Shulou(Shulou.com)06/02 Report--

The network disk has been developed for many years. I vaguely remember that there have been a large number of network disk services on the network since 12 years ago, such as all kinds of network disk represented by 115. at that time, the companies that could call the number all carried out their own network disk services. brush the sense of existence in the Internet service, and then close down one after another. think about it, what are the other surviving network disk services, Baidu Network disk, Huawei Cloud disk, Tencent Weiyun and so on. These big factories are still providing these services, so what is the network disk? Is this product really so far away from us? Not necessarily, let's experience the evolutionary history of online disk in detail.

What is the net disk?

Is this thing really a big Internet plate? That's not true. In fact, this is also a kind of cloud service. Exactly speaking, it should be a network storage system, which is called NAS,Network Area Storage. Such a high-end term is put aside for the time being. Let's turn our eyes back and think about a question: how can we save a picture on our mobile phone after taking a picture? After the shutter clicks, the photosensitive module forms an image, and the phone's CPU processes the image to form a file, which is then read from memory and stored in the phone's storage space with the suffix .jpg.

This process looks very simple, using the function is a part of the computer software system called file management system, this system is still a very important storage management tool, of course, this tool and the previously mentioned NAS has important reference significance, because in this process of saving pictures (files) to the mobile phone, IT engineers have a name, local storage. So what do we do when the local storage is full? we can only erase the old pictures, otherwise how can we continue to save them? But the fairies are very proud and coquettish, the photos are so precious, how can each one be deleted? Since the mobile phone can't save so much, why don't you just change the phone and change it to a bigger one? For a larger process, the storage engineer, named vertical upgrade, and the development engineer talking about iterative upgrade, are all talking about the same thing. Well, I also think IT people are a little bored at this point. What if there is no money? I also want to upgrade! Can I insert a memory card? I'll buy 8g or 16g of a card. Well, under the premise that the phone has an expansion slot, this can indeed be done. In the storage project, this operation is called horizontal upgrade. However, here comes the question again: how many mobile phones have expansion slots now? Whether it is urgent or not, there are new operations.

Put it on the cloud

Where is the cloud? Heaven, that picture how to go to heaven, ah, through the network, we just saw the picture will know that this .jpg file will be saved from memory to the local, now will be transmitted through the network, no longer to the local, run to the sky, in fact, it is the Internet service provider (Internet Service Provider, such as Baidu, Tencent) on the computer (in fact, the server). The process of transferring from mobile phone to cloud and storing it to other people's devices depends on a simple network, and network engineers have a name for this process, the network area stores Network Area Storage.

Nowadays, the concept of cloud is becoming more and more substantial. What everyone can use is called public cloud, and what only you and your friends can use is called private cloud. Of course, if you agree that part of the space can be shared with everyone, it is called hybrid cloud. The clouds are boundless, sometimes east and west, and I have no idea where these beautiful pictures (files) are stored. Ladies and gentlemen, are you relieved to use it?

Why not build a cloud disk yourself?

Realization idea

With the development of computer network for decades, it is still inseparable from the TCP/IP protocol stack, and so is the network disk. The underlying connection between the mobile phone and the cloud is still the communication between the TCP server and the client. This communication process is called three-way handshake.

This simple three-sentence conversation is the process of shaking hands (does it feel like a slap in the mouth)? after greeting, of course, you can send pictures (documents). This must have been done 30 years ago, but, uh, this process is really annoying. Both the sender and the receiver have to consider a lot of things, for example, whether the picture sent is too large, can it be cut smaller, if the other side is cut small, how to spell it back when it is received, how do I know if the other party has received the picture? These questions have to be considered in the transmission process of every document, whether you say it is annoying or not, anyway, if you think about it too much, you will certainly be bald. So after many efforts, the network engineers packed all these communication processes into a big box, called http, well, now we know that http said that the transmission upgrade version of tcp is better than blue, and http can send files more conveniently, whether or not to cut small files, and how fast to send these things do not need to consider, this product is done for you.

Then came the programmers who influenced the process of the world. With both hands, they instructed http to automatically send, send and accept all kinds of indescribable files. Programmers are sure to quarrel, you see, php is not the best language for how many years, but not continue to quarrel, so a group of bad old men jumped out and said, shut up, we all have to abide by an agreement, Hello, he is good, everyone is really good, the agreed name is RESF, all you have to do is to achieve RESFful API,OK?

Hey, not to mention the standard communication, the communication cost is low, java, python, go. The http server built by these language tools can talk well. However, here comes the problem again: how do these strange uncles know what programmers are talking about? Oh, no wonder there are only 10 kinds of people in the world, one who knows binary and one who doesn't. We can only use this to complete the data transmission and transmission, but there is no way, ah, survival is still necessary, you have to serve you well, will be willing to pay us ah. You guys are the bosses, okay, Orz?

We can upload and download files remotely by clicking a number of buttons through the terminal, but for non-programmers, this operation is really helpless.

So in order to make you comfortable, pleasant to operate, experience and free, the programmers repackaged the process, saying that this is a big plate, and you can put everything into it, ensuring that it is safe and accessible at any time, and the space will temporarily give you 2T. If you charge money, you can also wear a crown, upload faster and download stronger.

These are the results of the code work of the final development engineers, the crystallization of the design of product managers, and the good experience provided by service providers to users, so wouldn't it be exciting if we make one ourselves? Everyone will guess when you read this. In fact, the so-called cloud disk is a server waiting for you to visit at any time for application development, just like a senior butler, waiting for the call of your viewers at any time. All we have to do is surf the Internet and log in to the account for the rest of the operations, such as automatic upload and save, file persistence management, deletion of duplicate files, and other operations, which are done by the butler.

Well, this is roughly the end of the review of the evolutionary history of the network disk. To put it bluntly, it is the change from the local disk to the network disk, which depends on the development of the computer network. Imagine that when the 5G era comes, under the premise of good network quality, all our mobile phones no longer need to be stored. If you like to take pictures, just store them on the network disk. If you want to review them, go to the network disk and look for them. The downloaded application is directly stored on the network disk, and if you want to run it, you can run it on the network disk. This imagination is actually the so-called cloud desktop application. For the imagination of faster and faster network speed and wider and wider bandwidth, hee hee, the future can be expected.

Next time, let's talk about simple source code implementation.

Having said so much, the next article shares a simple code implementation.

Welcome to subscribe "Shulou Technology Information " to get latest news, interesting things and hot topics in the IT industry, and controls the hottest and latest Internet news, technology news and IT industry trends.