CCNA3 Chap1 practice testanswers

CCNA3 Chapter 1 Practice Test Answers

At which layer of the hierarchical network design would you find switches that use access control lists to implement security?

Core Distribution Access All 3 layers

At which layer of the hierarchical network design would you find switches that use port-based security to control which devices connect to the network?


At which layer of the hierarchical network design would you find switches that do not implement security measures, but switch packets as fast as possible?


At which layer of the hierarchical network design would it be useful to have switches that implement PoE?


At which layer of the hierarchical network design would it be useful to have switches that implement QoS?


SW 23/10/2007 /tt/file_convert/551d9b1c49795964198b4d59/document.doc 1

At which layer of the hierarchical network design is it least important to have a switch whose forwarding rate equals the combined wire speed of all the ports?


At which layer of the hierarchical network design would it be useful to have switches that implement link aggregation?


At which layer of the hierarchical network design are you least likely to find redundancy?


At which layer of the hierarchical network design would a server in a data centre connect to the network?

Core Distribution Access

At which layer of the hierarchical network design are you most likely to find switches that do not have OSI layer 3 features?

Core Distribution Access

What is the reason for not having redundancy at every layer?

Efficiency Availability Scalability Cost


What is link aggregation?

Load balancing across different routes that have the same number of hops

Two or more links acting as a single virtual link with the combined bandwidth

Sending alternate packets on different links Using a single physical interface with subinterfaces to connect to

different devices

What is another name for the core layer of the network?

Vertical cabling Horizontal cabling High-speed backbone WAN link

Which of these processes is an OSI layer 3 process carried out by distribution layer switches?

Routing between VLANs Switching using MAC addresses Link aggregation Provision of PoE

Which feature of network switches is particularly important in a converged network?

Port security Quality of service Link aggregation Modularity

How might a company save money by having a converged network in their new premises rather than having separate data, phone and video networks?

Networking devices designed for converged networks are cheaper They need only one set of network cables installed instead of

three They can re-use all their old PCs, phones and videoconferencing

equipment Management is easier, so they can employ staff with fewer

qualifications

Which type of switch has a chassis into which line cards can be installed? Stackable switch Fixed configuration switch Multilayer switch Modular switch


What is a characteristic of a fixed configuration switch?

You cannot alter the number of ports You cannot alter how it is connected to other switches It has a fixed size of one rack unit It has line cards fixed into its chassis

Which is a desirable characteristic of an access layer switch allocated to a department where there are a large number of computer users?

Multilayer capabilities High port density High latency Ability to route between VLANs

What is special about stackable switches?

They can be fitted easily into a switch cabinet They can be connected through special ports and act as a single

switch They have a modular construction so that they can have extra ports if

required They have a strengthened case that is able to take extra weight

The Catalyst Express 500 switch is the cheapest switch in the Catalyst range. This is a fixed configuration switch with up to 24 10/100 ports and optional PoE. It offers forwarding rates from 8.8 Gb/s to 24 Gb/s, web-based management, and converged data/IP communications support. Where would it best be used?

For home use to allow 3 PCs to share access to a broadband router. The only switch in the network of a small company with 10-15

employees. One of a group of access layer switches providing connectivity for a

single department within a larger company. As a distribution layer switch in a small to medium sized company.

Which features of switches at the core layer promote availability and reliability? (Choose 2)

Redundancy Hot-swappable hardware components Modularity PoE


The network manager analyses the use that the HR department makes of the network: how many workstations they have, what applications they use, which servers they use, how much bandwidth they use. What type of analysis is this?

Traffic Flow Analysis User Communities Analysis Data Store and Servers Analysis Local Department Analysis



An Ethernet network is using CSMA/CD and a collision has occurred. Which host will be the next to transmit data?

The host that was the first to detect the collision. The host that was the first to transmit data that was involved in the

collision. A host that has data to transmit and whose backoff period expires

first. A host that has data to transmit and is holding the token at the time.

What is necessary for an Ethernet network to be free of collisions?

The network must use fibre optic cable. The network must use layer 2 switches. Hubs must be replaced with switches to reduce the number of collision

domains. The network must use full duplex transmission and be fully

switched.

Which frames are flooded by a switch through all ports except the incoming port?

Broadcast frames, multicast frames and frames where the destination MAC address is not in the MAC address table.

Unicast frames, multicast frames and frames where the source MAC address is not in the MAC address table.

Broadcast frames, multicast frames and frames where there is no known switch port that matches the source MAC address.

Broadcast frames, unicast frames and frames where there is no known switch port that matches the destination MAC address.

Where does a switch get the data to build up its MAC address table?

From the destination MAC addresses of incoming frames. From the source MAC addresses of incoming frames. From the destination MAC addresses of outgoing frames. From the source MAC addresses of outgoing frames.


How does the default behaviour of a switch differ from the default behaviour of a router when a broadcast message arrives?

There is no difference. They both forward the message through all ports except the incoming port.

There is no difference. They both drop the broadcast message. The switch forwards the message through all ports except the

incoming port, while the router drops it. The router forwards the message through all ports except the incoming

port, while the switch drops it.

Another name for the MAC address table of a switch is the:

ARP table CAM table CAD table CDP table

How many collision domains?

2 3 9 10 12

And how many broadcast domains?

2 3 9 10 12


Why are routers still required for Ethernet networks in some cases even though multilayer switches are available that operate at layer 3?

