has last assignable host address in the subnet. Interfaces should be enabled.
Routing protocol is RIPv2.

(Notice: In the real exam the name, passwords, IP addresses and the positions of the assignable host addresses might be different)

Instruction:

To configure the router (Apopka) click on the console host icon that is connected to a router by a serial console cable (shown in the diagram as a dashed black line).

Each of the windows can be minimized by clicking on the [-]. You can also reposition a window by dragging it by the title bar.
The “Tab” key and most commands that use the “Control” or “Escape” keys are not supported and are not necessary to complete this simulation. The help command does not display all commands of the help system.

Answer and Explanation:

1) Name the router:

Router>enable
Router#config terminal
Router(config)#hostname Apopka

2) Enable-secret password (cisco10):

Apopka(config)#enable secret cisco10

3) Set the console password to RouterPass:

Apopka(config)#line console 0
Apopka(config-line)#password RouterPass
Apopka(config-line)#login
Apopka(config-line)#exit

4) Set the Telnet password to scan90:

Apopka(config)#line vty 0 4
Apopka(config-line)#password scan90
Apopka(config-line)#login
Apopka(config-line)#exit

5) Configure Ethernet interface (on the right) of router Apopka:

The subnet mask of the Ethernet network 209.165.201.0 is 27. From this subnet mask, we can find out the increment by converting it into binary form, that is /27 = 1111 1111.1111 1111.1111 1111.1110 0000. Pay more attention to the last bit 1 because it tells us the increment, using the formula:
Increment = 2^{place of the last bit 1 (starts counting from 0,from right to left)}, in this case increment = 2⁵= 32. Therefore:

Increment: 32
Network address: 209.165.201.0
Broadcast address: 209.165.201.31 (because 209.165.201.32 is the second subnetwork, so the previous IP – 209.165.201.31 – is the broadcast address of the first subnet).

-> The second assignable host address of this subnetwork is 209.165.201.2/27

Assign the second assignable host address to Fa0/0 interface of Apopka router:

Apopka(config)#interface Fa0/0
Apopka(config-if)#ip address 209.165.201.2 255.255.255.224
Apopka(config-if)#no shutdown
Apopka(config-if)#exit

6) Configure Serial interface (on the left) of router Apopka:

Using the same method to find out the increment of the Serial network:

Serial network 192.0.2.128/28:

Increment: 16 (/28 = 1111 1111.1111 1111.1111 1111.1111 0000)
Network address: 192.0.2.128 (because 8 * 16 = 128 so 192.0.2.128 is also the network address of this subnet)
Broadcast address: 192.0.2.143

-> The last assignable host address in this subnet is 192.0.2.142/28.

Assign the last assignable host address to S0/0/0 interface of Apopka router:

Apopka(config)#interface S0/0/0 (or use interface S0/0 if not successful)
Apopka(config-if)#ip address 192.0.2.142 255.255.255.240
Apopka(config-if)#no shutdown
Apopka(config-if)#exit

7) Configure RIP v2 routing protocol:

Apopka(config)#router rip
Apopka(config-router)#version 2
Apopka(config-router)#network 209.165.201.0
Apopka(config-router)#network 192.0.2.128
Apopka(config-router)#end

Save the configuration:

Apopka#copy running-config startup-config

Finally, you should use the ping command to verify all are working properly!

Other lab-sims in the ICND 1 Exam:

Other lab-sims might appear in the real ICND 1 exam, read and understand them if you have enough time!

Hotspot

9tutq — Fri, 08 Apr 2011 13:43:21 +0000

Here you will find answers to hotspot questions in ICND 1 exam

Refer to the topology. Using the information shown, answer the five questions shown on the Questions tab.

Question 1:

On which router should a default route be configured?

A – on the ISP router
B – on R1
C – on R2
D – on R3
E – on R4

Answer: B

Question 2:

With all links operational and all routers converged, which of the following describes the messaging between routers?

A – Hellos are sent every five seconds.
B – Multicasts are sent every 60 seconds.
C – Broadcasts are sent every 30 seconds.
D – No messaging unless the topology changes.

Answer: C

Question 3:

Which of the following describes the route update process if the interface from R4 connected to LAN 4 goes down?

