2 - Network Models

Question 1

What is ISO?

Answer 1

International standards organization.

Multinational body dedicated to worldwide agreement on international standards.

Question 2

What is OSI?

Answer 2

Open Systems Interconnection model.

Question 3

What are the seven layers of the OSI model in order from highest to lowest?

Answer 3

• Application
• Presentation
• Session
• Transport
• Network
• Data link
• Physical

Question 4

What is the physical layer responsible for?

Answer 4

Movements of individual bits.

- From one hop to the next.

Question 5

What is the data link layer responsible for?

Answer 5

• Moving FRAMES from one hop to the next.

- Transforms the physical layer to a reliable link, organize bits into frames.

Question 6

What is the network layer responsible for?

Answer 6

For the delivery of individual packets from the source host to the destination host.

Question 7

What is the transport layer responsible for?

Answer 7

For the delivery of a message from one process to another.

Question 8

What is the session layer responsible for?

Answer 8

For dialog control and synchronization. (half-duplex/full-duplex)

To establish, manage, and terminate sessions.

Question 9

What is the presentation layer responsible for?

Answer 9

For translation, compression, and encryption.

Question 10

What is the application layer responsible for?

Answer 10

For providing services to the user.

Question 11

What are the four levels of addresses used in an internet employing the TCP/IP protocols?

Answer 11

Physical, logical, port, and specific.