Unsynchronous mode brother's keeper bus guardian for a ring networks

• US 7,649,835 B2
• Filed: 11/19/2004
• Issued: 01/19/2010
• Est. Priority Date: 11/19/2003
• Status: Expired due to Fees

• Current Assignee: Honeywell International Inc.
• Original Assignee: Honeywell International Inc.
• Inventors: Driscoll, Kevin R., Hall, Brendan, Paulitsch, Michael
• Primary Examiner(s): Patel; Jayanti K
• Assistant Examiner(s): ZHU, BO HUI ALVIN
• Application Number:
  US10/993,931
• Publication Number:
  US 20050135277A1
• Time in Patent Office: 1,887 Days
• Field of Search: 370216-228, 370/248, 370/258, 370404-406
• US Class Current: 370/216
• CPC Class Codes: H04L 12/43 with synchronous transmission, e.g. time division multiplex [TDM], slotted rings
• CPC Class Codes: H04L 12/437 Ring fault isolation or reconfiguration for SDH/SONET ring networks H04J3/085

Abstract

In one embodiment, a node comprises an interface to communicatively couple the node to a first channel. The first channel communicatively couples the node to a first neighbor node and a first neighbor'"'"'s neighbor node in a first direction. When the node is operating in an unsynchronized mode: the node relays, along the first channel, for a relay period, data received from the first neighbor node that was sourced from that first neighbor node and, after relaying the data received from the first neighbor node that was sourced from that first neighbor node and for a block period, the node blocks data received from the first neighbor while the node relays, along the first channel, data received from the first neighbor'"'"'s neighbor node.

Claims

1. A node comprising:

an interface to communicatively couple the node to a first channel;

wherein the first channel communicatively couples the node to a first neighbor node and a first neighbor'"'"'s neighbor node in a first direction; and

when the node is operating in an unsynchronized mode;

determines if data received on the first channel from the first neighbor node was sourced from that first neighbor node; and

if data received on the first channel from the first neighbor node was sourced from that first neighbor node;

the node relays, along the first channel, for a relay period, the data received from the first neighbor node that was sourced from that first neighbor node; and

after relaying the data received from the first neighbor node that was sourced from that first neighbor node and for a block period, the node blocks data received from the first neighbor while the node relays, along the first channel, data received from the first neighbor'"'"'s neighbor node.

2. The node of claim 1, wherein the first channel communicatively couples the node to a second neighbor node and to a second neighbor'"'"'s neighbor node in a second direction.

3. The node of claim 2, wherein the first channel comprises:

a first direct link that communicatively couples the node to the first neighbor node via the first channel;

a first skip link that communicatively couples the node to the first neighbor'"'"'s neighbor node via the first channel;

a second direct link that communicatively couples the node to the second neighbor node via the first channel; and

a second skip link that communicatively couples the node to the second neighbor'"'"'s neighbor node via the first channel.

4. The node of claim 2, further comprising an interface to communicatively couple the node to a second channel, wherein the second channel communicatively couples the node to the second neighbor node and the second neighbor'"'"'s neighbor in the second direction and to the first neighbor node and the first neighbor'"'"'s neighbor in the first direction.

5. The node of claim 4, wherein when the node is operating in the unsynchronized mode:

the node relays, along the second channel, for the relay period, data received from the second neighbor node that was sourced from that second neighbor node; and

after relaying the data received from the second neighbor node that was sourced from that second neighbor node and for a block period, the node blocks data received from the second neighbor while the node relays, along the second channel, data received from the second neighbor'"'"'s neighbor node.

6. The node of claim 5, wherein the node relays data along the second channel by relaying the data along the second channel to the first neighbor node and the first neighbor'"'"'s neighbor node.

7. The node of claim 4, wherein the node, when operating in the unsynchronized mode, relays, along the second channel, data received from the second neighbor node that was not sourced from the second neighbor node.

8. The node of claim 4, wherein the second channel comprises a ring.

9. The node of claim 2, wherein the node relays data along the first channel by relaying the data along the first channel to the second neighbor node and the second neighbor'"'"'s neighbor node.

