Chapter 1 - TCP/IP and OSI Networking Models

Question 1

What is the concept when two computers use a protocol (an agreed-to set of rules) to communicate with the same layer on another computer?

Answer 1

Same layer interaction on different computers.

Question 2

What is the concept when on a single computer, one layer provides a service to a higher layer?

Answer 2

Adjacent-layer interaction on the same computer.

Question 3

What is the 5-step process in which a TCP/IP host sends data?

Answer 3

1. Application layer - create and encapsulate the application data with any required application layer headers.
2. Transport layer - encapsulate the data supplied by the application layer inside a transport layer header.
3. Network layer - Encapsulate the data supplied by the transport layer inside a network layer (IP) header.
4. Data Link layer - Encapsulate the data supplied by the network layer inside a data link layer header and trailer.
5. Physical layer - Transmit the bits.

Question 4

What is the data encapsulated in the transport layer called?

Answer 4

Segment

Question 5

What is the data encapsulated in the network layer called?

Answer 5

Packet

Question 6

What is the data encapsulated in the data link layer called?

Answer 6

Frame

Question 7

Which layer encapsulates data with both a header and a trailer?

Answer 7

Data link adds both a header and a trailer

Question 8

What are the 7 layers of the OSI Model?

Answer 8

7. Application
8. Presentation
9. Session
10. Transport
11. Network
12. Data Link
13. Physical

Question 9

What are the 5 layers of the TCP/IP Model?

Answer 9

5. Application
6. Transport
7. Network
8. Data Link
9. Physical

Question 10

What are 6 benefits of a layered protocol specification?

Answer 10

1. Less complex
2. Standard interfaces - Allowing multiple vendors to create products that fill a particular role
3. Easier to learn
4. Easier to develop - Reduced complexity allows easier program changes and faster product development.
5. Multivendor interoperability - Creating products to meet the same networking standards means that computers and network gear from multiple vendors can work in the same network.
6. Modular engineering - One vendor can write software that implements higher layers

Question 11

The TCP/IP model uses terms like segment, packet, and frame. What terms does the OSI model use?

Answer 11

PDU or protocol data unit

Question 12

What is the term that refers to the process of putting headers (and sometimes trailers) around some data?

Answer 12

encapsulation