A – No updates occur
B – R4 tells both R1 and R3 the network not accessible. Both R3 and R1 update R2.
C – R4 tells only R1 the network is not accessible. R1 updates R2 and R2 updates R3.
D – R4 tells only R3 the network is not accessible. R3 updates R2 and R2 updates R1.

Answer: B

Question 4:

Why would RIP be used rather than static routes on R1, R2, R3, and R4?

A – RIP creates more accurate than static routes.
B – RIP uses less network resources than do static routes.
C – RIP is supported by more different vendors equipment than static routes.
D – RIP requires less configuration to automatically adjust when links go down than static routes.

Answer: D

Question 5:

On which router should a static route be configured?

A – on the ISP router
B – on R1
C – on R2
D – on R3
E – on R4

Answer: A

Operations

9tutq — Tue, 05 Apr 2011 13:24:24 +0000

Here you will find answers to operation questions in ICND 1 exam

Question 1:

Refer to the exhibit. The junior network support staff provided the diagram as a recommended configuration for the first phase of a four-phase network expansion project. The entire network expansion will have over 1000 users on 14 network segments and has been allocated this IP address space:

192.168.1.1 through 192.168.5.255
192.168.100.1 through 198.168.100.255

What are three problems with this design? (Choose three)

A – The AREA 1 IP address space is inadequate for the number of users.
B – The AREA 3 IP address space is inadequate for the number of users.
C – AREA 2 could use a mask of /25 to conserve IP address space.
D – The network address space that is provided requires a single network-wide mask.
E – The router-to-router connection is wasting address space.
F – The broadcast domain in AREA 1 is too large for IP to function.

Answer: A C E

Question 2:

Refer to the exhibit. A technician is testing connection problems in the internetwork. What is the problem indicated by the output from HostA?

A – The routing on Router2 is not functioning properly.
B – An access list is applied to an interface of Router3.
C – The Fa0/24 interface of Switch1 is down.
D – The gateway address of HostA is incorrect or not configured.

Answer: D

Explanation:

When trying to ping the IP 192.168.3.254,you received the replies from that IP. It means that you can reach the Fa0/0 interface of Router1. But notice that the IP of host A (192.168.3.1/24) and the IP of the Fa0/0 interface of Router 1 (192.168.3.254/24) are on the same network. So you don’t need a gateway address configured on HostA. Therefore you can’t conclude the gateway address of HostA was configured correctly.

Lately, you tried to use the tracert command to reach another network (192.168.4.7). In this case, a gateway address was required for reaching the network of hostB. But the result told that “Destination host unreachable” – means that Host A can not find a route to Host B -> The gateway address of Host A was incorrect (something other than 192.168.3.254) or not configured is a possibility.

A and B are incorrect because if there is a mis-configuration on Router 2 or Router 3 (while Router 1 is configurated correctly), you will see at least one successful line when using tracert command likes the bold line below:

PC>tracert 192.168.4.7

Tracing route to 192.168.4.7 over a maximum of 30 hops:

1 62 ms 62 ms 46 ms 192.168.3.254
2 * * * Request timed out.

C is incorrect because we can ping Router 1 -> port Fa0/24 on Switch 1 was turned on and running correctly.

Question 3:

Refer to the exhibit. The internetwork is using subnets of the address 192.168.1.0 with a subset mask of 255.255.255.224. The routing protocol in use is RIP version 1. Which address could be assigned to the FastEthernet interface on RouterA?

A – 192.168.1.31
B – 192.168.1.64
C – 192.168.1.127
D – 192.168.1.190
E – 192.168.1.192

Answer: D

Explanation:

255.255.255.224 = 1111 1111.1111 1111.1111 1111.1110 0000 (binary form)

Increment: 32

First subnetwork: 192.168.1.0 -> 192.168.1.31 (A is incorrect because 192.168.1.31 is a broadcast address)
Second subnetwork: 192.168.1.32 -> 192.168.1.63
Third subnetwork: 192.168.1.64 -> 192.168.1.95 (B is incorrect because 192.168.1.64 is a network address)
Fourth subnetwork: 192.168.1.96 -> 192.168.1.127 (C is incorrect because 192.168.1.127 is a broadcast address)
Fifth subnetwork: 192.168.1.128 -> 192.168.1.159
Sixth subnetwork: 192.168.1.160 -> 192.168.1.191 (D is correct because 192.168.1.190 is the last assignable host address of this subnetwork)
Seventh subnetwork: 192.168.1.192 -> 192.168.1.224 (E is incorrect because 192.168.1.192 is a network address)

Question 4:

Refer to the exhibit. For security reasons, information about RTA, including platform and IP addresses, should not be accessible from the Internet. This information should, however, be accessible to devices on the internal networks of RTA. Which command or series of commands will accomplish these objectives?

