Method of configuring and managing a network

• US 7,272,635 B1
• Filed: 10/04/2002
• Issued: 09/18/2007
• Est. Priority Date: 10/04/2002
• Status: Active Grant

• Current Assignee: Analog Devices BV (Analog Devices, Inc.)
• Original Assignee: Domosys Corporation (Analog Devices, Inc.)
• Inventors: Vachon, Patrick, Longtin, Pierre, Pilote, Martin, Baril, Steve
• Primary Examiner(s): Maung; Zarni
• Assistant Examiner(s): Daftuar; Saket K
• Application Number:
  US10/264,784
• Time in Patent Office: 1,810 Days
• Field of Search: 709/208, 709/209, 709/227, 370/222
• US Class Current: 709/208
• CPC Class Codes: H04L 41/0663 Performing the actions predefined by failover planning, e.g. switching to standby network elements
• CPC Class Codes: H04L 41/0806 for initial configuration or provisioning, e.g. plug-and-play
• CPC Class Codes: H04L 45/22 Alternate routing
• CPC Class Codes: H04L 45/28 using route fault recovery
• CPC Class Codes: H04W 40/248 Connectivity information update

Abstract

The network comprises a master node and a plurality of slave nodes. To configure the network, the master node transmits over the network a hailing message at any attenuated level compared to normal communication signals to be transmitted over the network. Upon receiving the hailing message at one of the slave node, a reply message is transmitted, also at an attenuated level. Receiving the reply message at the master node allows it to configure the slave node from which the reply message originated. Also disclosed are a method of managing a network so as to monitor the connections between the slave nodes, and a method of managing a network when a recovery operation is required.

Claims

1. A method of identifying, in a network, a plurality of slave nodes for a master node, said master node configured to transmit a normal communication signal at a first transmission output level, the method comprising:

transmitting a first hailing message from the master node to the plurality of slave nodes, the hailing message being encoded in an analog hailing transmission signal and having a transmission output level that is attenuated compared to the normal communication signal from said master node transmitted over the network;

upon detection of receipt of the hailing message by at least one receiving slave node of the plurality of slave nodes, generating and transmitting a reply message from the receiving slave node that is intended for the master node, the reply message identifying the at least one receiving slave node and being encoded in an analog reply transmission signal having a reply transmission output level that is attenuated compared to the normal communication signal; and

upon the master node receiving the reply message, then identifying the receiving slave node from the reply message and storing in a routing table information indicating that the receiving slave node is a first configured slave node capable of communicating with the master node at said reply transmission output level.

2. The method according to claim 1, further comprising:

attempting to hail remaining unconfigured slave nodes of said plurality of slave nodes by sending an instruction message from the master node to the configured slave node;

upon receiving the instruction message at the configured slave node, transmitting the second hailing message from the configured slave node, the second hailing message being encoded in an analog hailing transmission signal having a transmission output level that is attenuated compared to the normal communication signal output level;

upon receiving the second message at an unconfigured slave node of said remaining unconfigured slave nodes, transmitting by an unconfigured slave node of a reply message to the configured slave node, the reply message being transmitted at an attenuated level compared to the normal communication signal output level;

upon receiving the reply message at the configured slave node, transmitting a post-reply message to the master node containing details of the configured slave node and the unconfigured slave node;

upon receiving the post-reply message at the master node, analyzing the post-reply message to identify the unconfigured slave node and the configured slave node and updating the routing table to indicate that the unconfigured slave node is a second configured slave node capable of communicating with the master node through the first configured slave node; and

after updating the routing table, configuring further messages from the master node destined for the second configured slave node to be sent through the first configured slave node.

3. The method according to claim 1, further comprising:

attempting to validate a connection between the master node and a leaf slave node in the network that is at an end of a communication branch from the master node by generating a ping message at the master node and transmitting the ping message towards the leaf node;

upon receiving the ping message at the leaf slave node, then transmitting a reply message from the leaf node to the master node; and

upon not receiving by the master node of the reply within a time limit, then updating the routing table to indicate that the leaf slave node did not reply.

4. The method according to claim 3, wherein the reply message is transmitted at an attenuated signal level compared to the normal communication signal.

5. The method according to claim 4, wherein the ping message and the reply message are routed through an intermediary slave node in the branch.