10. The node of claim 1, wherein the node, when operating in the unsynchronized mode, relays, along the first channel, data received from the first neighbor node that was not sourced from the first neighbor node.

11. The node of claim 1, wherein the relay period comprises at least an amount of time long enough for a cold start message to be received at each of a plurality of nodes that communicate over the first channel.

12. The node of claim 1, wherein the block period comprises at least an amount of time long enough for another node to initiate the transmission of a cold start message on the first channel.

13. The node of claim 1, wherein the node, to determine if data received from the first neighbor node was sourced from the first neighbor node, compares the data received from the first neighbor node to data received from the first neighbor'"'"'s neighbor node, wherein the data received from the first neighbor node was sourced by the first neighbor node if the data received from the first neighbor node is not identical to the data received from the first neighbor'"'"'s neighbor node.

14. The node of claim 1, wherein, upon waking up, the node does not relay any data for an initial block period.

15. The node of claim 14, wherein the initial block period comprises an amount of time at least as long as one inter-frame gap.

16. The node of claim 1, wherein the channel comprises a ring.

17. A method of communicating data by a node that is communicatively coupled to a first channel that communicatively couples the node to a first neighbor node and a first neighbor'"'"'s neighbor node in a first direction, the method comprising:

when the node operates in an unsynchronized mode;

determining if data received on the first channel from the first neighbor node was sourced from that first neighbor node; and

if data received on the first channel from the first neighbor node was sourced from that first neighbor node;

relaying, along the first channel, for a relay period the data received from the first neighbor node that was sourced from that first neighbor node; and

after relaying the data received from the first neighbor node that was sourced from the first neighbor node, for a block period, blocking data received from the first neighbor while relaying, along the first channel, data received from the first neighbor'"'"'s neighbor node.

18. The method of claim 17, wherein the first channel communicatively couples the node to a second neighbor node and to a second neighbor'"'"'s neighbor node in a second direction.

19. The method of claim 18, wherein the node is communicatively coupled to a second channel that communicatively couples the node to the second neighbor node and the second neighbor'"'"'s neighbor in the second direction and to the first neighbor node and the first neighbor'"'"'s neighbor in the first direction.

20. The method of claim 19, further comprising, when the node is operating in the unsynchronized mode:

relaying, along the second channel, for the relay period, data received from the second neighbor node that was sourced from that second neighbor node; and

after relaying the data received from the second neighbor node that was sourced from that second neighbor node and for a block period, blocking data received from the second neighbor while relaying, along the second channel, data received from the second neighbor'"'"'s neighbor node.

21. The method of claim 20, wherein the node relays data along the second channel by relaying the data along the second channel to the first neighbor node and the first neighbor'"'"'s neighbor node.

22. The method of claim 19, further comprising, when the node is operating in the unsynchronized mode, relaying, along the second channel, data received from the second neighbor node that was not sourced from the second neighbor node.

23. The method of claim 19, wherein the second channel comprises a ring.

24. The method of claim 18, wherein the node relays data along the first channel by relaying the data along the first channel to the second neighbor node and the second neighbor'"'"'s neighbor node.

25. The method of claim 17, further comprising, when the node is operating in the unsynchronized mode, relaying, along the first channel, data received from the first neighbor node that was not sourced from the first neighbor node.

26. The method of claim 17, wherein the relay period comprises at least an amount of time long enough for a cold start message to be received at each of a plurality of nodes that communicate over the first channel.

27. The method of claim 17, wherein the block period comprises at least an amount of time long enough for another node to initiate the transmission of a cold start message on the first channel.

28. The method of claim 17, further comprising, when the node is operating in the unsynchronized mode, determining if data received from the first neighbor node was sourced from the first neighbor node by comparing the data received from the first neighbor node to data received from the first neighbor'"'"'s neighbor node, wherein the data received from the first neighbor node was sourced by the first neighbor node if the data received from the first neighbor node is not identical to the data received from the first neighbor'"'"'s neighbor node.

29. The method of claim 17, further comprising wherein, upon waking up, blocking any data received from the first neighbor node and the first neighbor'"'"'s node for an initial block period.