Routers operate more quickly than layer 3 switches. Routers are generally better at making connections to WANs. Switches cannot carry out routing using IP addresses. Layer 3 switches cannot split up broadcast domains.

Which is true of port based buffering but not of shared buffering in a switch?

Large frames can be accommodated more easily. Frames are linked dynamically to their exit port and sent as soon as it

is available. A frame may be delayed if the frame ahead of it in the queue is

waiting for its exit port to become available. Buffer memory is allocated flexibly as it is required.

Which mode of switching reads the whole frame and carries out a cyclic redundancy check?

Fast forward Cut through Fragment free Store and forward

If you type in a switch command, leave a space and then type ?, what do you get?

A list of other commands that can be typed in that mode. A list of parameters that can follow the command. An error message A repeat of the previously typed command

If you have used the up arrow key or Ctrl + P to show several previous commands from the command history, you can work back and show the later commands by pressing the down arrow key or:

Ctrl + N Ctrl + C Ctrl + D Ctrl + V

Where is the running configuration held?

Flash ROM RAM NVRAM


Which command needs to be in a switch configuration in order for an administrator to use its web based interface?

www interface http server enable ip http server ip http activate

Which command is needed if the web based interface of a switch is to be accessed by a username and password specified in the command:userid tech password cisco.

ip http authentication aaa ip http authentication enable ip http authentication local ip http authentication tacacs

Why is it advisable to put a switch IP address on some interface other than VLAN 1?

It is not possible to put an IP address on a VLAN interface. VLAN 1 cannot be associated with a physical interface in order for

messages to be sent. VLAN 99 is the only interface that allows access to the web based

interface. It is more secure to use a different VLAN interface for

management purposes.

Which is the correct option for configuring a switch with the address of its local router so that it can be accessed from a remote network?

SW1#default-gateway 172.16.0.1 255.255.255.0 SW1(config)# default-gateway 172.16.0.1 255.255.255.0 SW1(config-if)# default-gateway 172.16.0.1 255.255.255.0 SW1(config-line)# default-gateway 172.16.0.1 255.255.255.0

You capture a running configuration that includes the line:enable secret 5 859D23N4BA56What will happen if you put this configuration back on a router without making any changes in this line?

All passwords will be encrypted. You will need to enter 859D23N4BA56 in order to reach privileged

exec mode. The enable password must be used instead of enable secret. The router will not accept the configuration.


You configure both a login banner and a message of the day banner on a switch. What do you see when you make a console connection to the switch?

The motd banner, then the login banner, then the prompt for a password.

The login banner, then the motd banner, then the prompt for a password.

The motd banner, then the prompt for a password, then the login banner.

The login banner, then the prompt for a password, then the motd banner.

What is the effect of entering the commands:SW1(config)#line vty 0 15SW1(config-line)#transport input SSH

You will not be able to Telnet to the switch. It allows you to use SSH as well as Telnet for remote access to the

switch CLI. All traffic received by all switch ports will be encrypted. The switch will be able to receive SSH messages but not send them.

A port has been configured to learn a dynamic secure address. How can you ensure that this address is still known after the switch reboots?

Save the MAC address table. Reconfigure the port with a static address. Enable sticky learning then save the running configuration. Change the security violation mode.

By default, how many secure addresses can a switch port learn?

1 2 10 1024

Why do you give the command switchport mode access before setting security on a port?

The command is needed in order for any device to access the port. The default switchport mode is dynamic desirable, which does not

allow security to be configured. The default switchport mode is trunk, which does not allow security to

be configured. This is another way of giving the no shutdown command.


Which type of switchport security is being configured by the command:SW1(config-if)#switchport port-security mac-address 000c.7612.3b82

Static Dynamic Sticky Protect



The network shown in the diagram has just been configured and none of the switches yet has any entries in its bridging table. Workstation A1 sends out a broadcast ARP request. What will happen? (Choose two)

All nine workstations will receive the ARP request. Only Switch A will receive the ARP request. All devices on VLAN 1 will receive the ARP request. Workstations connected to Switch A will receive the ARP request. Switch A will put the MAC address of workstation A1 into its

bridging table. The router will flood the ARP request to all VLANs.

Workstation A1 in the diagram sends a unicast frame to workstation C2. What must happen in order for C2 to receive the frame?

Nothing. VLAN trunking will ensure that C2 receives the frame. C2 cannot receive the frame because it is on a different VLAN from A1. C2 cannot receive the frame because it is attached to a different switch

from A1. The router must be configured so that it can route between the

VLANs. Switch A must be configured to route frames between the VLANs.

How many VLANs can be configured on a Catalyst switch?

9925510244096


Switch A

Switch B

Switch C

A1A2

A3

B1B2

B3

C1C2

C3

A switch is configured with four VLANs. Which is true? Each VLAN forms its own broadcast domain. Each VLAN is a separate subnet and needs its own subnet address. The Switch keeps a separate bridging table for each VLAN. All of the above.

Which VLAN is used for STP and CDP messages?

VLAN 1The management VLANThe native VLANThe data VLANAny VLAN you choose

Which is true of a static VLAN? VLAN membership depends on the MAC address of the workstation. VLAN membership depends on the IP address of the workstation. VLAN membership depends on the Switch port to which the

workstation is connected. It is not possible to change the VLAN membership once it has been

configured. Static VLANs require the use of special software packages such as

CiscoWorks 2000.

