Networking Devices and Initial Configuration Course Final Exam Answers

1. Match the definition to the type of cloud.

Explanation: Place the options in the following order:

intended for exclusive use by multiple organizations with shared functional needs	community
services made available to the general population	public cloud
made up of two or more distinct cloud infrastructures bound together by technology	hybrid cloud
intended for a specific organization or entity, such as the government	private cloud

2. A data center has recently updated a physical server to host multiple operating systems on a single CPU. The data center can now provide each customer with a separate web server without having to allocate an actual discrete server for each customer. What is the networking trend that is being implemented by the data center in this situation?

maintaining communication integrity
online collaboration
virtualization
BYOD

Explanation: Virtualization technology can run several different operating systems in parallel on a single CPU.

3. What is an example of cloud computing?

a service that offers on-demand access to shared resources
a network infrastructure that spans a large geographic area
an architectural style of the World Wide Web
a continuous interaction between people, processes, data, and things

Explanation: Cloud computing provides on-demand access to shared resources. With minimal management effort, resources can be deployed quickly at data centers.

4. Which two scenarios would benefit the user the most by adding quality of service (QoS) to the network? (Choose two.)

Students are updating information about their sport activities on the class Facebook page.
A student is sending emails to a friend.
A student is communicating via Skype with a friend in another country.
Students are watching a lecture from a YouTube site.

Explanation: Voice and video data need to be transmitted in a continuous stream. If packets are delayed, the audio and video quality will be poor, sometimes even not usable. QoS can give voice and video data high priority during the data transmission so that they would be sent first before other types of traffic, such as email, web surfing, and web page update.

5. An employee of a large corporation remotely logs into the company using the appropriate username and password. The employee is attending an important video conference with a customer concerning a large sale. It is important for the video quality to be excellent during the meeting. The employee is unaware that after a successful login, the connection to the company ISP failed. The secondary connection, however, activated within seconds. The disruption was not noticed by the employee or other employees.
What three network characteristics are described in this scenario? (Choose three.)

scalability
security
integrity
fault tolerance
quality of service
powerline networking

Explanation: Usernames and passwords relate to network security. Good quality video, to support video conferencing, relates to prioritizing the video traffic with quality of service (QoS). The fact that a connection to an ISP failed and was then restored but went unnoticed by employees relates to the fault tolerant design of the network.

6. Which three statements describe the functions of the Cisco hierarchical network design model? (Choose three.)

The goal of the core layer is maximizing throughput.
The distribution layer distributes network traffic directly to end users.
The distribution layer is responsible for traffic filtering and isolating failures from the core.
The access layer provides a means of connecting end devices to the network.
Route summarization is not necessary at the core and distribution layers.
The core layer usually employs a star topology.

Explanation: There are three layers of the hierarchical network design model.
– Access: Provides a connection point to end users.
– Distribution: Controls traffic flows between access and core layers.
– Core: Maximizes throughput moving traffic as quickly as possible.

7. What is the key difference between a type 1 hypervisor and a type 2 hypervisor?

A type 1 hypervisor runs directly on the system hardware and a type 2 hypervisor requires a host OS to run.
A type 1 hypervisor supports server virtualizations and a type 2 hypervisor only supports workstation virtualization.
A type 1 hypervisor supports all server OS virtualization and a type 2 hypervisor supports Linux and Mac virtualization.
A type 1 hypervisor runs on specialized systems and a type 2 hypervisor runs on desktop computers.

Explanation: There are two types of hypervisors:
– Type 1 – This type of hypervisor runs directly on the system hardware.
– Type 2 – This type of hypervisor requires a host OS to run.
Both types of hypervisors can run on regular computer systems and support multiple OS virtualizations.

8. Refer to the exhibit. Host A has sent a packet to host B. What will be the source MAC and IP addresses on the packet when it arrives at host B?
Networking Devices and Initial Configuration Course Final Exam 8

Source MAC: 00E0.FE91.7799
Source IP: 10.1.1.10

Source MAC: 00E0.FE91.7799
Source IP: 10.1.1.1

Source MAC: 00E0.FE10.17A3
Source IP: 10.1.1.10

Source MAC: 00E0.FE91.7799
Source IP: 192.168.1.1

Source MAC: 00E0.FE10.17A3
Source IP: 192.168.1.1

Explanation: As a packet traverses the network, the Layer 2 addresses will change at every hop as the packet is de-encapsulated and re-encapsulated, but the Layer 3 addresses will remain the same.

