TOPOLOGY MAINTENANCE AND DISCOVERY FACILITY FOR DOWNHOLE NETWORKS

• US 20090189777A1
• Filed: 01/25/2008
• Published: 07/30/2009
• Est. Priority Date: 01/25/2008
• Status: Active Grant

• Current Assignee: IntelliServ, LLC (NOV, Inc.)
• Original Assignee: IntelliServ, LLC (NOV, Inc.)
• Inventors: Johnson, Monte, Stillings, Mark
• Granted Patent: US 7,668,117 B2
• Time in Patent Office: Days
• US Class Current: 340/853.700
• CPC Class Codes: E21B 47/12 Means for transmitting measuring-signals or control signals from the well to the surface, or from the surface to the well, e.g. for logging while drilling
• CPC Class Codes: G01V 11/002 Details, e.g. power supply systems for logging instruments, transmitting or recording data, specially adapted for well logging, also if the prospecting method is irrelevant means for transmitting well survey signals E21B47/12; signal transmission systems in general G08C; transmission in general H04B

Abstract

An apparatus and method for discovering and monitoring a collection of nodes in a downhole network may include receiving data packets originating from several downhole nodes. These packets may be read to extract a unique identifier and hop count for each of the nodes. This information may then be used to create entries in a network topology table corresponding to each of the downhole nodes. Each entry may contain unique identifier identifying the respective node and a hop count identifying a location of the node within the downhole network. The apparatus and method may further include modifying one or more entries in the topology table having conflicting hop counts to ensure that the hop counts of each entry are unique.

Claims

1. A method to discover and monitor a collection of nodes in a downhole:

network, the method comprising;

receiving a first data packet originating from a first downhole node;

reading, from the first packet, a first unique identifier and a first hop count associated with the first downhole node;

creating a first entry in a network topology table corresponding to the first downhole node and storing the first unique identifier and the first hop count;

receiving, after the first data packet, a second data packet originating from a second downhole node;

reading, from the second packet, a second unique identifier and a second hop count associated with the second downhole node;

creating a second entry in the network topology table corresponding to the second downhole node and storing the second unique identifier and the second hop count; and

modifying the first entry in the event the second hop count conflicts with the first hop count.

2. The method of claim 1, wherein modifying the first entry comprises deleting the first entry from the network topology table.

3. The method of claim 1, further comprising storing a status indicator for each of the first and second entries, each status indicator indicating an operating status of the first and second nodes, respectively.

4. The method of claim 3, wherein modifying the first entry comprises modifying the status indicator of the first entry.

5. The method of claim 3, wherein the status indicator designates that a node is at least one of active and inactive.

6. The method of claim 3, wherein the status indicator designates that a node'"'"'s operating status is at least one of expected and unexpected.

7. The method of claim 3, further comprising storing a timestamp for each of the first and second entries, each timestamp indicating the last time a data packet was received from the first and second nodes, respectively.

8. The method of claim 7, further comprising modifying a status indicator in the event the age of a corresponding timestamp exceeds a selected threshold.

9. The method of claim 1, wherein the first and second unique identifiers are globally unique.

10. The method of claim 1, wherein the first and second unique identifiers are unique within a downhole network.

11. A computer-readable medium storing a program of computer-executable instructions to perform operations to discover and monitor a collection of nodes in a downhole network, the operations comprising:

receiving a first data packet originating from a first downhole node;

reading, from the first packet, a first unique identifier and a first hop count associated with the first downhole node;

creating a first entry in a network topology table corresponding to the first downhole node and storing the first unique identifier and the first hop count;

receiving, after the first data packet, a second data packet originating from a second downhole node;

reading, from the second packet, a second unique identifier and a second hop count associated with the second downhole node;

creating a second entry in the network topology table corresponding to the second downhole node and storing the second unique identifier and the second hop count; and

modifying the first entry in the event the second hop count conflicts with the first hop count.

12. The computer-readable medium of claim 11, wherein modifying the first entry comprises deleting the first entry from the network topology table.

13. The computer-readable medium of claim 11, further comprising storing a status indicator for each of the first and second entries, each status indicator indicating an operating status of the first and second nodes, respectively.

14. The computer-readable medium of claim 13, wherein modifying the first entry comprises modifying the status indicator of the first entry.

15. The computer-readable medium of claim 13, wherein the status indicator designates that a node is at least one of active and inactive.

16. The computer-readable medium of claim 13, wherein the status indicator designates that a node'"'"'s operating status is at least one of expected or unexpected.

17. The computer-readable medium of claim 13, further comprising storing a timestamp for each of the first and second entries, each timestamp indicating the last time a data packet was received from the first and second nodes, respectively.

18. The computer-readable medium of claim 17, further comprising modifying a status indicator in the event the age of a corresponding timestamp exceeds a selected threshold.

19. The computer-readable medium of claim 11, wherein the first and second unique identifiers are at least one of globally unique and unique within a downhole network.

20. An apparatus to discover and monitor a collection of nodes in a downhole network, the apparatus comprising a machine-readable medium storing executable and operational data structures, the data structures comprising:

a network topology table maintained to monitor a plurality of nodes in a downhole network, the network topology table comprising a plurality of entries, each entry storing a unique identifier identifying a node and hop count associated with the node; and

the network topology table being further configured such that no two entries, representing active nodes, have the same hop count.

21. The apparatus of claim 20, each entry further configured to store a status indicator identifying an operating status of each node.

22. The apparatus of claim 21, wherein the status indicator designates that a node is at least one of active and inactive.

23. The apparatus of claim 21, wherein the status indicator designates that a node'"'"'s operating status is at least one of expected or unexpected.

24. The apparatus of claim 20, each entry further configured to store a timestamp indicating the last time a data packet was received from a node associated with the entry.

25. The apparatus of claim 20, wherein the unique identifier is at least one of globally unique and unique within the downhole network.

26. A system comprising:

a downhole network comprising a plurality of network nodes positioned along a drill string;

a network topology table maintained to monitor the plurality of network nodes, the network topology table storing an operating status associated with at least one of the network nodes; and

the network topology table further configured to designate whether the operating status is at least one of expected and unexpected.

27. The system of claim 26, further comprising an external input used to determine whether the operating status is at least one of expected and unexpected.

28. The system of claim 27, wherein the external input comprises at least one data item selected from the Wellsite Information Transfer Specification (WITS).

29. The system of claim 27, wherein the external input comprises at least one of operator input, sensor data, and pattern recognition data.

30. The system of claim 26, wherein the network topology table is further configured to store a unique identifier and hop count associated with each node.

31. The system of claim 30, wherein each of the plurality of nodes has a unique hop count.

32. A method comprising:

providing a downhole network comprising a plurality of network nodes positioned along a drill string;

monitoring an operating status associated with at least one of the network nodes; and

designating whether the operating status is at least one of expected and unexpected.

33. The method of claim 32, further comprising utilizing an external input to determine whether the operating status is at least one of expected and unexpected.

34. The method of claim 33, wherein utilizing an external input comprises utilizing at least one data item selected from the Wellsite Information Transfer Specification (WITS).

35. The method of claim 33, wherein utilizing an external input comprises utilizing at least one of operator input, sensor data, and pattern recognition data.

36. The method of claim 32, wherein the network topology table is further configured to store a unique identifier and hop count associated with each node.

37. The method of claim 36, wherein each of the plurality of nodes has a unique hop count.