Test 1

Question 1

Which information is used by routers to forward a data packet toward its destination?

A) destination network IP address
B) destination gateway IP address
C) destination data-link address
D) destination host IP address

Question 2

Describe the purpose of default route (i.e., 0.0.0.0/0) in routing.

Question 3

DHCP (Dynamic Host Configuration Protocol) is a network protocol that enables automatic assignment of IP addresses and other network configuration parameters to devices on a network.

Briefy describe the four steps of how DHCP works. Steps must be in order.

Question 4

Describe the purpose of default route (i.e., 0.0.0.0/0) in routing.

Question 5

DHCP (Dynamic Host Configuration Protocol) is a network protocol that enables automatic assignment of IP addresses and other network configuration parameters to devices on a network.

Question 6

Wireshark is a popular networking tool in IT industry. * 2 points

Describe at least two reasons why Wireshark is commonly used.

Question 7

ARP (Address Resolution Protocol) is a protocol used to map a Layer 3 logical address to a Layer 2 physical address on a local network. How ARP works in local area network?

Question 8

Define unicast, multicast, and broadcast delivery options

Answer 8

Unicast: One-to-one delivery method where a packet is sent from a source to a single destination identified by its unique IP address.

Multicast: One-to-many delivery method where a packet is sent from a source to a group of destinations identified by a multicast group IP address.

Broadcast: One-to-all delivery method where a packet is sent from a source to all devices on a network segment identified by a broadcast IP address.

Question 9

Using a command prompt, execute a command to find out the IPv4 address of cisco.com.
What command that you can use?
What is the IPv4 address of cisco.com?
Convert the IPv4 address to binary format.

Answer 9

nslookup cisco.com

The IPv4 address of cisco.com is 72.163.4.185

01001000.10100011.00000100.10111001

Question 10

TTL stands for Time to Live, which is a field in the IP header of a packet that is used to limit the lifespan of a packet in a network. How TTL works for example in a ping command?

Answer 10

TTL limits packet lifespan. In Ping, it’s set in echo request and decremented by routers. Discarded if zero or destination reached. Helps conserve resources and calculate RTT.

Question 11

Encapsulation is the process where protocols add their information to the data. List the five PDUs in correct order passing down the layers or stack?

Answer 11

Application Layer PDU (message)
Transport Layer PDU (segment)
Network Layer PDU (packet)
Data Link Layer PDU (frame)
Physical Layer PDU (bit)

Question 12

Outline at least 3 differences between TCP and UDP.

Give an example of common application that uses TCP.
Give an example of common application that uses UDP.

Answer 12

TCP is connection-oriented, provides reliability, and uses flow control, while UDP is connectionless, provides no reliability guarantees, and has no flow control. HTTP uses TCP for transmitting web pages, while DNS uses UDP for translating domain names to IP addresses.

Question 13

In the Transport Layer, there are two main protocols: TCP (Transmission Control Protocol) and UDP (User Datagram Protocol). Both TCP and UDP use port numbers.
What is the purpose of port numbers?
Give 2 examples of standard port numbers with the associated service or application.

Answer 13

Port numbers are used in the Transport Layer to allow multiple applications on the same device to communicate over the network. Each application is assigned a unique port number to send and receive data through.

Two examples of standard port numbers with associated services or applications are:

Port 80: This is the standard port number for HTTP traffic, used by web servers to receive and respond to web page requests from clients.
Port 53: This is the standard port number for DNS traffic, used by DNS servers to respond to client requests for domain name resolution.

Question 14

The selection of a network medium depends on several criteria. Outline at least 3 criteria.