9. Which two statements are correct in a comparison of IPv4 and IPv6 packet headers? (Choose two.)

The Time-to-Live field from IPv4 has been replaced by the Hop Limit field in IPv6.
The Version field from IPv4 is not kept in IPv6.
The Destination Address field is new in IPv6.
The Source Address field name from IPv4 is kept in IPv6.
The Header Checksum field name from IPv4 is kept in IPv6.

Explanation: The IPv6 packet header fields are as follows: Version, Traffic Class, Flow Label, Payload Length, Next Header, Hop Limit, Source Address, and Destination Address. The IPv4 packet header fields include the following: Version, Differentiated Services, Time-to-Live, Protocol, Source IP Address, and Destination IP Address. Both versions have a 4-bit Version field. Both versions have a Source (IP) Address field. IPv4 addresses are 32 bits; IPv6 addresses are 128 bits. The Time-to-Live or TTL field in IPv4 is now called Hop Limit in IPv6, but this field serves the same purpose in both versions. The value in this 8-bit field decrements each time a packet passes through any router. When this value is 0, the packet is discarded and is not forwarded to any other router.

10. Match the IPv6 packet header field with the description.

Explanation: Place the options in the following order:

Traffic Class	8 bit field that is equivalent to the IPv4 Differenciated Services (DS) field.
Next Header	8 bit field that indicates the data payload type.
Flow Label	20 bit field that maintains the same packet flows through routers and switches to ensure that the packets arrive in the same order.
Payload Length	16 bit field that stipulates the length of the data portion of the IPv6 packet.
Hop Limit	8 bit field that is decremented by one for each router that fowards the packet.

11. Which three IPv4 header fields have no equivalent in an IPv6 header? (Choose three.)

protocol
fragment offset
TTL
version
identification
flag

Explanation: Unlike IPv4, IPv6 routers do not perform fragmentation. Therefore, all three fields supporting fragmentation in the IPv4 header are removed and have no equivalent in the IPv6 header. These three fields are fragment offset, flag, and identification. IPv6 does support host packet fragmentation through the use of extension headers, which are not part of the IPv6 header.

12. Refer to the exhibit. A ping to PC2 is issued from PC0, PC1, and PC3 in this exact order. Which MAC addresses will be contained in the S1 MAC address table that is associated with the Fa0/1 port?

Networking Devices and Initial Configuration Course Final Exam 12

just the PC1 MAC address
just PC0 and PC1 MAC addresses
just the PC0 MAC address
PC0, PC1, and PC2 MAC addresses
just the PC2 MAC address

Explanation: Switch S1 builds a MAC address table based on the source MAC address in the frame and the port upon which the frame enters the switch. The PC2 MAC address will be associated with port FA0/2. Because port FA0/1 of switch S1 connects with another switch, port FA0/1 will receive frames from multiple different devices. The MAC address table on switch S1 will therefore contain MAC addresses associated with each of the sending PCs.

13. Match field names to the IP header where they would be found.

Explanation: Options matched to the correct selection.

IP v4 header	IP v6 header
Flags	Traffic Class
Total Length	Flow Label

14. What is the dotted decimal representation of the IPv4 address
11001011.00000000.01110001.11010011?

203.0.113.211
209.165.201.223
198.51.100.201
192.0.2.199

Explanation: Each section (octet) contains eight binary digits. Each digit represents a specific value (128, 64, 32, 16, 8, 4, 2, and 1). Everywhere there is a 1, the specific value is relevant. Add all relevant values in a particular octet to obtain the decimal value. For example binary 11001011 equals 203 in decimal.

15. Which two items are used by a host device when performing an ANDing operation to determine if a destination address is on the same local network? (Choose two.)

network number
destination IP address
source MAC address
destination MAC address
subnet mask

Explanation: The result of ANDing any IP address with a subnet mask is a network number. If the source network number is the same as the destination network number, the data stays on the local network. If the destination network number is different, the packet is sent to the default gateway (the router that will send the packet onward toward the destination network).

