Transmitting and receiving method, communicating device, and local area network

A transmitting method for transmitting data by a communicating device on a communication channel shared by a plurality of communicating devices, the communication over the communication channel being organized according to temporal cycles repeated at a predetermined cycle period, wherein the communicating device is required to transmit data every temporal cycle and the data to be transmitted is repeated from one temporal cycle to the following if no new data to be transmitted is available, wherein said transmitting method comprises, for each temporal cycle:

• determining, by the communicating device, a secured data frame based on the data to be transmitted,
• transmitting, by the communicating device, the secured data frame on the communication channel,
• wherein each secured data frame includes secured content determined by using a predetermined initialization vector, wherein the initialization vector has a lifetime associated thereto which corresponds to a maximum duration during which said initialization vector can remain unmodified, said lifetime being greater than or equal to a predetermined plurality of cycle periods, wherein the initialization vector is not modified when the data to be transmitted in the current temporal cycle is identical to the data transmitted in the previous temporal cycle provided the lifetime of said initialization vector has not expired.