OSI MODEL

Question 1

OSI Definition

Answer 1

Open System Interconnection

Takes into account the flow of data from physical connection up to end user application

Question 2

OSI LAYERS

Answer 2

Physical
Data Link
Network
Transport
Session
Presentation
Application

Question 3

OSI LAYER how to remember

Answer 3

“Please
Do
Not
Throw
Sausage
Pizza
Away”

Question 4

PHYSICAL LAYER

Answer 4

The actual hardware (cables, switches)

Think: “The physical stuff you can touch”

Example: Electrical signals, cables, pins

Question 5

DATA LINK LAYER

Answer 5

Connects devices on the same network

Think: “Making sure data gets to the next device safely”

Example: MAC addresses, error detection

Question 6

NETWORK LAYER

Answer 6

Routes data between different networks

Think: “Finding the best path like a map”

Example: IP addresses, routers

Question 7

TRANSPORT LAYER

Answer 7

End-to-end connection and reliability

Think: “Making sure all pieces arrive correctly”

Example: TCP/UDP, port numbers

Question 8

SESSION LAYER

Answer 8

Manages communication sessions

Think: “Starting, maintaining, and ending conversations”

Example: Setting up, coordinating communication

Question 9

PRESENTATION LAYER

Answer 9

Data translation and encryption

Think: “Translating data into a usable format”

Example: JPEG, encryption, ASCII/EBCDIC conversion

Question 10

APPLICATION

Answer 10

User interface and network services

Think: “What the user actually sees and uses”

Example: HTTP, FTP, email