16. A home network has both wired and wireless connectivity. From a laptop computer, the user issues a ping to the wireless printer located in another room. The first two echo requests fail, but the last two succeed. Additional pings are all successful. Why do the first two echo requests fail?

The computer and the printer must join the wireless network first and that process takes time.
The distance between the computer and the printer causes delay on the first two pings.
The wireless printer must be activated and that takes time.
The computer must use ARP to obtain the MAC address of the printer and this process takes time.

Explanation: In order to successfully send a packet on an Ethernet network, the computer sending the ping needs four key pieces of information: (1) source MAC address, (2) destination MAC address, (3) source IP address, and (4) destination IP address. The computer sending the ping knows its own source IP address and source MAC address. The computer also knows from the ping command the destination IP address. The only information not known is the destination MAC address. The destination MAC address is discovered by using ARP.

17. Which statement is true regarding the UDP client process during a session with a server?

A session must be established before datagrams can be exchanged.
Datagrams that arrive in a different order than that in which they were sent are not placed in order.
Application servers have to use port numbers above 1024 in order to be UDP capable.
A three-way handshake takes place before the transmission of data begins.

Explanation: Because there are no sequence numbers in UDP segments, there is no possibility to arrange the datagrams in the correct order. Sessions and three-way handshake are related to TCP communications. UDP servers can use registered or nonregistered port numbers to listen to clients.

18. Match each DHCP message type with its description.

Networking Devices and Initial Configuration Course Final Exam 18

Explanation: Place the options in the following order:

DHCPDISCOVER	a client initiating a message to find a DHCP server
DHCPOFFER	a DHCP server responding to the initial request by a client
DHCPREQUEST	the client accepting the IP address provided by the DHCP server
DHCPACK	the DHCP server confirming that the address lease has been accepted

19. Refer to the exhibit. Which protocol was responsible for building the table that is shown?
Networking Devices and Initial Configuration Course Final Exam 19

ARP
DHCP
ICMP
DNS

Explanation: The table that is shown corresponds to the output of the arp -a command, a command that is used on a Windows PC to display the ARP table.

20. Refer to the exhibit. A web designer calls to report that the web server web-s1.cisco.com is not reachable through a web browser. The technician uses command line utilities to verify the problem and to begin the troubleshooting process. Which two things can be determined about the problem? (Choose two.)
Networking Devices and Initial Configuration Course Final Exam 20

A router is down between the source host and the server web-s1.cisco.com.
The web server at 192.168.0.10 is reachable from the source host.
The default gateway between the source host and the server at 192.168.0.10 is down.
DNS cannot resolve the IP address for the server web-s1.cisco.com.
There is a problem with the web server software on web-s1.cisco.com.

Explanation: The successful result of the ping to the IP address indicates that the network is operational and the web server is online. However, the fact that the ping to the domain name of the server fails indicates there is a DNS issue, namely that the host cannot resolve the domain name to its associated IP address.

21. What are two potential network problems that can result from ARP operation? (Choose two.)

Multiple ARP replies result in the switch MAC address table containing entries that match the MAC addresses of hosts that are connected to the relevant switch port.
Network attackers could manipulate MAC address and IP address mappings in ARP messages with the intent of intercepting network traffic.
On large networks with low bandwidth, multiple ARP broadcasts could cause data communication delays.
Manually configuring static ARP associations could facilitate ARP poisoning or MAC address spoofing.
Large numbers of ARP request broadcasts could cause the host MAC address table to overflow and prevent the host from communicating on the network.

Explanation: Large numbers of ARP broadcast messages could cause momentary data communications delays. Network attackers could manipulate MAC address and IP address mappings in ARP messages with the intent to intercept network traffic. ARP requests and replies cause entries to be made into the ARP table, not the MAC address table. ARP table overflows are very unlikely. Manually configuring static ARP associations is a way to prevent, not facilitate, ARP poisoning and MAC address spoofing. Multiple ARP replies resulting in the switch MAC address table containing entries that match the MAC addresses of connected nodes and are associated with the relevant switch port are required for normal switch frame forwarding operations. It is not an ARP caused network problem.

