Hey, this is TT! My schedule during golden week, which is Japanese long vacation in May, was canceled due to state of emergency. Although the cancel is dissapointing, this is a good opportunity to work on study for IT.
Previouslly, I introduced a structure of computer and communication protocol. This time, I would like to explain “Client-Server model”, supporting communications among computers, to learn together. Frankly speaking, I need to mention detailed communication standard, yet I will touch it in the future.
I mentioned 5 devices for computers (Control device, Arithmetic device, Storage device, Input device and Output device) before, but these devices are not enough to establish communication among computers. Assuming the world which only a computer exists, even if we typed “What is IT?” in searching browser, nothing happens. This is the same when you live alone and ask “What is dinner today?”, then nobody replies.
Among computers, there is “Server-Client model”, which is composed by client that request service (actual process) and server that responses to the request. Back to the example of searching, when you type “What is IT”, your computer becomes client. In the back, a large computer called a server presents a related page that searches for information behind PC screen. If you live in your parents’ house, when you go home asking “What’s your meal today?”, Your mother will reply “It’s curry rice.” Here, you are the client when you hear “Today’s rice”, and the mother who replies “It’s curry rice” acts as the server.
The computer builds this client / server relationship with all its features. As mentioned earlier, in Internet search, a server called a communication server provides data for related pages, and for sending and receiving emails, a server called a mail server links emails addressed to you and sends the created emails to the other party. I will. The city that prints the materials prints the format entered by the printer server on paper.
Conclusion
This time, I covered rough computer communication. The contents covered today are as follows.
- Computer alone cannot communicate with other computers.
- Communication between computers is realized by a client that requests (requests) a service (actual processing) and a server that responds (provides) the requested service in a client-server model.
Communication between computers is not only possible when requesting a service, but also when there is a partner called a server. In the IT world, all services are built with this client and server, so understanding this mechanism will change the way you see the mechanism of a familiar computer.
As mentioned at the beginning, there are various standards of communication between the client and the server, and I think that understanding will be further deepened by decomposing the elements related to communication, so I will discuss them in the future.
Thank you!
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