Answer 14

The selection of a network medium (also known as a transmission medium or physical layer) depends on several criteria, including:

Bandwidth: The amount of data that can be transmitted over the medium in a given time period. High-bandwidth media can transmit more data per second, which is important for applications that require high-speed data transfer, such as video streaming or large file transfers.
Distance: The maximum distance that data can be transmitted over the medium before it becomes too weak to be detected. Long-distance transmissions require media that can carry a signal over a greater distance without significant degradation, such as fiber optic cable or wireless signals.
Cost: The cost of the medium and associated hardware required for its use. Some media, such as copper cabling, are relatively inexpensive, while others, such as satellite links or specialized fiber optic cables, can be expensive.
Other criteria for selecting a network medium may include reliability, susceptibility to interference, and ease of installation and maintenance.

Question 15

Describe at least 2 similarities and at least 2 differences of OSI Model and TCP/IP Protocol Suite.

Answer 15

Here are two similarities and two differences between the OSI Model and TCP/IP Protocol Suite:

Similarities:

Both models are used to describe the communication process between devices on a network. They both define a set of protocols and standards that enable devices to communicate with each other.
Both models are divided into layers that correspond to specific functions or tasks. Each layer in both models provides a specific set of services to the layer above it, and relies on services from the layer below it.
Differences:

The OSI Model has seven layers, while the TCP/IP Protocol Suite has four layers. The additional layers in the OSI Model provide more granularity and detail, while the TCP/IP Protocol Suite’s simplified model makes it easier to implement and troubleshoot.
The OSI Model is a theoretical model that is not tied to any specific technology, while the TCP/IP Protocol Suite was designed specifically for the internet and is widely used in network communication today. As a result, the OSI Model is more abstract and less practical, while the TCP/IP Protocol Suite is more concrete and relevant to real-world networking.

Question 16

Differentiate physical topology from logical topology.
Give an example of each topology.

Answer 16

Physical topology refers to the physical layout of devices and cables in a network, while logical topology refers to how data is transmitted through the network.

An example of physical topology is a bus topology, where devices are connected to a single cable that runs the length of the network.

An example of logical topology is a star topology, where devices are connected to a central hub and data is transmitted through the hub to the appropriate device.

Question 17

Private and public clouds are two different deployment models for cloud computing.
Briefly describe both the private and public models.

Answer 17

Private Cloud:

Dedicated infrastructure for a single organization
Resources and services managed and maintained internally
Offers greater control, security, and customization
Requires a larger investment in hardware, software, and personnel

Public Cloud:

Shared resources and services over the internet
Managed and maintained by a third-party provider
Charges customers on a pay-as-you-go basis
Offers greater flexibility, scalability, and cost-effectiveness
Less control and security, as data and applications are hosted on shared infrastructure

Question 18

A basic network requires a source which initiates the communication and sends the message, and a destination which receives the message.

Identify and describe at least 3 more components or elements to any communication in a network.

Answer 18

Source: The device that initiates communication and sends the message.

Destination: The device that receives the message.

Protocol: A set of rules and guidelines that govern the format and transmission of data between devices in a network.

Router: A networking device that forwards data packets between networks.

Switch: A networking device that connects devices in a local area network (LAN) and forwards data packets between them.

Question 19

A web client is sending a request for a webpage to a web server. From the perspective of the client, what is the correct order of the protocol stack that is used to prepare the request for transmission?

A) Ethernet - TCP - IP - HTTP
B) HTTP - TCP - IP - Ethernet
C) HTTP - IP - TCP - Ethernet
D) Ethernet - IP - TCP - HTTP

Answer 19

B) HTTP - TCP - IP - Ethernet

Question 20

Which two statements are correct about IPv4 and IPv6 addresses?
(Choose two.)

A) IPv6 addresses are 32 bits in length.
B) IPv4 addresses are 32 bits in length.
C) IPv6 addresses are represented by hexadecimal numbers.
D) IPv6 addresses are 64 bits in length.
E) IPv4 addresses are represented by hexadecimal numbers.
F) IPv4 addresses are 128 bits in length.

Answer 20

B) IPv4 addresses are 32 bits in length.
C) IPv6 addresses are represented by hexadecimal numbers.

Question 21

Describe half duplex and full duplex modes of data transmission.