22. Match the TCP flag to the correct step in the session establishment sequence.

Explanation: Place the options in the following order:

step 3	ACK
step 1	SYN
step 2	SYN + ACK

23. What is the difference between the terms keyword and argument in the IOS command structure?

A keyword is entered with a predefined length. An argument can be any length.
A keyword always appears directly after a command. An argument does not.
A keyword is required to complete a command. An argument is not.
A keyword is a specific parameter. An argument is not a predefined variable.

Explanation: Keywords are specific parameters that are defined in IOS. Arguments are not predefined; they are the variables defined by the user when completing a command. Although most keywords appear directly after commands, they can appear in other locations, depending on a command structure. A keyword can be entered in its whole length or in a shortened format.

24. Which three commands are used to set up secure access to a router through a connection to the console interface? (Choose three.)

line vty 0 4
password cisco
interface fastethernet 0/0
line console 0
enable secret cisco
login

Explanation: The three commands needed to password protect the console port are as follows:

– line console 0
– password cisco
– login

The interface fastethernet 0/0 command is commonly used to access the configuration mode used to apply specific parameters such as the IP address to the Fa0/0 port. The line vty 0 4 command is used to access the configuration mode for Telnet. The0and 4 parameters specify ports 0 through 4, or a maximum of five simultaneous Telnet connections. The enable secret command is used to apply a password used on the router to access the privileged mode.

25. What three configuration steps must be performed to implement SSH access to a router? (Choose three.)

a unique hostname
a password on the console line
an IP domain name
a user account
an enable mode password
an encrypted password

Explanation: To implement SSH on a router the following steps need to be performed:

– Configure a unique hostname.
– Configure the domain name of the network.
– Configure a user account to use AAA or local database for authentication.
– Generate RSA keys.
– Enable VTY SSH sessions.

26. Refer to the exhibit. What is the maximum TTL value that is used to reach the destination www.cisco.com?

Networking Devices and Initial Configuration Course Final Exam 26

Explanation: Traceroute (in this case the command tracert) sets the TTL field to a value of 1 and sends the packet. At each router hop, this value is decreased by one and a “TTL expired” message is sent back to the source host. This message has a source address which is used by the host to build the trace. The host then progressively increments the TTL field (2, 3, 4…) for each sequence of messages until the destination is reached or it is incremented to a predefined maximum. Because the executed command reached the destination in the 13th line, the TTL was increased up to the value of 13.

27. Which protocol is used by IPv4 and IPv6 to provide error messaging?

NDP
ARP
ICMP
DHCP

Explanation: ICMP is used by IPv4 and IPv6 to provide for messages to be sent in the event of certain errors and for informational purposes.

28. The global configuration command ip default-gateway 172.16.100.1 is applied to a switch. What is the effect of this command?

The switch can communicate with other hosts on the 172.16.100.0 network.
The switch can be remotely managed from a host on another network.
The switch will have a management interface with the address 172.16.100.1.
The switch is limited to sending and receiving frames to and from the gateway 172.16.100.1.

Explanation: A default gateway address is typically configured on all devices to allow them to communicate beyond just their local network.In a switch this is achieved using the command ip default-gateway <ip address>.

29. Match the router prompt to the configuration task.

Networking Devices and Initial Configuration Course Final Exam 29

Explanation: Place the options in the following order:

RouterA(config-line)#	configure vty lines
RouterA(config-if)#	configure a WAN interface
RouterA#	enter configuration mode
RouterA(config)#	add a password required to access the privileged EXEC mode

30. While troubleshooting a network problem, a network administrator issues the show version command on a router. What information can be found by using this command?

the amount of NVRAM, DRAM, and flash memory installed on the router
the bandwidth, encapsulation, and I/O statistics on the interfaces
differences between the backup configuration and the current running configuration
the version of the routing protocol that is running on the router

Explanation: The show version command displays much information about the device, including the amount of memory (flash, NVRAM, and DRAM) that is installed on the device.

31. Refer to the exhibit. PC1 sends a frame with the destination MAC address 3c97.0e07.a1b2. Switch S1 looks up the destination MAC address in its CAM table but the address is not there. What will the switch do?