Which is true of a dynamic VLAN? VLAN membership depends on the MAC address of the

workstation. VLAN membership depends on the Switch port to which the

workstation is connected. It is not possible to change the VLAN membership once it has been

configured. Dynamic VLANs have become common since the introduction of

DHCP.

You have configured static VLANs on a switch. The marketing department uses VLAN 4. A member of the marketing department moves to a different office, taking her PC with her. What needs to be done?

Nothing. The PC will be recognised in its new position and will stay on VLAN 4.

The cabling must be altered so that the PC is still connected to one of the Switch ports on VLAN 4.

The Switch configuration must be altered so that the port connected to the PC is reassigned to VLAN 4.

The VLAN must be changed to a dynamic VLAN.

A switch has static VLANs configured. Three workstations are connected to the same Switch port by using a hub. What is the effect of this?

The three workstations must be on the same VLAN. The hub must be configured with the same static VLANs as the Switch.


The Switch must be configured with sub interfaces if the workstations are on different VLANs.

It is not possible for workstations to share a Switch port when VLANs are used.

The marketing department is on VLAN 4 and the sales department is on VLAN 5. How can a member of the marketing department communicate with a member of the sales department?

The Switch will detect that the destination is on a different segment and flood packets through all ports

The Switch needs to be configured to pass packets between different VLANs.

The packets must be sent via an enterprise server. A router is needed to route packets between different VLANs.

1A new switch has the default configuration. Which of the following are true? (Choose two)

VLAN 1 exists, and all ethernet ports are assigned to it. Each group of eight ports is assigned to a different VLAN. An IP address is assigned to VLAN 1. There may be default VLANs for different LAN technologies, such

as token Ring and FDDI.

An administrator wants to configure an IP address on a switch so that the switch can be configured remotely. What should the administrator do?

Configure the IP address on port 0/1. Configure the IP address on all ports. Configure the IP address on the management VLAN. Configure the IP address on all VLANs. You cannot configure an IP address on a switch.

1Where is frame tagging necessary to identify VLAN membership? Between the source workstation and the nearest switch. Between switches if a link carries frames belonging to more than

one VLAN. Between switches if a link carries frames belonging to only one VLAN. Between the switch and the destination workstation.

Which statements are true of IEEE 802.1Q frame tagging? (Choose two) It is a Cisco proprietary encapsulation protocol. It inserts a VLAN identifier and other fields into the frame header. It encapsulates the frame with an additional header. It is now the preferred method for identifying VLAN traffic between

switches. It used to be the most common method for identifying VLAN traffic

between switches, but it is not in common use any more.

Where is frame tagging added to the frame? At the source host workstation.


At the destination host workstation. At a switch, before the frame is placed on a trunk connection. At a switch, after the frame is received from a trunk connection.

Where is frame tagging removed from the frame? At the source host workstation. At the destination host workstation. At a switch, before the frame is placed on a trunk connection. At a switch, after the frame is received from a trunk connection.

Which commands would you use in order to create a VLAN number 4, called Marketing?

Switch# vlan 4Switch(vlan)#name Marketing

Switch(config)# vlan 4Switch(config-vlan)#name Marketing

Switch(config)#vlan accessSwitch(config)#vlan 4 name Marketing

Switch(vlan)#vlan 4 Switch(vlan)#name Marketing

Switch(config)#vlan 4 Marketing

Which commands would you use in order to assign the fast ethernet port 0/7 to VLAN 4? (Choose three)

Switch(vlan)# interface fastethernet 0/7 Switch(config)#interface fastethernet 0/7 Switch(config-if)#switchport mode access Switch(vlan-if)#switchport access vlan 4 Switch(config-if)#switchport access vlan 4 Switch(config-if)#switchport vlan 4 Switch(config)#interface fastethernet 0/7 vlan 4 Switch(config-if)#switchport mode access vlan 4

Ports 0/7, 0/8 and 0/9 all belong to VLAN 4. You give the commandsSwitch(config)#interface fastethernet 0/9Switch(config-if)# no switchport access vlan 4 Which of the following statements is true?

VLAN 4 has been deleted. All three ports have been removed from VLAN 4. Port 0/9 is now inactive and needs to be assigned to a new VLAN. Port 0/9 is reassigned to VLAN 1.

Ports 0/7, 0/8 and 0/9 all belong to VLAN 4. You give the commandSwitch(config)# no vlan 4 Which of the following statements are true? (Choose 2)

VLAN 4 has been deleted. All three ports have been assigned to VLAN 1. VLAN 4 still exists but the ports are no longer assigned to it. All three ports are inactive and not assigned to any VLAN. All three ports will be reassigned to VLAN 1 when the Switch is reset.


Which command would you give to view the contents of the VLAN database? Switch#show vlan Switch#show vlan database Switch#(vlan)show vlan Switch#(vlan)show vlan database Switch#show database vlan

If you do not specify which VLANs are allowed on a trunk link, what will happen?

No VLANs can send traffic over the link. Only VLAN 1 can send traffic over the link. Only the management VLAN can send traffic over the link. All VLANs can send traffic over the link.

Which is true about VLAN information?

You should save the running configuration so that VLAN information is held in the startup configuration.

VLAN information is held in the VLAN database in flash memory. You can remove VLAN information by giving the erase start command

and reloading. VLAN information is not saved, but is re-learned from neighbouring

switches on start-up by using CDP.

IEEE 802.1q and ISL are:

Different encapsulation methods for tagging frames on trunk links.

