The invention relates to an addressing method for bidirectionally sending electronic messages between a communication application comprising a sender identifier (OIDi) and an interactive terminal comprising a recipient identifier (MSISDNj) via a transmission system. OIDi and MSISDNj comprise standardized data formats while the terminal is equipped so as to communicate with terminals using recipient identifiers in the OADCi format. The transmission system assigns a dynamic reply identifier (OADCi) to the communication application comprising the sender identifier (OIDi), which sends a message that is addressed to the terminal comprising the MSISDNj identifier, 1) said assignment being valid for the MSISDNj terminal; 2) said assignment being valid for a given finite lifetime (Ti); 3) the reply identifier (OADCi) being selected among a finite pool of n identifiers (OADC1 to OADCn); and 4) the reply identifier (OADCi) being added to the message that is to be transmitted as a sender identifier.
