Hello, Ejnstok Fajr, you wrote: whether > It is possible to install connection similar on TCP with the person, using telephone number informed by this person? Telephone number in a cellular network - no more than human-friendly a method to designate the subscriber. The main operation on identification becomes through IMSI is the spets-identifier which has been sewn up in a sim card (together with encrypting keys and other ). Theoretically, nothing forbids to have between telephone numbers and lists IMSI a ratio many-to-many, rather interesting scenarios like serial dialup a-lja Load balancer or seamless passage of a call from a device on a device "a mobile phone-> hends-fri in the machine-> speakerphones in the clever house". It can simply not be supported by the given operator, the given cell, can be a part of paid dop-service etc., etc. > Me the routing system in a network which does not demand static IPv4-addresses interests. > it Is necessary for me for creation P2P of application on the basis of WebRTC Well, it is solved. It is necessary to get only a server where subscribers will send actual IP, and to put in the protocol assurance of receipt (not to confuse to similar mechanism TCP). Then it will be possible to mark that has been completely received by the subscriber before change IP and that is necessary .