Both supported on all Cisco Catalyst switches. Different methods of assigning devices to VLANs. Different methods of sharing VLAN information between switches.


A switch port has been configured as follows:

SW1(config)#int fa 0/12SW1(config-if)#mls qos trust cosSW1(config-if)#switchport voice vlan 150SW1(config-if)#switchport mode accessSW1(config-if)#switchport access vlan 5SW1(config-if)#end

Which is true?

There is a conflict because the port has been configured on two VLANs.

The port is on VLAN 5 only, because the later configuration replaces the earlier configuration.

The port can handle both voice and data traffic. The port will give priority to traffic on VLAN 5.



What is the default Catalyst switch configuration?

VTP version 1, Mode server, Domain name cisco1, revision number 1. VTP version 1, Mode server, no Domain name, revision number 0. VTP version 2, Mode server, no Domain name, revision number 0. VTP version 1, Mode client, Domain name cisco1, revision number 0.

Which switches can only use VTP version 1, and not version 2?

Catalyst 2960 switches All Catalyst switches Older Cisco switches Non-Cisco switches

If you have a domain of switches that are all capable of using version 2, and you want them to use version 2, which switches must you configure for version 2?

All switches All server switches Any server switch Any switch

You have a group of switches that have never been configured for VTP, and you want them to act as a VTP domain. What is the best way of ensuring that they all have the same domain name?

Configure the name on one switch that is in server mode and allow the name to propagate to the other switches.

Configure the name on one switch, copy the name, and paste it to the other switches.

Configure the name on one switch, copy the configuration to a TFTP server, and download it to the other switches.

It does not matter whether they have the same domain name or not as long as they are using the same version and the same password.

Why should you configure a domain name on a server switch before creating the VLANs that you want to share with the domain?

VLANs cannot be created on a switch until the domain name is configured.

Existing VLANs (except the default VLAN) are deleted when you configure a domain name.

VLANs created before the domain name is configured will be local to the switch.

You need to create VLANs in VTP configuration mode.


Which is true about the switches in the diagram?

S1 must be in the same VTP domain as S4 S8 must be in the same VTP domain as S9 S2 cannot be in the same VTP domain as S6 S4 cannot be in the same VTP domain as S7

All the switches have the same VTP domain name. S1 has been configured as a server. Which is true?

All the other switches in the domain must be configured as either client or transparent.

S4 should not be transparent as this will cut S5 and S6 off from the rest of the domain.

S4, S5 and S6 can form their own domain as well as belonging to the same domain as S1.

S5 may be a server switch in the same domain as S1.

Which is true of VTP?

It operates at OSI layer 1 It operates only on Cisco switches A VTP domain can extend beyond a layer 3 switch VTP is enabled by default on Catalyst switches

Which of these is not the name of a VTP advertisement?

Summary advertisement Request advertisement Detail advertisement Subset advertisement

How is a VTP advertisement encapsulated?


In the data field of an IP packet In the data field of an Ethernet frame In a set of extra fields added to the frame header As part of the tag of a tagged Ethernet frame

What does a VTP server switch do if it receives a VTP subset advertisement with a higher revision number than its existing revision number?

It ignores the advertisement because only client switches update their VLAN information from advertisements.

It increases the revision number by 1 and passes the advertisement on to other switches in the domain.

It updates its own VLAN configuration by using the information in the advertisement.

It updates its own revision number but does not use the information contained in the advertisement.

What can you not do on a VTP client switch?

Configure the VTP domain name Delete a VLAN Assign a switchport to a VLAN Set a password

In the diagram, switches S1, S2, S3, S5 and S6 all have switchports on VLANs 10, 20 and 30. Switch S4 does not use any of these VLANs. Switch S4 has switchports on VLANs 40 and 50, which are not used elsewhere. How should S4 be configured?

S4 should be put in transparent mode. S4 should be a server, and have a different domain name from the

other switches. S4 should have its revision number reset to zero. S4 should have a different password from the other switches.

How many server switches should you have in a VTP domain?

Only one.


It is a good idea to have two, so that there is a back up for the data, but there cannot be more than two.

Up to half the switches can be servers. At least two, but it is possible for them all to be servers.

What happens when a client switch is reloaded?

It loses all its VLAN data and has to be reconfigured. It loses all its VLAN data and has to learn them again from a

server. It can retrieve its VLANs from NVRAM providing that the configuration

has been saved. It returns to the default server mode.

Where can VTP advertisements be sent?

On any links connecting switches. Only on trunk links. Only on links using 802.1Q frame tagging Only on links using ISL frame tagging

The switches have ports assigned to the VLANs shown. What is the best way of restricting VLAN 4 broadcast transmissions in order to cut down unnecessary traffic?

Enable VTP pruning on the switches. Add a router between S1 and S4. Have two separate VTP domains, one for S1, S2 and S3 and the other

for S4, S5 and S6. Make S1 into a transparent mode switch.

What triggers a VTP server switch to send a summary advertisement? Choose all that apply.

A 5 minute timer expires. A new VLAN has just been configured on the switch. An existing VLAN has just had its name changed. A Switchport had just been moved from one VLAN to another.


VLANs 2,3,4

VLANs 2,3,4

VLANs 2,3,4

VLANs 2,3

VLANs 2,3

VLANs 2,3

The switches are not exchanging VLAN information correctly. What is the likely problem?

One of the switches is in the wrong mode. One of the switches does not have switchports in VLANs 2 or 3. The switches do not all have the same config revision number. The switches are not all in the same VTP domain.



