变速箱链条的参考配置如GSM 05.01所示。根据该参考配置，本技术规范规定了提供给加密单元的数据块。它包括编码、重排序、交织和窃取标志的规范。它没有指定信道解码方法。给出了每种逻辑信道的定义，从语音编码器、数据终端设备或MS或BS控制器提供给信道编码器的数据开始。 GSM 05.02中给出了本技术规范中使用的逻辑信道类型的定义，附录1中给出了摘要。

A reference configuration of the transmission chain is shown in GSM 05.01. According to this reference configuration, this technical specification specifies the data blocks given to the encryption unit. It includes the specification of encoding, reordering, interleaving and the stealing flag. It does not specify the channel decoding method. The definition is given for each kind of logical channel, starting from the data provided to the channel encoder by the speech coder, the data terminal equipment, or the controller of the MS or BS. The definitions of the logical channel types used in this technical specification are given in GSM 05.02, a summary is in annex 1.