Chapter 2 OSI Layers

Question 1

Host 1 sent a SYN packet to host 2. What will Host 2 send in response?

Answer 1

SYN/ACK

Question 2

TCP and UDP reside at which layer of the OSI Model?

Answer 2

4

Question 3

Which layer of the OSI model provides an entry point for programs to access the network infrastructure?

Answer 3

Application

Question 4

You are connected to a server on the internet and you click a link on the server and receive a time-out message. What layer could be the source of this message?

Answer 4

Application

Question 5

Which layer of the OSI model is responsible for code and character-set conversion as well as recognizing data formats?

Answer 5

Presentation

Question 6

At which layer of the OSI model do bridges, hubs, and routers primarily operate, respectively?

Answer 6

Data Link, Physical, Network

Question 7

Which layer of the OSI model is responsible for converting data into signals appropriate for the transmission medium?

Answer 7

Physical

Question 8

A receiving host has failed to receive all the segments that it should acknowledge. What can the host do to improve the reliability of this communication session?

Answer 8

Decrease the window size

Question 9

Which layer 1 devices can be used to enlarge the area covered by a single LAN segment?

Answer 9

Hub and Repeater

Question 10

Segmentation of a data stream happens at which layer of the OSI model?

Answer 10

Transport

Question 11

When data is encapsulated, which is the correct order?

Answer 11

Data, segment, packet, frames, bits

Question 12

What are two purposes for segmentation with a bridge?

Answer 12

To create more collision domains

to add more bandwidth for users

Question 13

Acknowledgments, sequencing, and flow control are characteristics of which OSI layer?

Answer 13

Layer 4

Question 14

Which of the following is true regarding sequencing and acknowledgments?

Answer 14

The segments delivered are acknowledged back to the sender upon their reception

Any Segments not acknowledged are retransmitted

Segments are sequenced back into their proper order upon arrival at their destination

Question 15

What is the purpose of flow control?

Answer 15

To provide a means for the receiver to govern the amount of data sent by the sender.

Question 16

At which layer of the OSI model would you find IP?

Answer 16

Network Layer

Question 17

Of the following, which is the highest layer in the OSI model?

Answer 17

Presentation Layer

Question 18

Routers perform routing at which OSI layer?

Answer 18

Network Layer

Question 19

Which IEEE standard specifies the protocol for CSMA/CD?

Answer 19

802.3