1 Which of the following problems may occur in redundant switched network topologies? (Choose three)

Excessive collisions. Broadcast storms. Multiple frame transmission. Fault-tolerance. Single point of failure. MAC address database instability.

2 What is the purpose of the spanning tree algorithm? To create a redundant topology. To build correct MAC address tables. To create a loop-free topology. To find the shortest path to a network address. To remove a single point of failure.

3 How can a broadcast storm be ended? Disconnect one of the switches. Wait until the frames time out. Send an ICMP source quench message. Clear the MAC address tables of the switches.

4 What is a multiple frame transmission? A frame is sent to multiple hosts. Several frames are forwarded by the same switch. A host receives the same frame several times by different paths. A frame is received by multiple hosts.

5 What is a disadvantage of the spanning tree algorithm? It takes longer to converge than is desirable. It is difficult to configure on new switches. It only works on Cisco catalyst switches. It turns off some switch ports.

6 What is a proposed solution to get rid of this disadvantage? Build networks with no physical loops. Avoid sending broadcast messages. Use rapid spanning tree protocol. Use spanning tree protocol version two. Use the Dijkstra algorithm.

7 What is a feature of a tree topology? It has a connection to every node. Every link is a point-to-point link. It provides fault-tolerance. It contains no loops.


8 What information is contained in a bridge protocol data unit? Root BID, route path cost, sender BID, port ID Root BID, sender BID, default path, bandwidth Root BID, root path cost, root bridge, designated port Root bridge, root port, sender BID, designated port

9 How is a BID made up? The switch base MAC followed by a bridge priority, default 1. The switch base MAC followed by a bridge priority, default 32768. A bridge priority, default 1, followed by the switch base MAC. A bridge priority, default 32768, followed by the switch base MAC.

10 How do switches choose a root bridge? They choose the switch with the highest bridge priority. They choose the switch with the highest BID. They choose the switch with the lowest BID. They choose the switch nearest to the default gateway. They choose the switch nearest to the top of the tree structure.

11 What will exist when the spanning tree protocol has worked and the network has converged?

One root bridge per network, one root port on each bridge, one designated port on each bridge, all non-designated ports are blocked.

One root bridge per network, one root port per non root bridge, one designated port per segment, non-designated ports.

One root bridge per segment, one root port per non root bridge, one designated port per segment, non-designated ports.

One root bridge per network, one root port on each switch, one non-designated port on each segment, other ports are blocked.

12 What is the default interval in seconds for sending bridge protocol data units?

1 2 5 10 30

13 What states does a port go through from the time when a switch first start up to the time when the port is fully operational?

Blocking, listening, learning, forwarding Disabled, listening, learning, forwarding Listening, learning, blocking, forwarding Blocking, learning, listening, forwarding Learning, listening, switching, forwarding

14 Which of the following does a port do in the listening state? (Choose all that apply.)

Learning MAC addresses. Forwarding user data.


Receiving BPDUs Sending BPDUs

15 Which of the following does a port do in the blocking state? (Choose all that apply.)

Learning MAC addresses. Forwarding user data. Receiving BPDUs Sending BPDUs None of the above

16 Which of the following does a port do in the learning state? (Choose all that apply.)

Learning MAC addresses. Forwarding user data. Receiving BPDUs Sending BPDUs

17 Which is the correct order of the stages carried out by the spanning tree protocol?

Select a designated port on each segment, select a root bridge, select a root port on each non-root bridge, block any remaining (non-designated) ports

Select a root port on each switch, select a root bridge, select a designated port on each segment, block any remaining (non-designated) ports.

Select a root bridge, select a designated port on each segment, select a root port on each non-root bridge, block any remaining (non-designated) ports

Select a root bridge, select a root port on each non-root bridge, select a designated port on each segment, block any remaining (non-designated) ports.

18 How long can it take for a network using spanning tree topology to converge again after a topology change?

up to 2 seconds up to 10 seconds up to 20 seconds up to 30 seconds up to 50 seconds up to 60 seconds

19 What will happen to user data frames while the network is converging? They will be discarded. They will be forwarded. They will be stored until the network has converged. They will collide.


20 Why might a network administrator change a switch priority to a higher value than that of other switches in the network?

To make sure that the switch is chosen as the root bridge. To make sure that the switch is not chosen as the root bridge. To help the network converge more quickly. To make sure that no ports on the switch are blocked. To make sure that switch MAC addresses are not used in choosing the

root bridge.

21 In rapid spanning tree protocol, which link types allow ports to move immediately to forwarding mode?

Point-to-point End to end Shared Multiple Edge type Mixed

22 It can take 20 seconds for a port to move from the blocking to the listening state. What timer controls this interval?

Blocking timer Listening timer Spanning tree timer Bridge protocol data unit timer Max-age timer

23 What is the listening forward delay? The time a port spends in listening mode while the network is

converging. The time a port spends forwarding mode while the network is

converging. The time a port spends before it reaches listening mode while the

network is converging. The time a port spends in listening to a frame before it forwards it.


24 The server wants to send a message to IP address 192.168.7.5 but it does not know the MAC address of that host. It sends an ARP request. What will switch A do with the ARP request?

