Method for transmitting data and system comprising communicating entity

A method for transmitting data by hops between communicating entities, said communicating entities comprising:

• one master entity, configured for communicating according to a first cyclic Ethernet protocol and according to a second cyclic Ethernet protocol, and
• a plurality of slave entities, comprising:
• a first group of slave entities able to support communications according to said first protocol and unable to support communications according to said second protocol, and
• a second group of slave entities able to support communications according to at least said second protocol,
• said first protocol being implemented by a token passing transmission with communication data from the master entity to successively each neighbour slave entity, until the token reaches again the master entity, defining thus a first cycle according to the first protocol, one current entity of said first group, when receiving an Ethernet data frame, being configured so as to:
• process said data frame and transmit the processed frame according to the token passing transmission, if said Ethernet data frame is according to the first protocol,
• or ignore the content of the data frame and simply transmit said data frame to a next neighbour entity upon its reception, if said Ethernet data frame is according to the second protocol,
• said second protocol being implemented by passing an Ethernet data frame including data intended to entities of said second group, one current entity of said second group, when receiving said Ethernet data frame, being configured so as to:
• modify said data frame by taking from said data frame data intended to said current entity and/or by adding into said data frame data intended to other entities of said second group, and
• transmit the data frame thus modified to a neighbour entity, successively until the data frame reaches said current entity, defining thus a second cycle according to said second protocol,
• wherein said master entity is configured to support communications according to both first and second protocols, and is configured further to:
• start the first cycle;
• start the second cycle, and chose in the second group at least one slave entity to start the second cycle at the same time as the master entity starts the second cycle.