Method and apparatus for configuring permanent virtual connection (PVC) information stored on network devices in an ATM network logically configured with subnetworks

• US 6,700,890 B1
• Filed: 12/22/1997
• Issued: 03/02/2004
• Est. Priority Date: 12/22/1997
• Status: Expired due to Term

• Current Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Original Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Inventors: Lee, Gabriel, Langley, David
• Primary Examiner(s): Thompson, Marc D.
• Assistant Examiner(s): Prieto, Beatriz
• Application Number:
  US08/996,118
• Time in Patent Office: 2,262 Days
• Field of Search: 709/218, 709/220, 709/221, 709/223, 709/224, 709/227, 709/228, 709/242, 370/254, 370/393, 370/396, 370/225
• US Class Current: 370/395.31
• CPC Class Codes: H04L 12/5601 Transfer mode dependent, e.g. ATM
• CPC Class Codes: H04L 2012/5626 Network management, e.g. Intelligent nets
• CPC Class Codes: H04L 41/0213 Standardised network management protocols, e.g. simple network management protocol [SNMP]
• CPC Class Codes: H04L 41/0816 the condition being an adaptation, e.g. in response to network events
• CPC Class Codes: H04L 41/0853 by actively collecting configuration information or by backing up configuration information
• CPC Class Codes: H04L 41/0856 by backing up or archiving configuration information
• CPC Class Codes: H04L 41/0889 Techniques to speed-up the configuration process
• CPC Class Codes: H04L 41/0895 Configuration of virtualised networks or elements, e.g. virtualised network function or OpenFlow elements
• CPC Class Codes: H04L 49/1553 Interconnection of ATM switching modules, e.g. ATM switching fabrics

Abstract

A method and apparatus retrieves and stores configuration information for network endpoint devices from other devices in the network, such as a switch adjacent to the endpoint device. When the endpoint device establishes a connection with the network, it generates a sequence of SNMP getnext commands using the ILMI interface to obtain the configuration information from the network device. If the network device sends a trap to the endpoint device indicating a change has been made to the configuration parameters stored in the network device for a PVC, a series of SNMP getrequest commands are made using the ILMI interface to retrieve the configuration information for that PVC from the network device. If the endpoint device detects an interruption in communication with the network device, the endpoint device discards the information retrieved previously.

Claims

1. A method of retrieving Permanent Virtual Circuit (PVC) configuration information from a network device in a communications network, wherein the PVC configuration information specifies one or more PVCs defined for the network device, the method comprising the computer-implemented steps of:

generating and providing to the network device a request for PVC configuration information stored in the network device;

receiving, over a physical interface logically configured into a logical main interface and a plurality of logical sub-interfaces, a message containing both the PVC configuration information stored in the network device and a Virtual Path Identifier (VPI), wherein the VPI and a VCI uniquely identify a PVC associated with the PVC configuration information;

comparing the VPI from the message to a first logical sub-interface number of a first logical sub-interface from the plurality of logical sub-interfaces;

if the VPI from the message matches the first logical sub-interface number of the first logical sub-interface, then causing the PVC configuration information from the message to be selectively stored into a first portion of a PVC configuration information storage that is designated for the first logical sub-interface; and

if the VPI from the message does not match the first logical sub-interface number of the first logical sub-interface, then causing the PVC configuration information from the message to be selectively stored into a second portion of the PVC configuration information storage that is designated for the logical main interface.

2. The method as recited in claim 1, further comprising the computer-implemented step of if the VPI from the message does not match the first logical sub-interface number of the first logical sub-interface, then

comparing the VPI from the message to a second logical sub-interface number of a second logical sub-interface from the plurality of logical sub-interfaces; and

if the VPI from the message matches the second logical sub-interface number of the second logical sub-interface, then causing the PVC configuration information from the message to be selectively stored into a second portion of the PVC configuration information storage that is designated for the second logical sub-interface.

3. The method as recited in claim 1, further comprising the computer-implemented steps of:

generating and providing to the network device a second request for PVC configuration information stored in the network device;

receiving, over the physical interface logically configured into the plurality of logical sub-interfaces, a second message containing both updated PVC configuration information stored in the network device and the VPI;

comparing the VPI from the second message to the first logical sub-interface number of the first logical sub-interface from the plurality of logical sub-interfaces; and

if the VPI from the second message matches the first logical sub-interface number of the first logical sub-interface, then causing the updated PVC configuration information from the second message to be selectively stored into the first portion of a PVC configuration information storage that is designated for the first logical sub-interface in a manner that indicates that the updated PVC configuration information is the most recent PVC configuration information for the first logical sub-interface received from the network device.

