Method and device for allocating MAC addresses in a carrier-current communication network
An improved method of allocating MAC addresses for an electrical distribution network to make it possible to save a great deal of time during the address allocation phase. The method stores, at the central address allocation device, a list of associations between the serial numbers of the devices and the MAC address allocated. The method also sends a cataloging request serving to allocate the MAC address prior to the sending of a communication frame. In this manner, the discovery phases for allocating the MAC addresses to devices without addresses are appreciably reduced. The time when the network is dedicated to such discovery is reduced, thereby increasing accordingly the useful communication time available in the network.
1. A method of allocating addresses, known as MAC addresses, to network devices connected to an electricity distribution network, each network device being provided with a distinct unchangeable serial number, said method being performed by a data concentration apparatus and comprising:
sending a discovery demand request in general broadcast mode over said electricity distribution network;
receiving at least one discovery notification, in response to the discovery demand request, from a network device not having a MAC address allocated, said network device being identified in the discovery notification by means of the serial number;
allocating an available MAC address to the network device that responded to the discovery demand request;
sending a first cataloguing request to the network device that responded to the discovery demand request, said first cataloguing request containing the serial number of said network device that responded to the discovery demand request and the MAC address allocated to said network device that responded to the discovery demand request;
wherein said method further comprises:
storing an association between the serial number of the network device that responded to the discovery demand request and the MAC address allocated to said network device that responded to the discovery demand request;
and wherein said each network device being liable to lose the MAC address allocated to said each network device when a given time period has elapsed without communication, said method further comprises:
storing an information representative of a moment corresponding to a last sending of a communication frame to the network device that responded to the discovery demand request and,
prior to sending a communication frame to the network device that responded to the discovery demand request, sending a second cataloguing request to said network device that responded to the discovery demand request, the sending of the second cataloguing request being performed only if a time period since the moment corresponding to the last sending of the communication frame exceeds a given threshold.
2. The method according to claim 1 , wherein sending the second cataloguing request prior to sending the communication frame is performed systematically for each communication frame transmitted by the data concentration apparatus to said network device to which the communication frame is sent.
3. The method according to claim 1 , wherein said method further comprises:
sending a third cataloguing request, during a phase of system re-initialisation, to any network device for which the association of the MAC address with the serial number has been stored prior to the system re-initialisation.
4. The method according to claim 1 , wherein said method further comprises:
periodically sending the discovery demand request in general broadcast mode to enable the MAC address to be allocated to new network devices that have appeared on said electricity distribution network.
5. The method according to claim 4 , wherein, said each discovery demand request comprising a parameter defining a response percentage, the network devices that do not have an allocated MAC address taking a response decision in accordance with a random drawing with a probability of response equal to the parameter, the parameter is defined with a probability of one hundred percent.
6. The method according to claim 4 , wherein, said each discovery demand request comprising a parameter defining a response window, the network devices responding to one of said each discovery demand request having to define randomly a response time within said response window, said response window is defined as less than 30 seconds.
7. The method according to claim 4 , wherein, said each discovery demand request comprises a parameter defining a response window, the network devices responding to one of said each discovery demand request having to define randomly a response time within said response window, the parameter is calculated according to a number of network devices that have responded to a discovery demand request in a previous discovery phase and according to a number of collisions detected during said previous discovery phase.
8. A device for allocating addresses, known as MAC addresses, to network devices connected to an electricity distribution network, each network device being provided with a distinct unchangeable serial number, comprising:
means for sending a discovery demand request in general broadcast mode over the electricity distribution network;
means for receiving at least one discovery notification in response to the discovery demand request, from a network device not having an MAC address allocated, said network device being identified in the discovery notification by means of the serial number;
means for allocating an available MAC address to the network device that responded to the discovery demand request;
means for sending a first cataloguing request to the network device that responded to the discovery demand request, the first cataloguing request containing the serial number of said network device that responded to the discovery demand request and the MAC address allocated to said network device that responded to the discovery demand request;
wherein said method further comprises:
means for storing an association between the serial number of said network device that responded to the discovery demand request and the MAC address allocated to said network device that responded to the discovery demand request;
and wherein, said each network device being liable to lose the MAC address allocated to said each network device when a given time period has elapsed without communication, said device for allocating addresses also comprises,
means for storing an information representative of a moment corresponding to a last sending of a communication frame to the network device that responded to the discovery demand request and,
implemented prior to sending a communication frame to the network device that responded to the discovery demand request, means for sending a second cataloguing request to the network device that responded to the discovery demand request, the sending of the second cataloguing request being performed only if a time period since the moment corresponding to the last sending of the communication frame exceeds a given threshold.
9. The device for allocating addresses according to claim 8 , wherein said each network device further comprises means for sending a third cataloguing request, during a phase of system re-initialisation, to any network device for which the association of the MAC address with the serial number has been stored prior to the system re-initialisation.