Forward it to 192.1687.5. Forward it to Switch B Forward it through all ports Forward it through all ports except the port on which it was received Drop it

25 What is the likely effect on the topology shown if Spanning Tree Protocol has been disabled?

Excessive collisions Broadcast storm All hosts will reply to the ARP request The router will reply to the ARP request The segment 2 port on Switch B will go into blocking mode

26 What is the advantage of configuring an access port leading to a PC with PortFast?

The STP timers are changed so that the port moves through listening and learning states more quickly.

The port is secured so that no other PC can be connected to it. The port will be in the forwarding state as soon as it is enabled. RSTP will be in use on the switch.

27 Which STP port states are equivalent to the RSTP discarding port state?

Blocking, listening and learning Listening, learning and forwarding Listening. Learning and disabled Blocking, listening and disabled


28 Which is true of the difference between STP and RSTP?

STP uses a proposal and agreement process to allow switches to negotiate on port roles, but RSTP assigns the roles centrally.

STP stops sending user data while the whole network converges, but RSTP closes down and converges each link separately.

RSTP is able to support VLANs by using Cisco proprietary enhancements but STP is not.

RSTP is the default version on all Cisco switches now, but STP was the default until IOS version 11.4

29 How many switches in a network must be running STP or RSTP in order to avoid broadcast storms?

At least one. At least one in each loop. At least the switch that is chosen as the root bridge. All of them.

30 Which is true of a switch that has spanning tree disabled?

It will forward all frames in the normal way, and this includes BPDUs, though it does not originate BPDUs.

It cannot be chosen as the root bridge, and any of its ports that are involved in loops will be blocked.

If it is in a loop then a broadcast storm is inevitable. It cannot have any VLAN trunk links.

31 Which is true of the PVST+ protocol?

It is Cisco’s implementation of Rapid STP. It allows different VLANs to have different root bridges and allows ports

to be blocked for some VLANs but not others. It supports the use of VLANs and requires that ISL frame tagging

should be used on VLAN trunk links. It was the first version of STP to include the PortFast feature that

allows access ports to transition directly to the forwarding state.


32 Why was the BID modified to include an extra field, and what information is in this field?

To allow separate instances of STP to run for each VLAN. The field contains the VLAN number (VID).

To allow rapid spanning tree protocol to be introduced. The field contains the value 2.

To allow the PortFast feature to be introduced. The field shows which ports have been configured as PortFast.

To allow ports to have priorities as well as the switch as a whole having a priority. The field contains a summary of port priorities.

33 How many missed BPDUs will indicate to a switch running RSTP that a link has gone down?

1 3 10 30

34 If a port is configured as a RSTP edge port, what will cause it to revert to a normal spanning tree port?

It needs to be manually reconfigured as it cannot revert automatically. It will revert to a normal spanning tree port if a link in the network goes

down. It will revert to a normal spanning tree port if it receives a BPDU. It will revert to a normal spanning tree port if a new election for root

bridge is required.

35 In RSTP, a port other than an edge port can transition rapidly to forwarding state if it is on which type of link?

Point-to-point Point-to-multipoint Shared Edge-to-edge



What is the problem with the network in the diagram?

It is not possible for a router to have four FastEthernet ports. The VLANs will not be able to communicate with each other. The router is not needed because these VLANs can communicate

through the switch. This design will not scale well if more VLANs are added.

Another VLAN is added to the network shown above, but the router does not have a spare FastEthernet port. What would be the most economical solution?

Buy an extra module for the router to provide more FastEthernet ports. Connect an extra router, link the two routers together and enable a

routing protocol between them. Configure a trunk link on the switch and subinterfaces on one of

the router ports. Use a cheap hub to connect all the VLANs to the same router interface.

A trunk link between a router and a switch is carrying traffic for six VLANs. What is a potential problem?

The VLANs are sharing the link’s bandwidth and this could create a bottleneck.

The volume of VTP traffic on the link is likely to have an adverse effect on the network’s performance.

The traffic for the different VLANs is likely to be confused as all the traffic goes through the same physical router interface.

The maximum number of subinterfaces that can be configured on a router port is five.

A switch is configured as follows:


SW(config)#int f0/1SW(config-if)#switchport mode access SW(config-if)#switchport access VLAN 3SW(config-if)#description link to router f0/0SW(config)#int f0/2SW(config-if)#switchport mode access SW(config-if)#switchport access VLAN 3SW(config-if)#description link to router f0/1SW(config)#int f0/3SW(config-if)#switchport mode access SW(config-if)#switchport access VLAN 3SW(config-if)#description link to PC ASW(config)#int f0/4SW(config-if)#switchport mode access SW(config-if)#switchport access VLAN 4SW(config-if)#description link to PC B

Why is PC A unable to ping PC B?

There needs to be a trunk link to the router in order for VLANs to communicate with each other.

The no shutdown command has not been given on the switch interfaces.

The router will not handle traffic to or from VLAN 4. Interface f0/1 on the switch should be connected to interface f0/1 on

the router.

A router is to be added to the configuration shown in the diagram above. This will allow communication between the different VLANs. How many fast ethernet ports will the router need?

None, serial ports must be used. One, since trunking can be used. Two, one connecting to each switch. Three, one for each VLAN. Six, one for each VLAN on each switch.

How many IP addresses must be configured on the router mentioned in the previous question?

None, because VLANs operate at layer two. One, because only one physical ports is needed.


Two, one for each switch. Three, one for each VLAN. Six, one for each VLAN on each switch.

