Some time ago, the CCTV 3.15 party, a small box, a shopping mall, a year of over 100 million user data.

This is the "probe": the mobile phone broadcasts its MAC address, collects and compares it with the database to obtain the user's mobile phone number, and finally integrates big data to get the user portrait.

When the mobile phone turns on the WLAN, it will actively broadcast its MAC address to communicate with the route behind each SSID and communicate with each other. However, the "probe" can collect these MAC addresses and get some additional data, such as in some cases The main purpose of the mobile phone model (more app leaks) and approximate location from the collection device is actually positioning.

After collecting the MAC address, the next step is to compare it. Purchase the corresponding database of mobile phone number and IMEI and MAC address from various App developers (the user has given it permission, and the first two can actually be replaced through many channels, no need Authorization).

So it knows your mobile phone number, compares it with the user database (in fact, simply ask the machine to make a phone call at this time), and the customer's approximate portrait will come out.

Is it scary?

CCTV is exaggerating in this link, but it does not mean that it is less harmful, or that you can prevent it.

Is there any way to prevent the mobile phone?

Of course there is.

Starting from Android O(P), Google has added the option of "Randomly select MAC address when connecting" in the developer options, so that some dangers can be avoided, but unfortunately, in addition to native and similar native UIs, I have seen Most of the manufacturers castrated it. EMUI 8 and MIUI 9 in the CCTV live broadcast are examples of successful recruits.

Of course you still have to activate it (provided that you have this function first)!

Starting from Android Q Beta, Google has provided the option of whether to select a random MAC when connecting in the separate settings of WLAN, and it also needs to be manually turned on.

On the iOS side, the situation has not greatly eased, but it is not much eased compared to five years ago.

Starting from iOS 8, Apple has provided the random MAC address function, but its trigger conditions are extremely harsh. You have to lock the screen, turn off location services, and turn off mobile data before you can use the random MAC function. It also required the latest two generations of iPhone at that time to use this feature.

Fortunately, Apple made a small modification four years ago. Starting with iOS 9, this feature has been gradually added. First, it supports WLAN to turn on random MAC addresses all the time when idle, and it supports all iPhones and iPads after iPhone 5.

Starting with iOS 10, a full-time random MAC address has been made for all devices, regardless of whether they are connected or not. Later iOS made some improvements.

On this issue, we once again see Apple's far-sighted view of user privacy. Apple also automatically randomly generates identification codes such as IMEI to prevent the use of IMEI for tracking

Then the solution is very simple:

Use a machine with a native Android system, and it must be O or higher or Q Beta, the developer settings need to have the option of random MAC address (Sony, Nokia does not)

Or use iPhone 5 or higher, iOS 10 or higher to completely eliminate hidden dangers. Of course, higher iOS versions have more anti-tracking features, such as random IMEI and other identification codes, and the function of prohibiting web pages from reading almost all user data.

Because iOS does not allow apps to read identification codes such as IMEI and phone numbers, it is more difficult to find user privacy.

Most of the domestic mobile phone users have to wait for the update. At present, after a round of inspection, EMUI, Flyme and MIUI have not been castrated, and this is different from the pseudo base station!

It is known that the domestic UI with the function of "randomly select MAC address when connecting" is only part of the beta version of OnePlus H2OS, vivo has deployed a very small version of Android P and the MIUI 10 kernel is a very few development version of Android P.

The late Windows 10 Mobile has similar features, but unfortunately it cannot be enabled when connected.

Why do you still use the iPhone?

Because of the inevitable disclosure of personal privacy, no one can stop it. Let's look at the privacy policy next time. Of course, if you used an Android phone before and were collected, you would only have to change the number.

Of course, ensuring the security of your Wi-Fi connection is the most necessary. Although the "probe" is detecting our privacy. But the router at home does not pose a security risk! Don't be a soldier!