Abstract: Method for transporting asynchronous data and synchronous non coded information NCI bits on a common channel operating at (n+1)/T bits per second, in slot of duration T containing n+1 bits, the data and NCI portions of the bit stream to be transported being delimited by a flag having a specific pattern which cannot be simulated by the data bits. During the periods where there is an NCI activity, the first n bits of the slot are used for transporting NCI bits and the last bit is used for transporting an additional data bit, if the said first n bits are different from the flag pattern and said last bit is set to a first binary value (0) if said first n bits are similar to the flag pattern. During the periods where there is no NCI activity, data bits are sent in at least one slot delimited by two slots, the first n bits of which are set to the flag pattern and the last bit of which is set to the second binary value (1).