30. The method of claim 29, wherein the initial block period comprises an amount of time at least as long as one inter-frame gap.

31. The method of claim 17, wherein the first channel comprises a ring.

32. A network comprising:

a plurality of nodes that are communicatively coupled to one another over a first channel;

wherein the channel communicatively couples each node to a first neighbor node and a first neighbor'"'"'s neighbor node in a first direction; and

wherein each node, when operating in an unsynchronized mode;

determines if data received at that node on the first channel from the first neighbor node of that node was sourced from that first neighbor node; and

if data received at that node on the first channel from the first neighbor node of that node was sourced from that first neighbor node;

relays, along the first channel, for a relay period, the data received from the first neighbor node of that node, that was sourced from that first neighbor node; and

after relaying the data received from that first neighbor node that was sourced from that first neighbor node, for a block period, blocks data received from that first neighbor while that node relays, along the first channel, data received from the first neighbor'"'"'s neighbor node of that node.

33. The network of claim 32, wherein the first channel communicatively couples the node to a second neighbor node and to a second neighbor'"'"'s neighbor node in a second direction.

34. The network of claim 33, wherein each of the plurality of nodes is communicatively coupled to a second channel, wherein the second channel communicatively couples each node to the second neighbor node of that node and the second neighbor'"'"'s neighbor of that node in the second direction and to the first neighbor node of that node and the first neighbor'"'"'s neighbor of that node in the first direction.

35. The network of claim 34, wherein each node, when operating in the unsynchronized mode:

relays, along the second channel, for the relay period, data received from the second neighbor node of that node that was sourced from that second neighbor node; and

after relaying the data received from that second neighbor node that was sourced from that second neighbor node, for the block period, blocks data received from that second neighbor while that node relays, along the second channel, data received from the second neighbor'"'"'s neighbor node of that node.

36. The network of claim 35, wherein each node relays data along the second channel by relaying the data along the second channel to the first neighbor node and the first neighbor'"'"'s neighbor node.

37. The network of claim 34, wherein each node, when operating in the unsynchronized mode, relays, along the second channel, data received from the second neighbor node of that node that was not sourced from that second neighbor node.

38. The network of claim 34, wherein the second channel comprises a ring.

39. The network of claim 33, wherein each node relays data along the first channel by relaying the data along the first channel to the second neighbor node of that node and the second neighbor'"'"'s neighbor node of that node.

40. The network of claim 32, wherein each node, when operating in the unsynchronized mode, relays, along the first channel, data received from the first neighbor node of that node that was not sourced from that first neighbor node.

41. The network of claim 32, wherein the relay period comprises at least an amount of time long enough for a cold start message to be received at each of a plurality of nodes that communicate over the first channel.

42. The network of claim 32, wherein the block period comprises at least an amount of time long enough for another node to initiate the transmission of a cold start message on the first channel.

43. The network of claim 32, wherein each node, to determine if data received from the first neighbor node of that node was sourced from that first neighbor node, compares the data received from that first neighbor node to data received from the first neighbor'"'"'s neighbor node of that node, wherein the data received from that first neighbor node was sourced by that first neighbor node if the data received from that first neighbor node is not identical to the data received from that first neighbor'"'"'s neighbor node.

44. The network of claim 32, wherein, upon waking up, each node does not relay any data for an initial block period.

45. The network of claim 44, wherein the initial block period comprises an amount of time at least as long as one inter-frame gap.

46. The network of claim 32, wherein the channel comprises a ring.

47. A node comprising:

means for communicatively coupling the node to a channel, where the channel communicatively couples the node to a first neighbor node and a first neighbor'"'"'s neighbor node in a first direction;

means for operating in unsynchronized mode comprising that comprise;

means for determining if data received on the first channel from the first neighbor node was sourced from that first neighbor node; and

means for, if data received on the first channel from the first neighbor node was sourced from that first neighbor node;

relaying, along the first channel, for a relay period, data received from the first neighbor node that was sourced from that first neighbor node; and

blocking data received from the first neighbor while relaying, along the first channel, data received from the first neighbor'"'"'s neighbor node for a block period, after relaying the data received from the first neighbor node that was sourced from the first neighbor node.