OSI Reference Model

Question 1

What is layer 1 of the OSI model?

Answer 1

Physical

Question 2

What is layer 2 of the OSI model?

Answer 2

Data Link

Question 3

What is layer 3 of the OSI model?

Answer 3

Network

Question 4

What is layer 4 of the OSI model?

Answer 4

Transport

Question 5

What is layer 5 of the OSI model?

Answer 5

Session

Question 6

What is layer 6 of the OSI model?

Answer 6

Presentation

Question 7

What is layer 7 of the OSI model?

Answer 7

Application

Question 8

Name four common OSI layer 3 protocols

Answer 8

Network layer - IPv4, IPv6, ICMP, IPSec

Question 9

Name four common OSI layer 7 protocols

Answer 9

Application layer - HTTP, FTP, SSH, DNS

Question 10

Name two common OSI layer 4 protocols

Answer 10

Transport layer - TCP & UDP

Question 11

Name three common OSI layer 2 protocols

Answer 11

Ethernet, PPP (point to point), WiFi

Question 12

What is a PDU?

Answer 12

Protocol Data Unit

In networking, a protocol data unit (PDU) is the basic unit of exchange between entities that communicate using a specified networking protocol.

Question 13

What is a PDU called at layer 3?

Answer 13

Packet (network layer)

Question 14

What is a PDU called at layer 2?

Answer 14

Frame (data link layer)

Question 15

What is a PDU called at layer 4?

Answer 15

Segment (transport layer)

Question 16

Which layer does ARP operate at?

Answer 16

Layer 2 (data link layer)