It willl add the destination MAC address to the CAM table.
It will forward the frame out all ports except Fa0/1.
It will send a destination unreachable message back to PC1.
The switch will drop the frame.
It will forward the frame out port Fa0/2 towards the router.

Explanation: When a switch receives a frame with a destination that it does not already have in its CAM table, it will forward the frame out all ports except the one on which the frame was received. This is called unknown unicast flooding.

32. Which forwarding action does a switch take when the destination MAC address of an Ethernet frame is an unknown unicast?

The switch forwards the frame to the default gateway.
The switch forwards the frame the same way it does for broadcast and multicast MAC addresses.
The switch drops the frame.
The switch forwards the frame out a specified port for this type of address.

Explanation: If the destination MAC address is a unicast address, the switch will look for a match between the destination MAC address of the frame and an entry in its MAC address table:

If the destination MAC address is in the table, it will forward the frame out of the specified port.
If the destination MAC address is not in the table (unknown unicast), the switch will forward the frame out all ports except the incoming port. If the destination MAC address is a broadcast or a multicast, the frame is also flooded out all ports except the incoming port.

33. Refer to the exhibit. An administrator is troubleshooting connectivity on the office network. PC1 is able to send print jobs to Printer1, but is unable to access File Server1. Which action would correct the problem?

Change the R1 Fa0/1 interface IP address to 10.231.64.1.
Change the R1 Fa0/0 interface subnet mask to 255.255.0.0.
Change the File Server1 IP address to 10.231.96.253.
Change the PC1 IP address to 10.231.64.115.

Explanation: To correct the problem the Fa0/1 interface must be put into the 10.231.64.0 /19 network, so that it is in the same logical network as PC1. Currently the interface is in the 10.231.128.0 network.

34. Match the characteristic to the protocol category.

Explanation: Options matched to the correct selection.

TCP	UDP	Both UDP and TCP
window size	connectionless	checksum
3-way handshake	best for VoIP	port number

35. The ARP table in a switch maps which two types of address together?

Layer 3 address to a Layer 4 address
Layer 4 address to a Layer 2 address
Layer 2 address to a Layer 4 address
Layer 3 address to a Layer 2 address

Explanation: The switch ARP table keeps a mapping of Layer 2 MAC addresses to Layer 3 IP addresses. These mappings can be learned by the switch dynamically through ARP or statically through manual configuration.

36. A network administrator issues the Switch# show running-config command on a Cisco switch. Which term is used to describe the part “running-config” in the command?

command
argument
hot key
keyword

Explanation: The running-config is a keyword of the show command.

37. The global configuration command ip default-gateway 172.16.100.1 is applied to a switch. What is the effect of this command?

The switch can be remotely managed from a host on another network.
The switch can communicate with other hosts on the 172.16.100.0 network.
The switch will have a management interface with the address 172.16.100.1.
The switch is limited to sending and receiving frames to and from the gateway 172.16.100.1.

38. What is the purpose of the MAC address which is added to an e-mail message that is sent from a teacher to a student?

It identifies the network to which the sending computer belongs.
It identifies the computer on the Internet.
It identifies the TCP/IP network application to which the reply can be sent.
It identifies the computer on the LAN.

Explanation: A Media Access Control (MAC) address is unique on every device. An Internet Protocol (IP) address is used to communicate with devices on another LAN or on the Internet.

39. What is the purpose of assigning an IP address to the VLAN1 interface on a Cisco Layer 2 switch?

to enable remote access to the switch to manage it
to permit IP packets to be forwarded by the switch
to create a new IP local network on the switch
to enable the switch to route packets between networks

Explanation: The VLAN 1 on a Cisco Layer 2 switch is a virtual interface. By default, VLAN 1 is assigned as the management interface for remote access (Telnet or SSH) to the device for management tasks. In order to allow remote access through the network, a valid IP address configuration is needed on VLAN 1.

40. Which command should be used to test connectivity to the loopback interface?

ping 255.255.255.255
ping 0.0.0.0
ping 127.0.0.1
ping loopback

Explanation: The ping 127.0.0.1 command tests the TCP/IP stack through the loopback interface.