Early warning fault identification and isolation system for a two-way cable network

• US 7,594,252 B2
• Filed: 03/01/2005
• Issued: 09/22/2009
• Est. Priority Date: 03/01/2005
• Status: Active Grant

• Current Assignee: Time Warner Cable Enterprises LLC (Charter Communications Incorporated)
• Original Assignee: Time Warner Cable Inc. (Charter Communications Incorporated)
• Inventors: Mandlekar, Amol, Johnson, Keith
• Primary Examiner(s): Beliveau; Scott
• Assistant Examiner(s): TELAN, MICHAEL R
• Application Number:
  US11/069,155
• Publication Number:
  US 20060218609A1
• Time in Patent Office: 1,666 Days
• Field of Search: 725/107, 725/105, 725117-118, 725124-152, 709223-224, 370216-229, 370241-242, 370/244, 370351-430, 370449-454, 714 1- 57
• US Class Current: 725/107
• CPC Class Codes: H04L 41/0659 by isolating or reconfiguring faulty entities
• CPC Class Codes: H04L 43/0811 by checking connectivity
• CPC Class Codes: H04L 43/0817 by checking functioning
• CPC Class Codes: H04N 21/6118 involving cable transmission, e.g. using a cable modem
• CPC Class Codes: H04N 21/6168 involving cable transmission, e.g. using a cable modem
• CPC Class Codes: H04N 21/6338 directed to network
• CPC Class Codes: H04N 21/64322 IP
• CPC Class Codes: H04N 21/6473 Monitoring network processes errors for recovering from a failure of a protocol instance or entity H04L69/40

Abstract

Set top boxes (STBs) connected to the HFC cable network are “pinged” and their responses recorded. The two most responsive STBs in each node of the HFC cable network are identified. The most responsive STB is added to a primary ping list and the next most responsive STB is added to a secondary ping list. The STBs on the primary list are “pinged” and their responses recorded. If an STB on the primary list fails to respond, the secondary STB associated with the node is pinged. If both the primary and secondary STB associated with a node fail to respond to the “ping,” the node is identified as non-responsive. If all of the nodes associated with a modulator (or a demodulator) are identified as non-responsive, the modulator (or demodulator) is identified as “non-responsive.” Additionally, network devices are pinged and their responses noted. Using the responsiveness of nodes and network devices, faults in segments in an HFC cable network can be identified and located.

Claims

1. A method of determining an operational status of a segment of a hybrid fiber coax (HFC) cable network comprising:

accessing a ping datastore to acquire ping data associated with a plurality of set top boxes (STBs) connected to the HFC network through a common node, wherein the ping data comprise for each STB of the plurality of STBs a ratio of a number of ping responses to a number of ping queries;

selecting from the ping data associated with the plurality of STBs a primary STB, wherein the primary STB has the highest ratio of ping responses to ping queries and wherein the primary STB is associated with a primary STB IP address; and

selecting from the ping data associated with the plurality of STBs a secondary STB, wherein the secondary STB has the second highest ratio of ping responses to ping queries and wherein the secondary STB is associated with a secondary STB IP address;

pinging the primary STB IP address;

determining whether a response from the ping is received from the primary STB;

when the response from the ping is received from the primary STB, then setting a primary STB operational status of the primary STB to responsive;

when the response from the ping is not received from the primary STB, pinging the secondary STB IP address;

determining whether a response from the ping is received from the secondary STB;

when the response from the ping is received from the secondary STB, then setting a secondary STB operational status of the secondary STB to responsive and setting a node operational status of the common node to responsive;

when the response from the ping is not received from the secondary STB, then setting the secondary STB operational status of the secondary STB to non-responsive and setting the node operational status of the common node to non-responsive; and

determining an operational status of a network component upstream from the common node based on the node operational status of all nodes serviced by the upstream network component.

2. The method of determining an operational status of a segment of an HFC cable network of claim 1, wherein the method further comprises:

creating a node display string comprising data elements indicative of the node operational status of the common node;

sending the node display string to a display server; and

displaying the data elements indicative of the node operational status of the common node.

3. The method of determining an operational status of a segment of an HFC cable network of claim 1, wherein the upstream network component comprises a demodulator and wherein determining the operational status of a network component upstream from the common node based on the node operational status of all nodes serviced by the upstream network component comprises:

determining the node operational status of nodes associated with the demodulator;

when the node operational status of at least one node associated with the demodulator is responsive, then setting a demodulator operational status of the demodulator to responsive; and

when the node operational status of the nodes associated with the demodulator is non-responsive, then setting the demodulator operational status of the demodulator to non-responsive; and

taking remedial action to repair the demodulator.

4. The method of determining an operational status of a segment of an HFC cable network of claim 3, wherein the method further comprises:

creating a demodulator display string comprising data elements indicative of the demodulator operational status;

sending the demodulator display string to a display server; and

displaying the data elements indicative of the demodulator operational status.

5. The method of determining an operational status of a segment of an HFC cable network of claim 4, wherein the upstream network component comprises a modulator and wherein determining the operational status of a network component upstream from the common node based on the node operational status of all nodes serviced by the upstream network component comprises:

determining the node operational status of nodes associated with the modulator;

when the node operational status of at least one node associated with the modulator is responsive, then setting a modulator operational status of the modulator to responsive;

when the node operational status of the nodes associated with the modulator is non-responsive, then setting the modulator operational status of the modulator to non-responsive; and

taking remedial action to repair the modulator.

