Why does the cloud storage delete my files without permission?

Recently, major cloud storage services have quietly launched another round of the "Online Content Cleanup Campaign". Do all you seasoned users, just like you always do, open that "study materials" folder you've cherished for years, skillfully click on a video, and get ready to revisit some classic movies?

But instead of the familiar scene, what pops up on the screen is a cold notice of violation and that familiar 8 - second educational video about the online content cleanup campaign.

At that moment, all the study materials you've kept for years vanished into thin air during those 8 seconds of repeated playback.

At this point, I'm sure a big question mark hovers in everyone's mind: "Is there really someone checking my files one by one in the background?"

But if you calm down and think about it, it's actually not very realistic. Let's take a look at some public data for reference:

Several years ago, a leading domestic cloud storage platform announced that it had exceeded 800 million users and the total stored data volume had exceeded 100 billion GB. With such astronomical figures, it's like looking for a needle in a haystack to conduct a comprehensive manual review. It's simply impossible to achieve.

So, the question arises: Since large - scale manual review is unrealistic, how can cloud storage services accurately identify and even instantly delete those illegal files?

This time, let's have a discussion to see how cloud storage services can accurately delete our files.

Before figuring out "how", we need to understand "why". The platform spends so much money and energy, and risks being heavily criticized by us to delete files. There must be reasons behind it. Simply put, there are mainly three reasons.

First and foremost, it is the hard requirement of laws and regulations.

In this regard, there is a classic case that can't be ignored - Qvod. I believe all the old Internet users still remember it clearly. Back then, with its unique P2P on - demand technology, Qvod almost became a haven for pirated and pornographic content.

But what was the final outcome? The company was fined a sky - high amount, the platform was shut down, and the founder went to jail.

The Qvod case was like a thunderbolt, ringing the alarm bell for the entire Chinese Internet industry. Since then, platform providers have to be responsible for the content security on their servers.

According to the law, if a platform fails to proactively review and handle illegal information, it will face a series of serious consequences, ranging from fines to the criminal liability of the person - in - charge.

Therefore, proactively cleaning up illegal content is not an option but a legal obligation for all cloud storage services.

Second, there is the pressure from a large number of copyright complaints.

The various movies, paid courses, cracked software, etc. stored in your cloud drive are not ownerless. Behind them stand numerous companies with powerful legal teams.

Globally, this kind of copyright battle is equally fierce.

A landmark case is the downfall of the once - giant cloud storage service, Megaupload.

In 2012, this website with a huge number of global users was forcibly shut down by the US Department of Justice on multiple charges. One of the charges was that the pirated content on the platform caused losses of over hundreds of millions of dollars to the copyright holders.

This event caused a huge shock globally.

Similarly, in China, if you search for cloud storage copyright infringement in the news, you can find many specific cases. In recent years, the continuous online content cleanup campaigns in China have repeatedly targeted the piracy problem of cloud storage services.

These copyright holders either set up their own rights - protection teams or entrust third - party agencies to monitor the entire network 24/7.

Once they find any infringement, a flurry of infringement notice letters will reach the platform. Therefore, the platform has to delete the files. Otherwise, it will become a defendant, face a lawsuit, and have to pay compensation. In this endless copyright battle, the platform can only "rather kill by mistake than let it go".

As for the third point, which is also the most helpless one, the platform's confidence to do so comes from you. Yes, it's still that classic disclaimer - the user agreement.

I know it's long and boring, and 99.9% of people won't read it. But it clearly states that users are not allowed to upload and share illegal and infringing content, and the platform has the right to handle illegal files without prior notice.

When you check the box to agree, it's like signing an "authorization letter" for the platform's actions. So, both emotionally and legally, the platform has sufficient reasons to screen our files justifiably.

Okay, after understanding the "why", let's explore the core technical question: How does this detection system work?

To balance efficiency and accuracy, this system usually adopts a progressive filtering strategy, like a multi - layer filter. It first filters out the most obvious problems and then conducts a more detailed analysis. This process generally follows the following order:

The first - layer filtering uses the file hash value comparison technology. The hash value can be understood as the "digital fingerprint" of a file. A specific algorithm, such as the commonly used MD5, generates a unique string based on the file content.

This fingerprint only depends on the content itself, has nothing to do with the file name, and any minor change will result in a huge difference.

This technology is commonly used in the "instant upload" function of cloud storage services. When uploading a file, the system calculates its MD5 value and compares it with the server database.

If it matches, it means the file already exists. There is no need to upload it again. You only need to create a link, which greatly saves time and bandwidth.

Similarly, the platform builds a "database of illegal file hash values" and quickly calculates and compares the MD5 values of files during upload. Once a match is found, it can be determined as known illegal content, and the upload will be immediately interrupted or marked.

This method is low - cost, fast, and can efficiently filter out most of the known illegal files.

The second - layer filtering: keyword scanning of file names.

This layer is easy to understand. This technology automatically scans the names of the files you upload or share. If the file name contains high - risk keywords such as "cracked version", "cam - rip", "uncut", the file will be marked as a "suspected target" by the system. It may be directly prohibited from sharing or enter a deeper - level AI review process.

Of course, rules are rigid, but people are flexible. You can always count on the creative and imaginative group of folk experts. Once a review rule is clearly presented, all kinds of experts start to come up with countermeasures.

From initially modifying the file extension, using encrypted compressed packages, to fine - tuning the content by adding a video intro or re - encoding the video, these operations once made traditional detection methods ineffective.

To deal with this situation where there are always countermeasures for every policy, the more technically advanced AI content recognition has become an inevitable choice.

This is currently the layer with the highest technical content and the highest computing cost.

It mainly deals with the files that have passed the first two layers of screening but are marked as "suspected". If the hash value comparison is like checking the "ID card" of a file, then AI technology is like having the ability to directly read and understand the content itself.

Through deep - learning algorithm training, the AI model can directly analyze the picture or video content and identify whether it contains illegal elements such as porn, violence, and bloodshed