Why do all books write about the OSI model, if the Internet uses TCP IP everywhere?

Question

Computer networks

Why is everyone studying the axis model if it is written that the modern Internet operates according to the principles and protocols of tcp ip?

i.e. the tcp ip model and the 4-layer protocols of this model work everywhere, and we are studying osi. what is the logic here?

Answer 1

This is rooted in history. In the early nineties, a group of engineers long and tediously procrastinated (of course, not for free) the standard of networking. The same OSI model. They argued and proved their case (of course, not for free), they could not come to some kind of common decision in the end. It seems that this wave dragged on for several years (of course, not for free).
While some boobs were crushed, it was necessary to somehow develop and expand. There were many communication protocols: IPX, Frame Reley, .x25, IP. In the end, only the IP/TCP solution survived. The OSI model remained on paper and as a reminder to posterity.

and we are learning osi. what is the logic here?

To have something to answer in interviews. Usually they only ask about it. They ask those who were asked before, etc.
At social security, they can also ask other old things: about vlan; types of network topologies (someone is sure to be talking about token ring); what is the difference between hub and switch-a .... I think the logical chain is clear.

Answer 2

Why is everyone studying the axis model if it is written that the modern Internet operates according to the principles and protocols of tcp ip?

In order to study, so as not to say such nonsense out loud.
Read, specify what OSI level occupies tcp / ip and how many MORE protocols are actually found on the modern Internet.

Answer 3

You are mixing things up a bit.
The OSI model is an abstract model that shows how communication takes place between two points in a network.
The first level describes the physical world, the last level is the application itself.
TCP/IP is just Layer 3 and Layer 4 of the OSI model. Each level describes its own set of logic for maintaining communication.
This model is not useless, it helps to understand how traffic flows very well, and understanding this model helps to troubleshoot problems.
If you don't have a link then it's pointless to talk about ip, TCP, poppy addresses.
Or if you see that the service sent a 403 error, you can be sure that routing is working for you, packets go between two points, but there are problems in the application.

Answer 4

It's just a fairy tale! As long as the new generation is confident in its superintelligence and the uselessness of anything old, we will have work and a sandwich with black caviar.
OSI is not needed, do not learn! How nice it is to see crowds of laymen on the network who consider themselves Specialists who are not able to formulate which switch they need L2 or L3 :)

Answer 5

Google what TCP is and what OSI is, just do
n’t tell the PS definitions themselves to a person, let him learn to google)

Answer 6

https://linkmeup.ru/sdsm/

Answer 7

Now everywhere they give a lot of dope. It's still left over from the advice. You just have to come to terms with the fact that a modern book is, for the most part, water and a source of income, not knowledge.
In addition, OSI is in fact a stillborn model. If the book says more about OSI than about anything really used, then this is immediately a trigger.

Answer 8

The simple answer is not everywhere.