1.3 Packet & circuit switching

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​A local area network (LAN) is any network that covers a small geographical area, typically located on a single site. All the hardware for a LAN tends to be owned and controlled by the organisation using it. LANs are typically connected using: UTP cable Fibre optic Wi-Fi

​A wide area network (WAN) is any network that covers a large geographical area. When multiple LANs physically located in different areas are connected, they form a WAN. The infrastructure that connects LANs to form a WAN is leased from telecommunication companies who own and manage it. WANs are typically connected by: Telephone lines Fibre optic cables Satellite links

Multiple Choice

LAN stands for .....

• Lower area network

• Local area network

• Local area net

• last ace note

Multiple Choice

The network in a school or office is usually a ..

• LAN

• PAN

• WAN

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A network of cash machines is connected in a .

• LAN

• WAN

• PAN

Multiple Choice

Define latency

• Latency is the speed of data processing.
• Latency refers to the amount of data transmitted.
• Latency is the total bandwidth of a network.
• Latency is the time delay in data transmission.

Multiple Choice

What does circuit switching create between the source and destination?

• A permanent link

• A temporary and dedicated link of fixed bandwidth

• An encrypted link

• A multipath route

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What is a characteristic of packet switching?

• Packets always take the same route

• It supports only encrypted data

• Packets can arrive out of order

• It reserves bandwidth in advance

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What provides the basis for traditional telephone networks?

• Packet switching

• Router-based networking

• Internet Protocol

• Circuit switching

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What is guaranteed by using circuit switching?

• The most secure connection

• The lowest cost

• The fastest speed

• The quality of the transmission

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What is a downside of circuit switching?

• It is more expensive

• It requires more complex infrastructure

• It can waste a lot of potential bandwidth

• It cannot support real-time video

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Why is packet switching considered more affordable and efficient than circuit switching?

• Because it requires more complex infrastructure

• Because it uses less electricity

• Because all bandwidth can be used at once

• Because it guarantees the quality of transmission

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How does packet switching send data?

• Through a single dedicated path

• In one large block

• In sequential order

• Into smaller blocks sent independently

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What does packet switching maximize?

• Bandwidth

• Cost

• Security

• Transmission time

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What does packet switching require less of compared to circuit switching?

• Bandwidth

• Complex infrastructure

• Time to transmit

• Data packets

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What is a summary characteristic of circuit switching?

• No physical path for packets

• Reserves bandwidth in advance

• Supports store and forward transmission

• Very little bandwidth wastage

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What is a summary characteristic of packet switching?

• Physical path between source and destination

• Causes a lot of bandwidth wastage

• Packets travel independently

• All packets use the same path

Multiple Choice

What is a key question to answer after watching the video?

• How does the internet work?

• What is the difference between circuit and packet switching?

• What is the best method for data transmission?

• How to build a network?

Multiple Choice

What does packet switching not guarantee?

• The quality of the transmission

• Efficient use of bandwidth

• Affordability

• Independence of packet routes

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Why can packets in packet switching arrive out of order?

• Because they are encrypted

• Because they take the same route

• Because they take different routes

• Because they are all sent at once

video

​https://www.youtube.com/watch?v=UiRw8YDauw0

Multiple Choice

What is a data packet?

• A data packet is a formatted unit of data for transmission over a network.
• A data packet is a type of computer virus.
• A data packet is a physical storage device.
• A data packet is a software application for data analysis.

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What are the main components of a data packet?

• Header, Content, Signature
• Header, Data, Checksum
• Header, Body, Trailer
• Header, Payload, Footer

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What is the purpose of the checksum in a data packet?

• To verify the integrity of the data packet.
• To encrypt the data packet for security purposes.
• To determine the source address of the data packet.
• To compress the data packet for faster transmission.

Multiple Choice

What happens if a packet is lost or corrupted during transmission?

