Protocols

Question 1

TCP/IP

Answer 1

The Internet protocol suite:
The networking model and set of communications protocols used on the Internet and similar computer networks. It is commonly known as TCP/IP because of its most important protocols, the Transmission Control Protocol (TCP) and the Internet Protocol (IP) .

Question 2

Application layer

Answer 2

Top layer of the TCP/IP stack: an abstraction layer that specifies the shared protocols and interface methods used by hosts in a communications network.

Question 3

What protocols fall under the application layer?

Answer 3

• FTP (File Transfer Protocol)
• HTTP (Hypertext Transfer Protocol)
• HTTPS (Hypertext Transfer Protocol Secure)
• POP3 (Post Office Protocol (v3))
• SMTP (Simple Mail Transfer Protocol)
• SSH (Secure Shell)
• IMAP (Internet Message Access protocol)

Question 4

Link Layer

Answer 4

The bottom layer of the TCP/IP stack. The protocols surrounding the physical and logical connection between components.

Question 5

What happens in the application layer?

Answer 5

Application Layer

The application layer is concerned with providing network services to applications. Sockets and port numbers are used to differentiate the path and sessions which applications operate.

Question 6

What happens in the transport layer?

Answer 6

This layer is concerned with the transmission of the data. The two main protocols that operate at this layer are Transmission Control Protocol (TCP) and User Datagram Protocol (UDP). TCP is regarded as being the reliable transmission protocol and it guarantees that the proper data transfer will take place

Question 7

What happens in the internet layer?

Answer 7

Concerns the sending of data packets across the network, identifying the host IP address and routing the data packets.
A packet contains a source IP Address, destination IP Address and the actual data to be delivered.

Question 8

What happens in the link layer?

Answer 8

This is the lowest level of the TCP/IP protocol stack and functions carried out here include encapsulation of IP packets into frames for transmission, mapping IP addresses to physical hardware addresses (MAC Addresses) and the use of protocols for the physical transmission of data.