Patent ID: 9185080
Filing Date: 2015-11-10
Classification: G06F,H04L

Abstract:
1. A data transmitting device, comprising: a ciphering method selector configured to select a ciphering method from a plurality of ciphering methods based on a type of data to be transmitted, the plurality of ciphering methods comprising a first ciphering method and a second ciphering method; a ciphering circuit configured to cipher the data based on the selected ciphering method; a data type determiner configured to determine the type of data to be transmitted; a transmitter configured to transmit the ciphered data to a data receiving device; a ciphering method information receiver configured to receive information indicating the first ciphering method and indicating a first ciphering key; and a second ciphering method determiner configured to determine the second ciphering method based on the received information indicating the first ciphering method and configured to determine a second ciphering key from the first ciphering key, wherein the first ciphering key is different from the second ciphering key, wherein the second ciphering method using the second ciphering key is selected to cipher data to be sent on a Slow Associated Control Channel (SACCH) and wherein the first ciphering method using the first ciphering key is selected to cipher data to be sent on a Traffic Channel (TCH), wherein determining the second ciphering key comprises deriving the second ciphering key from the first ciphering key by ciphering the first ciphering key.