• The packet is ignored and not processed.
• The transmission continues without any changes.
• The packet is deleted permanently.
• The packet is retransmitted to ensure data integrity.

Multiple Select

List all ITEMS a TCP/IP packet switching network packet contains

• Source and Destination IP Address

• Packet number / sequence

• Error detection codes

• Payload

• The encryption key

​The main difference between a router and a gateway is that a router controls traffic within a network, while a gateway connects different networks:


A router's purpose is to connect devices to the internet and manage data within a network. It receives data packets from devices and chooses the best route for each packet to reach its destination.
Routers can also protect information from security threats and prioritize which computers get access to the internet.

A gateway's purpose is to connect two networks and allow data to be exchanged between them. It does this by translating the protocols between the different networks. Gateways can also be used to provide a connection to the internet. In the past, gateways and routers were separate devices, but it's now common for their functions to be combined in a single device called a router.

​https://www.youtube.com/watch?v=KEWe-5Bk3Q0

Multiple Select

What are advantages of dividing network transmission into layers?

• Network communication components are standardised which helps to ensure that different types of hardware and software are able to communicate.

• Through separating the overall network communication processes it makes troubleshooting easier should an error occur.

• To ensure that if changes are made in one layer they do not affect any other layers

• Through dividing overall network communication into smaller, individual components it makes the software development process more straightforward.

• Its easier

Multiple Select

Which of these is correct?

• The APPLICATION layer encodes/decodes the message in a form that is understood by the sender and the recipient.

• Transport layer - breaks down the message into small chunks (packets). Each packet is given a packet number and the total number of packets.

• Network layer - adds the sender’s IP address and that of the recipient. The network then knows where to send the message, and where it came from.

• Data link layer - enables the transfer of packets between nodes on a network, and between one network and another.

• MAC addressing is used by the Network/Internet layer.

Multiple Choice

The purpose of the Application layer is

• Prepares or presents the data (email, file, message) for /from transmission - including applying encryption/decryption

• Ensures reliable transmission of data across the network.

• Ensures the data is correctly routed through the network

• Responsible for encoding the data to be transmitted on the actual cabled or wireless channel.

Multiple Choice

The purpose of the Transmission layer is

• Prepares or presents the data (email, file, message) for /from transmission - including applying encryption/decryption

• Ensures reliable transmission of data across the network.

• Ensures the data is correctly routed through the network

• Responsible for encoding the data to be transmitted on the actual cabled or wireless channel.

Multiple Choice

The purpose of the Internet (or Network) layer is

• Prepares or presents the data (email, file, message) for /from transmission - including applying encryption/decryption

• Ensures reliable transmission of data across the network.

• Ensures the data is correctly routed through the network

• Responsible for encoding the data to be transmitted on the actual cabled or wireless channel.

Multiple Choice

The purpose of the Network Access(or Data Link) layer is

• Prepares or presents the data (email, file, message) for /from transmission - including applying encryption/decryption

• Ensures reliable transmission of data across the network.

• Ensures the data is correctly routed through the network

• Responsible for encoding the data to be transmitted on the actual cabled or wireless channel.

Categorize

Options (13)

The industry standard for sending emails between servers.

SMTP stands for Simple Mail Transfer Protocol.

It is used to send emails from a client to a server or between servers.

POP3 stands for Post Office Protocol version 3.

It is used to retrieve emails from a mail server.

POP3 downloads emails to the client and typically deletes them from the server.

It allows users to access their emails offline after downloading.

POP3 is simpler than IMAP and is suitable for users who access their email from a single device.

IMAP stands for Internet Message Access Protocol.

It allows users to access and manage their email on a remote mail server.

It supports multiple device access, allowing users to view the same email from different devices.

IMAP allows for email synchronization, meaning changes made on one device are reflected on all devices.

It supports folder management, enabling users to organize their emails into different folders on the server.

Organize these options into the right categories

SMTP

POP3

IMAP

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