The document describes a pizza order process while drawing parallels to the OSI model of networking layers. It explains each layer's function in the context of ordering a pizza, from the application layer to the physical layer, emphasizing the importance of communication and routing in both pizza delivery and data transmission. The narrative illustrates how technology can be likened to everyday activities like ordering food.

1. I think tonight I will
order pizza for delivery.
It sounds so good!
FOOD ORDER
1 Large
sausage
Order #21
#21
w/veggies
Hi, this is Pizza
Palace. What can I
get for you?
I will have 1 large
sausage pizza with
veggies.
FOOD ORDER
1 Large
sausage
Order #21
#21
w/veggies
PIZZA
John
Okay that was a large
sausage pizza with
veggies. That will be
$12.75.
PIZZA
Pizza order #21 is
ready for delivery!
PIZZA
Thank you for the
speedy delivery!
No problem!
Enjoy your pizza!
5678 AvenueDestination
Head north toward Chino Hills Pkwy
138 ft
Turn right onto Chino Hills Pkwy
0.6 mi
Turn left onto Central Ave
0.8 mi
Take the 3rd left onto Bell Ct
Destination will be on the right
230 ft
PIZZA
GPS will get
me there in no
time!
PIZZA
I’m here but
I still have to
find the right
appartment!
The application layer is the user interface that receives commands from users. Clicking on a link on an internet browser is akin to a
customer dialing on their phone to order a pizza.
You can think of the transport layer as quality control. Suspicious packets will not make it past a firewall. Similarly, low-quality pizzas will
not go out for delivery.
The network layer determines the best way to route information. Similarly, our pizza delivery person will rely on a GPS to map out a
customer’s location.
The physical layer comprises of the physical hardware components in a network. In this final step, our now starving customer will receive
her delivery.
One of the major functions of the data link layer is to provide a physical MAC address so that requested information can find its destination.
Without a physical address, our pizza delivery man would not be able to complete his delivery.
The presentation layer translates requests received from the application layer into a common networking language. In order for our pizza
customer to place an order, she needs to speak a common language with the person taking her order.
This layer can be compared to making a phone call and having the other person pick up the phone. Without another party on the line, no
food-related or network-related conversation would occur.
Layer 7: Application
Layer 6: Presentation
Layer 5: Session
Layer 4: Transport
Layer 3: Network
Layer 2: Data
Layer 1: Physical
OSI Model Explained: Pizza Style
TECHNOLOGY
NORTH AMERICAN DISTRIBUTOR
PLANET