A – RTA(config)#no cdp run
B – RTA(config)#no cdp enable
C – RTA(config)#interface s0/0
RTA(config-if)#no cdp run
D – RTA(config)#interface s0/0
RTA(config-if)#no cdp enable

Answer: D

Question 5:

Refer to the exhibit, PC1 pings PC2. What three things will CORE router do with the data that is received from PC1? (Choose three)

A – The data frames will be forwarded out interface FastEthernet0/1 of CORE router.
B – The data frames will be forwarded out interface FastEthernet1/0 of CORE router.
C – CORE router will replace the destination IP address of the packets with the IP address of PC2.
D – CORE router will place the MAC address of PC2 in the destination MAC address of the frames.
E – CORE router will put the IP address of the forwarding FastEthernet interface in the place of the source IP address in the packets.
F – CORE router will put the MAC address of the forwarding FastEthernet interface in the place of the source MAC address.

Answer: B D F

Subnetting Questions

9tutq — Fri, 01 Apr 2011 13:24:06 +0000

Here you will find answers to subnetting questions in ICND 1 exam

Note: If you are not sure about subnetting, please read my Subnetting tutorial.

Question 1:

Refer to the exhibit. The goal of this network design is to provide the most efficient use of IP address space in a network expansion. Each circle defines a network segment and the number of users required on that segment. An IP subnetwork number and default gateway address are shown for each segment.

What are three problems with the network design as shown? (Choose three)

A – Interface fa0/3 has an IP address that overlaps with network 10.1.3.0/30.
B – Interface fa0/1 has an invalid IP address for the subnet on which it resides.
C – Interface fa0/2 has an invalid IP address for the subnet on which it resides.
D – Network 10.1.2.0/25 requires more user address space.
E – Network 10.1.3.128/25 requires more user address space.
F – The IP subnet 10.1.1.0/30 is invalid for a segment with a single server.

Answer: A B D

Question 2:

If an ethernet port on a router was assigned an IP address of 172.16.112.1/20, what is the maximum number of hosts allowed on this subnet?

A – 1024
B – 2046
C – 4094
D – 4096
E – 8190

Answer: C

Question 3:

Refer to the exhibit. The internetwork is using subnets of the address 192.168.1.0 with a subnet mask of 255.255.255.224. The routing protocol in use is RIP version 2. Which address could be assigned to the FastEthernet interface on RouterA?

A – 192.168.1.31
B – 192.168.1.64
C – 192.168.1.127
D – 192.168.1.190
E – 192.168.1.192

Answer: D

Question 4:

Refer to the exhibit. HostA cannot ping HostB. Assuming routing is properly configured, what could be the cause of this problem?

Answer: D

Drag and Drop Questions

9tutq — Tue, 29 Mar 2011 13:23:34 +0000

Here you will find answers to drag and drop questions in ICND 1 exam

Question 1:

Drag the appropriate command on the left to the configuration task it accomplishes (not all options are used)

Answer:

1) service password-encryption
2) line console 0
password friendS0nly
3) enable secret noWay1n4u
4) line vty 0 4
password 2hard2Guess
5) enable password uwi11NeverNo

Question 2:

Construct the command sequence to configure an IP address on a serial interface (not all options are used)

Answer:

1) Hub# configure terminal
2) Hub(config)# interface s0/0
3) Hub(config-if)# ip address 10.8.5.255 255.255.252.0
4) Hub(config-if)# no shutdown
5) Hub(config-if)# description T1 to WAN

Explanation:

One thing interesting in the answers is that the command ip address “10.8.5.255 255.255.252.0″ (answer 3) is correct because 10.8.5.255 255.255.255.0 is not a broadcast address. Let’s analyze this case a bit closer:

Increment: 4 for the third octet (255.255.252.0 = 1111 1111.1111 1111.1111 1100.0000 0000)
First subnetwork range: 10.8.0.0 to 10.8.3.255
Second subnet range: 10.8.4.0 to 10.8.7.255
…

Therefore 10.8.3.255 and 10.8.7.255 are the broadcast addresses but not 10.8.5.255. So we can assign this address to s0/0 interface.