Switchport 0/4 is on VLAN2, port 0/6 is on VLAN3, port 0/8 is on VLAN4.Part of the router configuration is as follows:Router(config)#interface fastethernet 0/1.2Router(config-subif)#encapsulation dot1q 2Router(config-subif)#ip address 192.168.1.0 255.255.255.240Router(config)#interface fastethernet 0/1.3Router(config-subif)#encapsulation dot1q 3Router(config-subif)#ip address 192.168.1.33 255.255.255.240Router(config-subif)# interface fastethernet 0/1.4Router(config-subif)# encapsulation dot1q 4Router(config-subif)#ip address 192.168.1.49 255.255.255.240

Which of the following host IP addresses are suitable? (Choose 2)

Host A, 192.168.1.20 Host A, 192.168.1.32 Host B, 192.168.1.46 Host B, 192.168.1.47 Host C, 192.168.1.44 Host C, 192.168.1.60

Topology and configuration are the same as in the previous question. Host IP addresses are set as follows:Host A, 192.168.1.13Host B, 192.168.1.50Host C, 192.168.1.58Which statements are true? (Choose all that apply)

Host A can receive messages from host B Host A can receive messages from host C Host B can receive messages from host A Host C can receive messages from host A


A router-on-a-stick is configured as follows:R(config)#interface f0/1.2R(config-subif)#encapsulation dot1q 20R(config-subif)#ip add 172.18.0.1 255.255.255.128R(config-subif)#interface f0/1.3R(config-subif)#encapsulation dot1q 30R(config-subif)#ip add 172.18.0.161 255.255.255.224R(config-subif)#interface f0/1.4R(config-subif)#encapsulation dot1q 40R(config-subif)#ip add 172.18.0.193 255.255.255.224R(config-subif)# interface f0/1R(config-if)#no shutdown

The router receives a frame on physical interface f0/1. The destination IP address is 172.18.0.120. What will the router do?

Drop the frame because the IP address is not on a known network. Send the frame out of interface f0/2. Send the frame out of interface f0/1.2 tagged for VLAN 2. Send the frame out of interface f0/1.2 tagged for VLAN 20.

Which is true of inter-VLAN routing using “router-on-a-stick”?

Not every router is able to create subinterfaces for VLANs. It depends on the IOS features.

It is possible if the switch uses IEE802.1Q tagging, but not if the switch uses ISL.

The router has to be running a routing protocol that supports VLSM. The configuration is simpler than if separate physical interfaces are

used, but the cabling is more complicated.

How are default gateways configured for inter-VLAN routing when “router-on-a-stick” is used?

All PCs attached to the switch will share the same default gateway since there is only one physical connection to the router.

PCs on different VLANs must be configured with different default gateways.

PCs must be configured with the same default gateway as the switch. The switch default gateway is the IP address of the physical interface

on the router.


What is true about MAC addresses when “router-on-a-stick” is used for inter-VLAN routing?

Each subinterface on the router has its own MAC address. Each default gateway at layer 3 is linked with a different MAC address

at layer 2. Each physical Ethernet interface on the router has one MAC

address. The MAC address of the router interface is not used when the interface

is configured for trunking.



Which statements are true of the Bluetooth 802.15.3 standard? (Choose 2)

It is used for peer-to-peer devices that are close to each other. It is used for medium sized LANs. It is used for mobile devices that communicate with a satellite. It operates with a speed of less than 1 Mbps. It operates with a speed of 1 - 10 Mbps. It operates with a sped of 10 - 100 Mbps.

Which statements are true of the 802.11 standard? (Choose 2)

It is used for peer-to-peer devices that are close to each other. It is used for medium sized LANs. It is used for mobile devices that communicate with a satellite. It operates with a speed of less than 1 Mbps. It operates with a speed of 1 - 10 Mbps. It operates with a speed of 10 - 100 Mbps.

In which wave band does 802.11g operate?

1.3 GHz 2.4 GHz 5.7 GHz 10 GHz

What was an advantage of 802.11b over 802.11a?

802.11b was faster than 802.11a. 802.11b was less prone to interference than 802.11a. 802.11b was cheaper than 802.11a. 802.11b operated over a longer distance than 802.11a.

Which statements are true of 802.11g? (Choose all that apply.)

It operates in the same wave band as 802.11a. It operates in the same wave band as 802.11b. Operating speed is faster than 802.11b. Operating speed is slower than 802.11b. It is compatible with 802.11a but not 802.11b. It is compatible with 802.11b but not 802.11a.

Why do wireless NICs not detect collisions?


Collisions do not occur with wireless communication because there is no shared medium.

Access points behave like switches and provide dedicated bandwidth to each device.

Communication between wireless NICs and access points is full duplex.

It would be too expensive to make wireless NICs that are capable of detecting collisions.

Why is access to the wireless medium regarded as distributed?

It is the responsibility of all devices to detect RF signals and wait until the medium is free before transmitting.

The access point receives signals from devices that are distributed around it.

Signals are distributed over the wave band. The access point controls the allocation of the shared medium to the

wireless devices.

If wireless devices are on opposite sides of the access point and are too far apart to sense each other, the hidden node problem occurs. What is this problem?

The devices will not receive acknowledgement of their transmissions and will therefore assume that the message was lost and send it again.

The two devices will be unable to communicate with each other. One device may transmit while the other is transmitting, resulting

in a collision. Structural features of the building are likely to interfere with signals.

Which device does a Cisco wireless access point most resemble in its behaviour?

An Ethernet hub An Ethernet layer 2 switch An Ethernet layer 3 switch A router

How does RTS/CTS resolve the hidden node problem?

