1.3.3.3 Network Protocols

Question 1

What is a network protocol

Answer 1

A set of rules dictating how computers interact and send data across a network

Question 2

What are the situations that protocols handle?

Answer 2

• Handshaking – How communication start and end
• Which network port communication should be over
• Transmitting data
• What to do in case of errors
• If data is sent and received correctly

Question 3

What is the Transmission Control Protocol (TCP)?

Answer 3

A protocol based around sending data across different networks/systems.

Question 4

How are packets structured?

Answer 4

Each packet is composed of a header (title and details on how the packet reaches its destination) and a payload (the data itself)

Question 5

What is the Internet Protocol (IP)

Answer 5

A protocol dictating how data is sent across different networks, working across the internet, a WAN.

Question 6

What are the contents of the IP header and IP address?

Answer 6

The IP header contains a source and destination IP address which allows the router to know who should be connected and who shouldn’t.

Question 7

What are the four layers of the TCP/IP stack in their order? (1 - 4)

Answer 7

• Application
• Transport
• Network
• (Data) Link

Question 8

What is the application layer of the TCP/IP stack? What protocols make this layer?

Answer 8

Data delivery among applications. Includes Telnet, FTP, HTTP(S), SNMP

Question 9

What is the transport layer of the TCP/IP stack? What protocols make this layer?

Answer 9

Process to process data delivery. Includes UDP, TCP

Question 10

What is the network/internet layer of the TCP/IP stack? What protocols make this layer?

Answer 10

Host to host data delivery. Includes IP, ICMP, Routing Protocols.

Question 11

What is the link layer of the TCP/IP stack? What protocols make this layer?

Answer 11

Hides details of physical network. Includes, Network interface, drivers

Question 12

What is the WPA-2 protocol?

Answer 12

A Wi-Fi protocol encrypting data transmitted wirelessly.

Question 13

What are the 3 email protocols?

Answer 13

• Post Office Protocol (POP)
• Internet Messaging Access Protocol(IMAP)
• Simple Mail Transfer Protocol (SMTP)

Question 14

Which email protocol is used for sending emails?

Answer 14

Simple Mail Transfer Protocol (SMTP)

Question 15

Which 2 email protocols are used for receiving emails?

Answer 15

• Post Office Protocol (POP)
• Internet Messaging Access Protocol (IMAP)

Question 16

What is the difference between POP and IMAP. Which is more reliable and used more these days?

Answer 16

POP deletes the email from the server once they’ve been read, whereas IMAP keeps the emails. This makes IMAP far more reliable and viable these days as you can read emails on all of your devices.

Question 17

What does the S in HTTPS mean?

Answer 17

‘Secure’. This means that there is a security layer in the webpage, providing protection.

Question 18

What does HTTP stand for? What does it do?

Answer 18

Hypertext Transfer Protocol. Handles Webpage requests

Question 19

What transport protocol is used in client-servers?

Answer 19

File Transfer Protocol (FTP). When you interact with the program, the client generates the appropriate responses.

Question 20

What size network do we see FTP commonly function on?

Answer 20

WAN

Question 21

What does UDP stand for and where would it place on the TCP/IP stack?

Answer 21

User Datagram Protocol. Transport layer

Question 22

How does UDP differ from TCP?

Answer 22

• UDP uses a simple connectionless transmission model.
• UDP uses no error checking, thus less reliable than TCP.
• UDP is used to send short messages using datagrams.

Question 23

What makes UDP beneficial for online gaming?

Answer 23

• Maintains an open two-way connection
• Prioritises speed over accuracy.

Question 24

What is a router?

Answer 24

A device that connect a LAN to another LAN/WAN to form/become part of a WAN. It forwards packets between computer networks. Routers perform the traffic directing functions on the Internet.