( Notice that the command Hub(config)# ip address 172.16.20.21 255.255.255.0 is only correct only if it is in interface mode, which is Hub(config-if)# )

Question 3:

Drag the commands on the left to the appropriate functions on the right (Not all options are used)

Answer:

1) ipconfig /all
2) tracert
3) telnet
4) ping 127.0.0.1
5) arp -a

Drag and Drop Questions 2

9tutq — Mon, 28 Mar 2011 13:23:06 +0000

Here you will find answers to ICND 1 – Drag and Drop Questions Part 2

Question 1

As a CCNA candidate, you should master the functions of various commands. Look at the following items, some commands are listed on the left. The related roles are listed on the right in a wrong sequence. Please match them together. (Not all options are used)

Answer:

1) Router#copy tftp flash: replace the IOS image
2) Router#copy flash tftp: backup the current IOS image
3) Router#copy running-config tftp: make a backup copy of configuration in RAM
4) Router#copy running-config startup-config: make the configuration in RAM the configuration the router will use on startup
5) Router#copy tftp running-config: merge a backup configuration with the configuration in RAM

Explanation

First please notice that by saying “replace” we often mean changes to NVRAM and TFTP while saying “merge” or “add” we mean changes to RAM. Next we should review the syntax of “copy” command:

Syntax: copy

1) By default, the flash memory in a router is used to store the Cisco IOS image so the requirement “replace the IOS image” means that moving file somewhere to the flash memory. In the left columns we only have one choice which has the flash as the destination ->copy tftp flash.

2) Same explanation as above, when saying “backup the current IOS image” the flash takes the role as the source ->copy flash tftp. And “backup” means we should copy it to somewhere like tftp server, CDROM…

3) The running-config is stored in the RAM so “make a backup copy of configuration in RAM” means copy running configuration from RAM so backup server (tftp) -> copy running-config tftp

4) “copy running-config startup-config” is a very common command so no more explanation needed.

5) After solving 4 boxes above, we only have two choices left: “copy tftp running-config” & “copy flash running-config”. The bottom-right box says “merge a backup configuration” so it should be the tftp server and the command here is copy tftp running-config.

Wireless Questions

9tutq — Fri, 25 Mar 2011 16:21:53 +0000

Here you will find answers to Wireless Questions – Part 1

If you are not sure about Wireless, please read my Wireless tutorial and Basic Wireless Terminologies

Question 1

Which wireless LAN design ensures that a mobile wireless user will not lose connectivity when moving from one access point to another on the WLAN?

A. Utilizing MAC address filtering to allow the client MAC address to authenticate with the surrounding APs
B. Using adapters and access points manufactured by the same company
C. Overlapping the wireless cell coverage by at least 10%
D. Configuring all access points to use the same channel

Answer: C

Explanation

By using more than one Access Point (AP) we can create overlapping cells to allow roaming in a larger area. But we have to ensure that two APs must have at least 10% coverage overlap and they use non-overlapping channels.

Question 2

You need to troubleshoot an interference issue with the wireless LAN. Which two devices can interfere with the operation of this network because they operate on similar frequencies? (Choose two)

A. Microwave oven
B. AM radio
C. Toaster
D. Copier
E. Cordless phone
F. IP phone
G. Ipod

Answer: A E

Explanation

Microwave oven and cordless phone radiate energy in the 2.4 GHz unlicensed band so they can interfere with some WLAN standards. As the result of that, you can’t hear clearly on the phone or can’t surf web.

Question 3

Which of the following data network would you implement if you wanted a wireless network that had a relatively high data rate, but was limited to very short distances?

A. Broadband personal comm. Service (PCS)
B. Broadband circuit
C. Infrared
D. Spread spectrum
E. Cable

Answer: C

Explanation

Infrared typically requires a line-of-sight (your TV remote control, for example) which means that it is limited to very short distances. I am not sure if it is considered “relative high data rate” but infrared can transfer up to 4Mpbs.

