If you insert a real-name SIM even once with AntiSpyPhone, will subsequent communications be linked to the carrier?
Since we received a very interesting question, we thought it would be good to share it on our blog, so we wrote an article.
With Anti Spy Phone, if you insert a real-name SIM even once, will subsequent communications be linked to the carrier and lead to identification? In that case, is the only way to anonymize by preparing a different Pixel device and requesting your company again?
I will explain these in order.
The information transmitted to the carrier when a SIM is inserted is as follows.
| Item | Content | Is it transmitted to the carrier? |
|---|---|---|
| IMSI | SIM card unique number (subscriber identification) | Always transmitted |
| IMEI | Device-specific identification number | Always sent during communication |
| Phone number (MSISDN) | Number assigned to the SIM | Usually obtainable |
| Base station information | From which area the communication is taking place | Always known |
| IP address | IP used during communication | Always assigned |
As mentioned above
IMSI, IMEI, MSISDN, etc. are transmitted to the carrier.
This is independent of the OS and is an unavoidable specification as long as you use the mobile network (cellular communication).
In other words, once you use a carrier's SIM, the carrier will have a record of that history.
IMEI spoofing or concealment is basically impossible due to hardware constraints and legal reasons.
By the way,
In Japan (Radio Law):
Under the Radio Law Articles 4 and 113 and the Unfair Competition Prevention Act, alteration of illegal device identification information is considered illegal.
In particular, communication devices using modified IMEI are equivalent to "unapproved technical conformity" and their use itself is subject to penalties.
In other words,
"Not using mobile networks" = the only way to "not send IMEI or IMSI to the carrier."
Specifically,
Method 1: Physically remove the SIM card
If you do not insert a SIM into the device, IMEI and IMSI are not sent to the carrier.
All communication is done via Wi-Fi + VPN or Tor.
If there is no SIM inserted, the device does not access radio waves = it is not under the carrier's control.
Method 2: Airplane mode + Wi-Fi only
If you turn on Wi-Fi while in airplane mode, you can connect to the internet while blocking mobile communication.
IMEI/IMSI are not transmitted to the carrier at all.
It is even safer if you turn on Wi-Fi MAC address randomization.
Methods such as these can be considered.
To maintain complete anonymity, the SIM itself must be completely anonymous.
As you pointed out, for truly anonymous communication, it is necessary to install AntiSpyPhone on the new Pixel.
Next time, I would like to explain about SIM anonymity as well.