Answer 21

Half duplex mode of data transmission allows transmission in both directions, but not at the same time.
Full duplex mode of data transmission allows transmission in both directions simultaneously.

Question 22

What is a default gateway?

State at least two features of a default gateway.

Answer 22

A default gateway is a network device that serves as an access point to another network. It acts as a router that forwards traffic between networks.

Redundancy: In some cases, multiple default gateways can be configured to provide redundancy in case one gateway fails or becomes unavailable.

Routing table management: A default gateway is responsible for maintaining and updating the routing table, which contains information about how to reach different networks.

Network segmentation: A default gateway can be used to segment a network into multiple subnets, each with its own default gateway.

Security: A default gateway can be used to implement security measures such as firewall rules and access control lists (ACLs) to control access to and from the network.

Question 23

There are several different types of network architecture, each with its own characteristics and advantages. Client-Server and Peer-to-Peer are just two
of the most common types of network architecture.

Briefly describe both the Client-Server and Peer-to-Peer architectures.

Answer 23

Client-Server architecture is a model in which the workload is divided between the client and the server. The client requests services or resources from the server, which provides the necessary response or resource.

In the Client-Server model, the server is typically responsible for managing resources and providing services, while the client is responsible for requesting those resources and services.

Peer-to-Peer architecture is a model in which all nodes or devices on the network have equal capabilities and responsibilities.

In Peer-to-Peer architecture, there is no centralized server or authority. Instead, all devices are interconnected and can communicate and share resources directly with each other.

Peer-to-Peer networks are often used for file sharing, collaborative work, and distributed computing, while Client-Server networks are used for more centralized services such as email servers, web servers, and database management.

Question 24

You are sitting behind your computer, and you want to download some files from Moodle website.
Refer to the image. Outline the data transmission based on OSI Model’s 7 Layers (from top to bottom). Use the information from the image.

Answer 24

Application Layer: The user opens a web browser and enters the URL for the Moodle website.
Presentation Layer: The web browser formats the request and sends it to the Transport Layer.
Session Layer: The web browser establishes a session with the Moodle server.
Transport Layer: The web browser uses the HTTP protocol to send the request to the Moodle server.
Network Layer: The request is encapsulated into IP packets and sent to the internet.
Data Link Layer: The IP packets are encapsulated into frames and sent to the local network.
Physical Layer: The frames are transmitted over the physical medium, such as Ethernet or Wi-Fi, to the Moodle server.
Upon receiving the request, the Moodle server sends the requested files back to the user following the same layers in reverse order.

Question 25

What is the Layer 2 address used when a destination is on the same local network and when the destination is on a remote network? Why?

Answer 25

The Layer 2 address used when a destination is on the same local network is the MAC address.

The Layer 2 address used when a destination is on a remote network is the MAC address of the default gateway.

The reason for this is that the MAC address is used for communication within a local network, while the IP address is used for communication between networks. When a packet is sent to a remote network, it is first sent to the default gateway, which then forwards it to the appropriate destination network. The MAC address of the default gateway is used for this forwarding process.

Question 26

What command was used to produce this output?
What is the MAC address of the computer?
What part is the the vendor assigned OUI and what part is the Serial number?
Convert the Serial Number to binary format.

Ethernet adapter Ethernet®:

Connection-specific DNS Suffix

Description: Intel(R) 82574L Gigabit Network Connection

Physical Address: 00-0C-29-4E-91-2F

DHCP Enabled No

Autoconfiguration Enabled : Yes

IPv4 Address: 192.168.1.10(Preferred)

Subnet Mask: 255.255.255.0

Default Gateway: 192.168.1.1

NetBIOS over pip: Enabled

Answer 26

The MAC address of the computer is 00-0C-29-4E-91-2F.

The first three octets (00-0C-29) represent the vendor assigned OUI, while the last three octets (4E-91-2F) represent the serial number.

The serial number (4E-91-2F) in binary format is 01001110-10010001-00101111.