Question 4

You need to add a wireless access point to a new office. Which additional configuration step is necessary in order to connect to an access point that has SSID broadcasting disabled?

A. Configure open authentication on the AP and the client
B. Set the SSID value in the client software to public
C. Set the SSID value on the client to the SSID configured on the AP
D. Configure MAC address filtering to permit the client to connect to the AP

Answer: C

Explanation

Service Set Identifier (SSID) is the term to identify a WLAN. In most cases SSID is broadcast by the AP, the user only needs to select that SSID and provides a correct password to access it. But in some cases for security reason, the SSID can be disabled. Users can only access to that network if they type both SSID and password correctly.

Question 5

You need to secure a new access point on the a wireless network. Which two practices help secure the configuration utilities on wireless access points from unauthorized access? (Choose two)

A. Changing the default SSID value
B. Configuring traffic filtering
C. Changing the mixed mode setting to single mode
D. Configuring a new administrator password
E. Assigning a private IP address to the AP

Answer: A D

Explanation

To improve security, you should change the default SSID value on your AP. For example, Linksys routers (which are produced by Cisco) typically have an SSID of “linksys” -> A is correct.

In an AP we can configure traffic filtering but it is mainly used for filtering which services clients can use, IP ranges, ports, websites, time access… It has no effect on securing your AP -> B is not correct.

“Mixed mode” here means we can configure AP to allow clients to use different standard like 802.11b, g or n. But setting it to single mode doesn’t have any security protection on it -> C is not correct.

We should also change the administrator password because everyone can access to the admin page of an AP by open a web browser and type the IP address of that AP (for example: http://192.168.1.1). Typically, Linksys Wireless routers have a default username/password of “admin/admin” or “admin/[blank]” which are easily guessed or found out -> D is correct.

We can access the AP by using a private IP address (in the same private network of the AP – 192.168.1.1, for example) -> E is not correct.

Question 6

You need to determine the proper security settings on a new WLAN-capable office. Which encryption type would WPA2 use in this office?

A. PSK
B. AES-CCMP
C. PPK via IV
D. TKIP/MIC
E. None of the other alternatives apply

Answer: B

Explanation

Advanced Encryption Standard (AES) is the cipher system used by RSN. It is the equivalent of the RC4 algorithm used by WPA. However the encryption mechanism is much more complex and does not suffer from the problems associated with WEP. AES is a block cipher, operating on blocks of data 128bits long.

CCMP is the security protocol used by AES. It is the equivalent of TKIP in WPA. CCMP computes a Message Integrity Check (MIC) using the well known, and proven, Cipher Block Chaining Message Authentication Code (CBC-MAC) method. Changing even one bit in a message produces a totally different result.

The AES-CCMP encryption algorithm used in the 802.11i (WPA2) security protocol. It uses the AES block cipher, but restricts the key length to 128 bits. AES-CCMP incorporates two sophisticated cryptographic techniques (counter mode and CBC-MAC) and adapts them to Ethernet frames to provide a robust security protocol between the mobile client and the access point.

Question 7

What is one reason why WPA encryption is preferred over WEP in this network?

A. The WPA key values remain the same until the client configuration is changed.
B. The values of WPA keys can change dynamically while the system is used.
C. The access point and the client are manually configured with different WPA key values.
D. A WPA key is longer and requires more special characters than the WEP key.
E. None of the other alternatives apply

Answer: B

Explanation

Wireless Encryption Protocol (WEP) uses RC4 encryption and a static 64-bit key so it can be easily broken as only 40-bits are encrypted and 24 bits are clear-text IV(Initialization Vector). It was later upgraded to 128-bit, but the IV was still clear text meaning it took slightly longer (minutes) to break-in.