6. The method of determining an operational status of a segment of an HFC cable network of claim 5, wherein the method further comprises:

creating a modulator display string comprising data elements indicative of the modulator operational status;

sending the modulator display string to a display server; and

displaying the data elements indicative of the modulator operational status.

7. The method of determining an operational status of a segment of an HFC cable network of claim 1, wherein the method further comprises:

obtaining an IP address of a network component associated with the common node;

pinging the network component IP address;

determining whether a response is received from the network component;

when the response is received from the network component, then setting a component operational status of the network component to responsive;

when the response is not received from the network component, then setting the component operational status of the network component to non-responsive; and

taking remedial action to repair the network component.

8. The method of determining an operational status of a segment of an HFC cable network of claim 7, wherein the network component is selected from the group consisting of an edge device, a router, and a switch.

9. The method of determining an operational status of a segment of an HFC cable network of claim 7, wherein the method further comprises:

creating a network component display string comprising data elements indicative of the component operational status;

sending the network component display string to a display server; and

displaying the data elements indicative of the component operational status.

10. The method of determining an operational status of a segment of an HFC cable network of claim 7, wherein the method further comprises determining an operational status of a component downstream from the common node based on the component operational status of network components downstream from the common node.

11. The method of determining an operational status of a segment of an HFC cable network of claim 1, wherein selecting the primary and secondary STBs based on a measure of ping responses to ping queries further comprises selecting the primary and secondary STBs based on a distance from a hub upstream from the primary and secondary STBs.

12. A system for determining an operational status of a segment of a hybrid fiber coax (HFC) cable network comprising:

a ping list generator, wherein the ping list generator is configured for;

accessing a ping datastore to acquire ping data associated with a plurality of STBs connected to the HFC network through a common node, wherein the ping data comprise for each STB of the plurality of STBs a ratio of a number of ping responses to a number of ping queries;

selecting from the ping data associated with the plurality of STBs a primary STB, wherein the primary STB has the highest ratio of ping responses to ping queries and wherein the primary STB is associated with a primary STB IP address; and

selecting from the ping data associated with the plurality of STBs a secondary STB, wherein the secondary STB has the second highest ratio of ping responses to ping queries and wherein the secondary STB is associated with a secondary STB IP address;

an STB pinger, wherein the STB pinger is configured for;

receiving a ping list from the ping list generator comprising IP addresses associated with STBs;

pinging the IP address of each STB on the ping list;

when a response from the ping is received from an STB associated with a pinged IP address, then setting an STB operational status of the STB as responsive; and

when the response from the ping is not received from the STB associated with the pinged IP address, then setting the STB operational status of the STB as non-responsive;

a results processor, wherein the results processor is configured for;

determining an STB operational status of the primary STB;

when the primary STB operational status is responsive, then setting a node operational status of the common node to responsive;

when the primary STB operational status is non-responsive, then sending the secondary IP address to the STB pinger for pinging;

determining an STB operational status of the secondary STB; and

when the secondary STB operational status is non-responsive, then setting the node operational status of the common node to nonresponsive; and

a final results processor, wherein the final results processor is configured for determining an operational status of a network component upstream from the common node based on the node operational status of all nodes serviced by the upstream network component.

13. The system of claim 12, wherein the final results processor is further configured for:

creating a node display string comprising data elements indicative of the common node operational status; and

sending the node display string to a display server; and

wherein the display server is configured for displaying the data elements indicative of the common node operational status.

14. The system of claim 12, wherein the upstream network component comprises a demodulator and wherein the final results processor is further configured for:

determining the node operational status of nodes associated with the demodulator;

when the node operational status of at least one node associated with the demodulator is responsive, then setting a demodulator operational status of the demodulator to responsive; and

when the node operational status of the nodes associated with the demodulator is non-responsive, then setting the demodulator operational status of the demodulator to non-responsive.

15. The system of claim 14, wherein the final results processor is further configured for:

creating a demodulator display string comprising data elements indicative of the demodulator operational status; and

sending the demodulator display string to a display server; and

wherein the display server comprises instruction for displaying the data elements indicative of the demodulator operational status.

16. The system of claim 12, wherein the upstream network component comprises a modulator and wherein the final results processor is further configured for:

determining the node operational status of nodes associated with the modulator;

when the node operational status of at least one node associated with the modulator is responsive, then setting the modulator operational status of the modulator to responsive; and

when the node operational status of the nodes associated with the modulator is non-responsive, then setting the modulator operational status of the modulator to non-responsive.

17. The system of claim 16, wherein the final results processor is further configured for:

creating a modulator display string comprising data elements indicative of the modulator operational status; and

sending the modulator display string to a display server; and

wherein the display server is configured for displaying the data elements indicative of the modulator operational status.

18. The system of claim 12, wherein the system further comprises a network component pinger, and wherein the network component pinger is configured for:

obtaining an IP address of a network component associated with the common node;

pinging the network component IP address;

determining whether a response is received from the network component;

when the response is received from the network component, then setting a component operational status of the network component to responsive; and

when the response is not received from the network component, then setting the component operational status of the network component to non-responsive.

19. The system of claim 18, wherein the network component is selected from the group consisting of an edge device, a router, and a switch.

20. The system of claim 18, wherein the final results processor is further configured for:

creating a network component display string comprising data elements indicative of the component operational status; and

sending the network component display string to a display server; and

wherein the display is configured for displaying the data elements indicative of the component operational status.

21. The system of claim 18, wherein the final results processor is further configured for determining an operational status of a component downstream from the common node based on the component operational status of network components downstream from the common node.

22. The system of claim 12, wherein the primary and secondary STBs are further selected based on a distance from a hub upstream from the primary and secondary STBs.