Method and device for transmission of entitlement management messages

A method for transmitting entitlement management messages (EMM) controlling access to data and/or services to be provided to a plurality of terminals in a data exchange network, the method comprising:

• at transmission:
• defining a set of EMM type messages as a function of at least one criterion representative of a type of data and/or services provided,
• defining a plurality of types of logical transmission channels and associating at least one parameter to each type of channel to inform terminals of the EMM types transmitted on each described logical channel,
• assigning at least one channel among the defined logical transmission channels to each EMM message type,
• transmitting the parameter and the logical channels to each terminal,
• multiplexing the logical transmission channels in a unique data stream, and
• transmitting the data stream to terminals;
• and
• at reception:
• each terminal filtering incoming EMMs as a function of the parameter and at least one state parameter depending on a routine operation of the terminal, wherein, the parameter is transmitted to each terminal in a dynamic data structure representing a logical control channel, comprising at least one of the following fields:
• a first field configured to enable the terminal to identify the logical channel descried by the structure,
• a second field configured to inform the terminal about a change to data and/or change to the dynamic structure corresponding to transmission of new data on the described channel such that the terminal adapts its filtering to retrieve the new data, and
• a third field configured to inform the terminal about a listen time on the described channel,
• wherein the types of defined logical channels comprise at least:
• a FAST channel configured to transmit EMM messages to terminals that expressly requested these messages;
• a DEDICATED channel configured to transmit EMM messages with identical functional objectives;
• a NORMAL channel configured to transmit EMM messages for which contents are not predictable and may not be delayed in time;
• a DELAYED channel configured to transmit to terminals non-urgent EMM messages with plural functional objectives;
• and
• a LOAD SHEDDING channel configured to retransmit messages that have already been transmitted on a channel other than the DEDICATED channel, to terminals.