WPA was introduced in 2003 as a replacement for WEP. WPA uses Temporal Key Integrity Protocol (TKIP) to automatically change the keys. TKIP still uses RC4; it just improves how it’s done

Question 8

In an effort to increase security within the wireless network, WPA is being utilized. Which two statements shown below best describe the wireless security standard that is defined by WPA? (Choose two)

A. It requires use of an open authentication method
B. It specifies use of a static encryption key that must be changed frequently to enhance security
C. It includes authentication by PSK
D. It specifies the use of dynamic encryption keys that change each time a client establishes a connection
E. It requires that all access points and wireless devices use the same encryption key
F. WPA works only with Cisc0 access points

Answer: C D

Question 9

You need to configure a new wireless access point for your network. What are three basic parameters to configure an AP? (Choose three)

A. Authentication method
B. RTS/CTS
C. RF channel
D. SSID

Answer: A C D

Explanation

Below lists basic parameters to configure an AP

Wireless Questions 2

9tutq — Thu, 24 Mar 2011 16:19:16 +0000

Here you will find answers to Wireless – Part 2

If you are not sure about Wireless, please read my Wireless tutorial and Basic Wireless Terminologies

Question 1

You have finished physically installing an access point on the ceiling at a newly opened office. At a minimum, which parameter must you configure on the access point in order to allow wireless clients to operate on it?

A. SSID
B. AES
C. TKIP
D. PSK
E. None of the other alternatives apply

Answer: A

Question 2

Part of the wireless LAN is shown below:

What two facts can be determined from the diagram of the WLAN shown above? (Choose two)

A. Access points in each cell must be configured to use channel 1
B. The network diagram represents an extended service set (ESS)
C. The two APs should be configured to operate on different channels
D. The area of overlap of the two cells represents a basic service set (BSS)
E. The area of overlap must be less than 10% of the area to ensure connectivity
F. There are too many hosts on this WLAN

Answer: B C

Question 3

A single 802.11g access point has been configured and installed in the center of a square shaped office. A few wireless users are experiencing slow performance and drops while most users are operating at peak efficiency. From the list below, what are three likely causes of this problem? (Choose three)

A. Null SSID
B. Mismatched TKIP encryption
C. Cordless phones
D. Antenna type or direction
E. Mismatched SSID
F. Metal file cabinets

Answer: C D F

Explanation

802.11g operates in 2.4 GHz ISM band. Some popular devices and technologies can interfere 802.11g signal:

+ Newer cordless phones
+ Bluetooth
+ Microwaves
+ Metal surface (can cause interference)
+ Antenna (can reduce wireless signal)

Question 4

Three access points have been installed and configured to cover a small remote office. What term defines the wireless topology?

A. SSID
B. BSS
C. ESS
D. IBSS
E. ASS

Answer: C

Question 5

Two workers have established wireless communication directly between their wireless laptops. What type of wireless topology has been created by these employees?

A. ESS
B. IBSS
C. SSID
D. BSS

Answer: B

Explanation

Independent Basic Service Set – IBSS (ad hoc mode) does not use an AP. It allows two devices to communicate directly.

Basic Service Set (BSS) is a single wireless LAN created with an AP and all devices that associate with that AP.

Extended Service Set (ESS) consists of multiple APs, allowing roaming in a larger coverage area.

Question 6

802.1b is being utilized in the wireless network. Which spread spectrum technology does the 802.1b standard define for operation in this network?

A. FHSS
B. IR
C. DSSS and FHSS
D. DSSS
E. IR, FHSS and DSSS

Answer: D

Explanation

Frequency Hopping Spread Spectrum (FHSS) uses all frequencies in the band, hopping to different ones. By using slightly different frequencies for consecutive transmissions, a device can hopefully avoid interference from other devices that use the same unlicensed band, succeeding at sending data at some frequencies.

Direct Sequence Spread Spectrum (DSSS) followed as the next general class of encoding type for WLANs. Designed for use in the 2.4 GHz unlicensed band, DSSS uses one of several separate channels or frequencies.

The original 802.11 WLAN standards used FHSS, but the current standards (802.11a, 802.11b, and 802.11g) do not. 802.1b uses DSSS while 802.1a & 802.1g use Orthogonal Frequency Division Multiplexing (OFDM).

(Reference: ICND1 Official Exam Certification Guide)

Question 7

Which IEEE standard is used to define Wi-Fi?

A. IEEE 802.3
B. IEEE 802.5
C. IEEE 802.11h
D. IEEE 802.11c
E. IEEE 802.11

Answer: E

Question 8

An office is using an IEEE 802.11b wireless LAN. What is the maximum data rate specified for this WLAN?

