Protocol for network having plurality of intelligent cells

• US 4,955,018 A
• Filed: 11/08/1988
• Issued: 09/04/1990
• Est. Priority Date: 11/10/1987
• Status: Expired due to Term

• Current Assignee: Echelon Systems Corp.
• Original Assignee: Echelon Systems Corp.
• Inventors: Sander, Wendell B., Twitty, William B.
• Primary Examiner(s): Olms, Douglas W.
• Assistant Examiner(s): Marcelo, Melvin
• Application Number:
  US07/268,942
• Time in Patent Office: 665 Days
• Field of Search: 370/94, 370/60, 370/85, 370/89, 370/85.1, 370/85.9, 370/85.13, 370/94.1, 340/825.5, 340/825.51, 340/825.52, 371/33
• US Class Current: 370/398
• CPC Class Codes: G08C 15/00 Arrangements characterised by the use of multiplexing for the transmission of a plurality of signals over a common path
• CPC Class Codes: H02J 13/00007 using the power network as support for the transmission
• CPC Class Codes: H02J 13/00028 involving the use of Internet protocols
• CPC Class Codes: H05B 47/155 Coordinated control of two or more light sources
• CPC Class Codes: Y02B 20/40 Control techniques providing energy savings, e.g. smart controller or presence detection
• CPC Class Codes: Y02B 70/30 Systems integrating technologies related to power network operation and communication or information technologies for improving the carbon footprint of the management of residential or tertiary loads, i.e. smart grids as climate change mitigation technology in the buildings sector, including also the last stages of power distribution and the control, monitoring or operating management systems at local level
• CPC Class Codes: Y04S 20/246 the system involving the remote operation of lamps or lighting equipment

Abstract

A network for sensing, communicating and controlling where a plurality of cells communicate in the network through packets. A first cell transmits a sequence number and a retransmit flag with the messages. The messages are acknowledged by a second cell if the sequence number is different that the previously received sequence number. If the sequence number is the same, the second cell acknowledges the message only if the retransmit flag indicates the message is being retransmitted by the first cell. The second cell takes action on the message only if the sequence number is different than the previously received sequence number.

Claims

1. In a network for sensing, communicating and controlling where said network includes at least a first and a second media, an improvement comprising:

a first plurality of cells coupled to said first media;

a second plurality of cells coupled to said second media;

a third cell coupled to both said first and second media;

at last one of said first cells and one of said second cells having a common group identification number and being assigned a group function for said group, said group function being a common task for sensing, communicating and controlling carried out by said cells in said group identified by said common group identification number;

said third cell having said common group identification number for repeating messages broadcast between said cells having said common group identification number;

whereby sensing and control over a network having a plurality of media is achieved.

2. The improvement defined by claim 1 wherein said third cell rebroadcasts said group messages onto both said first and second media.

3. The improvement defined by claims 1 or 2 in which said first, second and third cells are each assigned a different member number in said group, one of said numbers being stored in each of said first, second and third cells.

4. The improvement defined by claim 1 in which said third cell is programmed to recognize messages being transmitted between the ones of said cells having said common group identification number.

5. In a network for sensing, communicating and controlling where a plurality of cells are coupled to said network, said cells communicating with one another with packets containing messages, an improvement comprising the steps of;

transmitting by a first cells a sequence number and a retransmission flag with said messages, said retransmission flag indicating whether the message is being retransmitted by said first cell;

acknowledging one of said packets by a second cell if said sequence number in said packet is different than the previously received sequence number, and,

if said sequence number is the same as said previously received sequence number, acknowledging said first cell only if said retransmission flag in said packet indicates that said packet has been retransmitted by said first cell,

whereby unnecessary acknowledgements to packets are prevented.

6. The method defined by claim 5 wherein said second cell takes action on said message only if the sequence number is different than said previously received sequence number.

7. In a method for sensing, communicating and controlling where a plurality of cells are coupled to said network, said cells communicating with one another with packets containing messages, an improvement comprising the steps of;

forming said cells into groups, each one of said groups being assigned a group identification number and each one of said cells in said group being assigned a group member number, each group being formed to carry out a group task of sensing, communicating and controlling;

transmitting by a first cell in a first one of said groups a sequence number and a retransmission flag with said messages, said retransmission flag indicating whether the message is being retransmitted by said first cell;

acknowledging one of said packets by a second cell in said first group if said sequence number in said packet is different than the previously received sequence number, and,

if said sequence number is the same as said previously received sequence number, acknowledging said first cell only if said retransmission flag in said packet indicates that said packet has been retransmitted by said first cell,

whereby unnecessary acknowledgements to packets are prevented.

8. The method defined by claim 7 wherein said second cell takes action on said message only if the sequence number is different than said previously received sequence number.