31-03-2022 дата публикации
Номер: US20220104013A1
A method to attach a mobile device to a server, using a protocol having data size encoding constraints which prevents using traditional ciphering, includes an initialization phase using a range of ephemeral IMSIs stored in a batch of credential containers of mobile devices and an associated group master key shared by the server and credential containers having the same range of ephemeral IMSIs to initiate a session using a server random value. The initialization phase uses limited payload in a mobile device-to-server message to send a randomly chosen rIMSI among the range of IMSIs to enable the server to generate keys to initiate a secured communication phase, then using individual keys stored in the mobile device and retrieved by the server with an identifier of the credential container sent in a mobile device-to-server message and with an individualization master key owned by the server. 1. Method to securely attach a mobile device having a credential container to a server while using a protocol having data size encoding constraints which prevents using traditional ciphering , such constraints comprising at least:a constraint related to the number of data payload in each exchange specifically in the mobile device to server direction,a constraint related to the dissymmetry of the size of data payload in the server to mobile device direction and in the mobile device to server direction, anda constraint related to the impossibility to cipher some data in the data payload,said method comprising an initialization phase using a same range of ephemeral IMSIs stored in a batch of credential containers of mobile devices and an associated group master key shared by the server and the batch of credential containers of mobile devices having the same range of ephemeral IMSIs to initiate the secured session further using a server random value, said initialization phase using limited payload in a first mobile device to server message to send a randomly chosen rIMSI among the ...
Подробнее