A. 11 mbps
B. 100 mbps
C. 54 mbps
D. 10 mbps
E. 1000 mbps
F. 16 mbps

Answer: A

Explanation

The maximum data rate for popular WLAN standards are listed below:

* IEEE 802.11a: 54 Mbps in the 5.7 GHz ISM band
* IEEE 802.11b: 11 Mbps in the 2.4 GHz ISM band
* IEEE 802.11g: 54 Mbps in the 2.4 GHz ISM band

Share your ICND1 Experience

9tutq — Mon, 16 Aug 2010 13:20:45 +0000

Please share with us your experience after taking the exam ICND1, your materials, the way you learned, your recommendations…

Please don’t post links to copyrighted work here!

Show Configuration Sim

9tutq — Sun, 11 Apr 2010 13:46:10 +0000

This task requires the use of various show commands from the CLI of Router1 to answer 5 multiple-choice questions. This does not require any configuration.

NOTE: The show running-configuration and the show startup-configuration commands have been disabled in this simulation.
To access the multiple-choice questions, click on the numbered boxes on the right of the top panel.
There are 5 multiple-choice questions with this task. Be sure to answer all 5 questions before leaving this item.

Question 1:

What is the subnet broadcast address of the LAN connected to Router1?
A – 192.168.136.15
B -192.168.136.31
C -192.168.136.63
D – 192.168.136.127
E – 255.255.255.255

Answer: A

Explanation:

The “show running-configuration” and “show startup-configuration” have been disabled as stated above so we should use the show ip interface command to get information about the LAN network connected to Router1.

From the output we learn that the ip address of the FastEthernet interface of Router1 is 192.168.136.1 and the subnet mask is /28. Therefore:

Increment: 16 (/28=1111 1111.1111 1111.1111 1111.1111 0000)
Network address: 192.168.136.0
Broadcast address: 192.168.136.15 (15 = 0 + 16 – 1)

-> The broadcast address of this subnetwork is 192.168.136.15

Question 2:

What is the bandwidth on the WAN interface of Router1?
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: E

Explanation:

To find out the bandwidth on the WAN (serial) interface of Router1 we need to use the show interfaces serial 0/0 command:

Therefore the bandwidth on the WAN is 512 Kbit/sec.

Question 3:

What interfaces on Router1 have not had any configurations applied? (Choose two)

A – Ethernet 0
B – FastEthenet 0/0
C – FastEthernet 0/1
D – Serial 0
E – Serial 0/0
F – Serial 0/1

Answer: C F

Explanation:

Use the show ip interface brief to identify what interfaces Router 1 have. Notice that Router1 does not have Ethernet 0 and Serial 0 interfaces. FastEthernet 0/0 and Serial 0/0 were configured with their IP addresses therefore only FastEthernet 0/1 and Serial0/1 have not had any configurations applied.

Question 4:

Including the address on the Router1 FastEthernet interface, how many hosts can have IP addresses on the LAN to which Router1 is connected?
A – 6
B – 14
C – 62
D – 128

Answer: B

Explanation:

The mask address of interface Fa0/0 of Router1 is /28 (as shown in question 1), which has four 0 bits (1111 1111.1111 1111.1111 1111.1111 0000). Therefore there are 2⁴ – 2 = 14 assignable IP addresses for hosts on the LAN.

Question 5:

The hosts in the LAN are not able to connect to the Internet. Which commands will correct this issue?
A – Router1(conf)# interface fa0/0
Router1(conf-if)# no shutdown
B – Routed (conf)# interface fa0/1
Router1(conf-if)# no shutdown
C – Router1(conf)# interface s0/0
Router1(conf-if)# no shutdown
D – Router1(conf)# interface s0/1
Router1(conf-if)# no shutdown
E – Router1(conf)# interface s0/0
Router1(conf-if)# ip address 10.11.12.13 255.255.255.252
F – Router1(conf)# interface s0/1
Routerl (conf-if)# ip address 10.11.12.13 255.255.255.252

Answer: C

Explanation:

We should check the statuses of all the interfaces on Router1 with the show ip interface brief command:

From the output, we learn that the status of Serial0/0 interface which connects to ISP router is currently “administratively down”. This status indicates this interface is shutting down so we need to turn it on.

Other lab-sims in the ICND 1 Exam: