What is "SMS zero level"?

Question

JavaScript

I recently stumbled upon a secure cell phone provider ( http://www.vertetele.com) with a ton of goodies for security and anonymity. I saw one interesting statement there "SIM-card ignores
zero-level sms". I had a question, what is "zero level SMS". Googled and found nothing. Connoisseurs, what is "zero level SMS"?

Answer 1

Storage/setItem#Return_value

Answer 2

Hello,
To control phone functions or pre-installed applications, attackers use zero-class SMS, which do not manifest themselves in any way and are not stored on the phone. Such SMS is also called Silent SMS or Stels SMS. All of these requests are directed to the HLR of the issuer's operator. In VERTE, HLR is located in their infrastructure and as a result, they are guaranteed to fix all requests, block them and notify subscribers about attack attempts.
Read about HLR yourself ... Type in Yandex "zero level sms what is this", links will be thrown about these stealths - a bunch ...

Answer 3

Most likely this

Answer 4

Or most likely it is smsc.ru/testhlr
Or in the same place Ping-SMS
But there is no sense in the protection you mentioned, believe me !!))