It strengthens the signals so that devices on opposite sides of the access point are able to sense each other.

The access point allocates the medium to one device, on request, for as long as it needs to transmit.

It allows transmissions to be repeated when there is a collision. Devices take turns to transmit, and can do so when they hold the

token.


Which device typically combines the roles of wireless access point, Ethernet switch, and router?

Modem Layer 3 switch Wireless router Wireless NIC

A single access point and the devices connected to it are known as:

A BSS An ESS An ESA An ad hoc topology

What is the effect of RF signal attenuation?

It causes interference. It causes collisions. It limits the area covered by an access point. It limits the number of access points in an ESS.

What name is commonly given to people who look for unsecured wireless networks and use them to gain Internet access?

Hackers Crackers Surfers War drivers

An access point is using channel 1. Another access point must be added on the same network to extend the area covered. What channel should this additional access point use in order to avoid performance problems?

Channel 1. Channel 2 or higher number. Channel 4 or higher number. Channel 6 or higher number.

How far should an access point be from the nearest person?

At least 10 cm At least 20 cm At least 50 cm At least 1 m

How far should an access point be from metal objects?


At least 1 foot At least 2 feet At least 3 feet At least 4 feet

How should an access point be mounted?

Horizontally Vertically At an angle of 45 degrees At the same height as the wireless devices

What is CSMA/CA?

A method used to detect collisions on wireless networks and allow devices to resend messages that have been lost after waiting for a random length of time.

A system for avoiding collisions by making devices wait until they hold a token before they are allowed to transmit.

A system for avoiding collisions by making devices check if the medium if free before transmitting, then using acknowledgements to confirm that the message was received.

A method used so that wireless devices can connect to a wired Ethernet network without causing collisions on the wired network.

Which is true of an extended service set, where several access points with overlapping coverage areas are deployed on a network?

The overlap in coverage must not be more than 5% otherwise there will be interference and poor performance.

The access points should use the same SSID so that mobile devices can roam from one area to another.

The access points should use different SSIDs for security purposes. The access points must use different RF wave bands.

How many methods of authentication are specified in the 802.11 standard?

None. One: open authentication. Two: open authentication and shared key. Three: open authentication, shared key and TKIP. Four: open authentication, shared key, TKIP and AES.

Where possible, wireless networks should use security that follows the 802.11i standard. This is equivalent to:


TKIP WEP WPA WPA2

When is it sensible to set up open access on the access point?

When SSID broadcasts are turned off. On a home network. When security is based on checking MAC addresses. While a new wireless network is being set up.

Which statements are true of the SSID? (Choose 2)

It identifies a particular wireless network. It identifies a specific access point. For security reasons, the default value should not be used. Turning off SSID broadcasts will ensure network security.

A rogue access point can compromise network security. Which is an example of a rogue access point?

An employee connects his own access point in order to use his wireless laptop in his office.

A technician installs an access point with a channel that overlaps with an existing access point.

An access point is installed on an outside wall so that its range extends well outside the building.

An access point is configured to broadcast SSIDs, whereas the other access points on the network do not.

What are the effects of modifying a wireless NIC so that it accepts all traffic and not just traffic destined for its own MAC address? (Choose 2)

The NIC will behave like an access point. The NIC can be used to carry out a “man in the middle” security

attack. The NIC will transmit simultaneously with the original access point and

cause collisions. The NIC will be overloaded and disassociate itself.


How could an attacker who has modified his laptop’s wireless NIC mount a denial of service attack? (Choose 2)

Send repeated CTS (clear to send) messages, so that devices transmit simultaneously and cause collisions.

Send transmissions on a different channel so that other devices do not detect them.

Send repeated disassociate commands so that devices disassociate and then generate traffic as they try to reassociate.

Change the password for authentication so that devices are locked out of the network.

Why do some people choose to leave SSID broadcasts enabled rather than disabling them?

It allows mobile devices to move from one access point to another within the network, otherwise they would need to be reconfigured.

Hackers can detect SSIDs relatively easily, so disabling SSID broadcasts is not regarded as an effective security measure.

New devices cannot detect an access point if SSID broadcasts are disabled.

Disabling SSID broadcasts prevents a network from having several access points operating simultaneously.

In which order does a wireless device carry out procedures for connecting to a wireless network?

Associate, Probe, Authenticate Authenticate, probe, Associate Probe, Authenticate, Associate Probe, Associate, Authenticate

How should you set the channel on your access point for best performance? (Choose 2)

Wide channel (40MHz) if you have Wireless-G, Wireless-B and Wireless-N devices.

Wide channel (40MHz) if the mode is Wireless-N only. Standard channel if the mode is Wireless-G only. Auto if the mode setting is Disabled.


Which statements are true of a RADIUS server? (Choose 2)

802.11i includes the optional use of a RADIUS server for authentication.

802.11i specifies that a RADIUS server must be used for security. The RADIUS option that is available for a Linksys wireless router

allows you to use a RADIUS server in combination with WEP. Each access point contains its own RADIUS server software, a central

AAA server is not needed.

The process of broadcasting a network’s SSID is called:

Probing Associating Beaconing Advertising

Which statements are true of TKIP? (Choose 2)

TKIP uses a different encryption key for each packet. TKIP uses the same encryption algorithm as WEP. TKIP failed to address the weaknesses of WEP security. TKIP complies with broader IT industry standards and particularly IEEE

802.11i.


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