OSI Model

Question 1

Encryption resides at what layer of the OSI Model?

Answer 1

Presentation (6)

Question 2

Which layer establishes, manages, and terminates sessions between two communicating hosts?

Answer 2

Session (5)

Question 3

Which layer synchronizes dialog between the Presentation Layers of the two hosts and manages their data exchange?

Answer 3

Session (5)

Question 4

`Which layer has the two main functions for choosing Protocol & Ports?

Answer 4

Transport (4)

Question 5

What layer defines services to segment, transfer and reassemble the data for individual communications between the end devices?

Answer 5

Transport (4)

Question 6

Which layer breaks down large files into smaller segments that are less likely to incur transmission problems?

Answer 6

Transport (4)

Question 7

Which layer provides transparent transfer of data between hosts and is responsible for end to end error recovery and flow control?

Answer 7

Transport (4)

Question 8

Which layer synchronizes and establishes an agreement on procedures for error recovery and control of data integrity?

Answer 8

Application (7)

Question 9

Which layer is responsible for tracking and keeping control of the different sessions on a host known as Session Multiplexing?

Answer 9

Transport (4)

Question 10

Which layer is responsible for Quality of Service (QoS)?

Answer 10

Network (3)

Question 11

Time to Live (TTL) resides at this layer

Answer 11

Network (3)

Question 12

Which layer provides connectivity and path selection between two host systems that may be located on geographically separated networks?

Answer 12

Network (3)

Question 13

Frames reside at which layer?

Answer 13

Datalink (2)

Question 14

Segments reside at which layer?

Answer 14

Transport (4)

Question 15

Bits reside at which layer?

Answer 15

Physical (1)

Question 16

Packets reside at which layer?

Answer 16

Network (3)

Question 17

What process takes place during packet creation?

Answer 17

Encapsulation

Question 18

What is a PDU?

Answer 18

Stands for Protocol Data Unit. A PDU is one chunk of data comprised of Data, Segments, Packets, Frames and Bits. Each one corresponding to the layer in which it came from.

Question 19

What does FCS stand for and what does it do?

Answer 19

Frame Check Sequence. It is error detecting code added to a frame in the datalink layer (2)

Question 20

ICMP lives at which layer?

Answer 20

Network Layer (3)

Question 21

What is the maximum size of a packet?

Answer 21

1500 byte MTU (Maximum Transmission Unit)

Question 22

IP (Internet Protocol) resides at which layer?

Answer 22

Network (3)

Question 23

IPSec lives at which layer?

Answer 23

Network (3)

Question 24

What layer starts and ends the session between devices?

Answer 24

Session (5)

Question 25

How many TCP Ports are available to use?

Answer 25

65,536

Question 26

What are ports used for?

Answer 26

To segment communication

Question 27

Which layer does logical addressing live at?

Answer 27

Network (3)

Question 28

Which layer do MAC Addresses live at?

Answer 28

Datalink (2)

Question 29

How many bits is a MAC Address?

Answer 29

48 Bit Hexadecimal

Question 30

What are the first 24 bits of a MAC Address?

Answer 30

OUI (Organizationally Unique Identifier). It defines the manufacturer

Question 31

What are the last 24 bits of a MAC Address?

Answer 31

Vendor assigned

Question 32

LLDP is a protocol at which layer?

Answer 32

Datalink (2)

Question 33

Ethernet is a protocol at which layer?

Answer 33

Datalink (2)

Question 34

CDP (Cisco Discovery Protocol) is a protocol at which layer?

Answer 34

Datalink (2)

Question 35

Which layer defines specifications needed for activating, maintaining, and deactivating the physical link between end devices?

Answer 35

Physical (1)

Question 36

What is Flow Control?

Answer 36

Flow control is the process of adjusting the flow of data from the sender to ensure that the receiving host can handle all of it