6. The method according to claim 3, wherein the ping message is sent when the master node is in an idle state.

7. A method of recovering from a failure in a network having a master node and a plurality of slave nodes, the method comprising:

maintaining a routing table containing information on interconnections among the plurality of slave nodes and reaching areas in the network for the plurality of slave nodes;

upon detection of a failure of a failed node of the plurality of nodes, utilizing the routing table to identify an upstream slave node in the plurality of slave nodes that normally transmits communications from the master node to the failing node, to determine a reaching area for the upstream slave node;

transmitting a recovery message to another slave node of the plurality of slave nodes that has a comparable reaching area to the upstream slave node, the recovery message instructing the another slave node to transmit a hailing message to the failed slave node, the hailing message being encoded in an analog hailing transmission signal having a hailing transmission output level that is attenuated compared to a normal communication signal transmitted over the network; and

upon receiving the hailing message at the failed slave node, then;

transmitting a reply message to the another slave node from the failed slave node, the reply message being transmitted at an attenuated level compared to the normal communication signal;

upon receiving the reply message at the another slave node, transmitting a post-reply message to the master node; and

node receiving the post-reply message at the master node, identifying the failed slave node from which the reply message originated, identifying the another slave node from which the post-reply message originated and updating the routing table to indicate that the failed slave node is capable of communicating through the another slave node.

8. The method according to claim 7, wherein if the reply message is not received at the another slave node within a predetermined time period, then identifying a further slave node that has a comparable reaching area to the upstream slave node and transmitting the hailing message from the further slave node.

9. The method according to claim 8, wherein if the further slave node cannot be identified, then selecting a still further slave node in the network starting from a lowest level in the network and attempting to contact the failed slave node through the still further slave node.

10. The method according to claim 7, wherein the failure of the failed node is signified from an error message generated and sent by the upstream slave node to the master node.

11. The method according to claim 10, wherein the ping message is transmitted at an output level between the transmission output level of the attenuated hailing signal and the output level of the normal communication signal.

12. A master node for communicating with a a plurality of slave nodes over network, the master node comprising:

a transmitter configured to generate and transmit communication signals to said network, said signals having at least a first transmission output level and a second, lower transmission output level;

a receiver configured to receive said communication signals from said network;

a module to generate a normal communication signal to be transmitted from the transmitter at the first transmission output level;

a module to generate a hailing message to be transmitted from the transmitter to the plurality of slave nodes, the hailing message being encoded in an analog hailing transmission having a transmission output level at the second, lower output level that is attenuated compared to the normal communication signal;

a module to monitor for receipt of a reply message from a receiving slave node of the plurality of slave nodes that responds to any hailing message, the reply message being encoded in an analog reply transmission having a transmission output level that is attenuated compared to the normal communication signal; and

a module to identify the receiving slave node from the reply message and to store in a routing table information indicating that the receiving slave node is a configured slave node capable of communicating with the master node.

13. The master node for communicating with a network a plurality of slave nodes as claimed in claim 12, wherein

the module to generate the hailing message;

attempts to hail remaining unconfigured nodes of said plurality of nodes by sending an instruction message from the master node to the configured slave node; and

upon the master node receiving a second message at an unconfigured slave node of said remaining unconfigured nodes, generates a reply message for transmission to the configured slave node, the reply message being transmitted at an attenuated level compared to the normal communication signal; and

the module to identify the receiving slave node from the reply message;

upon the master node receiving a post-reply message, analyzes the post-reply message to identify the unconfigured slave node and the configured slave node and updating the routing table to indicate that the unconfigured slave node is a newly configured slave node capable of communicating with the master node through the configured slave node; and

after updating the routing table, configures further messages from the master node destined for the newly configured slave node to be sent through the configured slave node.

14. The master node for communicating with a network a plurality of slave nodes as claimed in claim 13, further comprising:

a routing table containing information on interconnections among the plurality of slave nodes and reaching areas in the network for the plurality of slave nodes;

a failure analysis module that upon detection of a failure of a failed node of the plurality of nodes;

a. utilizes the table to identify an upstream slave node in the plurality of nodes that normally transmits communications from the master node to the failing node and to determine a reaching area for the upstream slave node;

b. generates a recovery message for transmission to another slave node of the plurality of slave nodes that has a comparable reaching area to the upstream slave node, the recovery message instructing the another slave node to transmit a hailing message to the failed slave node, the hailing message having attenuated transmission level compared to a normal communication signal transmitted over the network; and

c. upon having the hailing message being received at the failed slave node;

generates a reply message for transmission to the another slave node from the failed slave node, the reply message being transmitted at an attenuated level compared to the normal communication signal; and

upon receiving a post-reply message at the master node from the another slave node, identifies the failed slave node from which the reply message originated, identifies the another slave node from which the post-reply message originated and updates the routing table to indicate that the failed slave node is capable of communicating through the another slave node.