4. The method as recited in claim 1, further comprising the computer-implemented steps of:

formatting the request for PVC configuration information stored in the network device into a request in a first format for PVC configuration information stored in the network device; and

segmenting the request in the first format into a plurality of formatted request segments.

5. The method as recited in claim 4, wherein the first format is SNMP.

6. The method as recited in claim 4, wherein the first format is AAL5.

7. The method as recited in claim 4, wherein at least one of the plurality of formatted request segments comprises an ATM cell.

8. The method as recited in claim 4, wherein the request includes an ILMI getrequest command in SNMP format.

9. The method as recited in claim 1, wherein the request includes an ILMI getnext command in SNMP format.

10. A computer-readable medium for retrieving Permanent Virtual Circuit (PVC) configuration information from a network device in a communications network, wherein the PVC configuration information specifies one or more PVCs defined for the network device, the computer-readable medium carrying one or more sequences of instructions which, when executed by one or more processors, cause the one or more processors to perform the steps of:

generating and providing to the network device a request for PVC configuration information stored in the network device;

receiving, over a physical interface logically configured into a logical main interface and a plurality of logical sub-interfaces, a message containing both the PVC configuration information stored in the network device and a Virtual Path Identifier (VPI), wherein the VPI and a VCI uniquely identify a PVC associated with the PVC configuration information;

comparing the VPI from the message to a first logical sub-interface number of a first logical sub-interface from the plurality of logical sub-interfaces;

if the VPI from the message matches the first logical sub-interface number of the first logical sub-interface, then causing the PVC configuration information from the message to be selectively stored into a first portion of a PVC configuration information storage that is designated for the first logical sub-interface; and

if the VPI from the message does not match the first logical sub-interface number of the fist logical sub-interface, then causing the PVC configuration information from the message to be selectively stored into a second portion of the PVC configuration information storage that is designated for the logical main interface.

11. The computer-readable medium as recited in claim 10, further comprising one or more sequences of additional instructions which, when executed by the one or more processors, cause the one or more processors to perform the computer-implemented step of if the VPI from the message does not match the first logical sub-interface number of the first logical sub-interface, then

comparing the VPI from the message to a second logical sub-interface number of a second logical sub-interface from the plurality of logical sub-interfaces; and

if the VPI from the message matches the second logical sub-interface number of the second logical sub-interface, then causing the PVC configuration information from the message to be selectively stored into a second portion of the PVC configuration information storage that is designated for the second logical sub-interface.

12. The computer-readable medium as recited in claim 10, further comprising one or more sequences of additional instructions which, when executed by the one or more processors, cause the one or more processors to perform the computer-implemented steps of:

generating and providing to the network device a second request for PVC configuration information stored in the network device;

receiving, over the physical interface logically configured into the plurality of logical sub-interfaces, a second message containing both updated PVC configuration information stored in the network device and the VPI;

comparing the VPI from the second message to the first logical sub-interface number of the first logical sub-interface from the plurality of logical sub-interfaces; and

if the VPI from the second message matches the first logical sub-interface number of the first logical sub-interface, then causing the updated PVC configuration information from the second message to be selectively stored into the first portion of a PVC configuration information storage that is designated for the first logical sub-interface in a manner that indicates that the updated PVC configuration information is the most recent PVC configuration information for the first logical sub-interface received from the network device.

13. The computer-readable medium as recited in claim 10, further comprising one or more sequences of additional instructions which, when executed by the one or more processors, cause the one or more processors to perform the computer-implemented steps of:

formatting the request for PVC configuration information stored in the network device into a request in a first format for PVC configuration information stored in the network device; and

segmenting the request in the first format into a plurality of formatted request segments.

14. The computer-readable medium as recited in claim 13, wherein the first format is SNMP.

15. The computer-readable medium as recited in claim 13, wherein the first format is AAL5.

16. The computer-readable medium as recited in claim 13, wherein at least one of the plurality of formatted request segments comprises an ATM cell.

17. The computer-readable medium as recited in claim 10, wherein the request includes an ILMI getrequest command in SNMP format.

18. The computer-readable medium as recited in claim 10, wherein the request includes an ILMI getnext command in SNMP format.

19. An apparatus for retrieving Permanent Virtual Circuit (PVC) configuration information from a network device in a communications network, wherein the PVC configuration information specifies one or more PVCs defined for the network device, the apparatus comprising a memory carrying one or more sequences of instructions which, when executed by one or more processors, cause the one or more processors to perform the steps of:

generating and providing to the network device a request for PVC configuration information stored in the network device;

receiving, over a physical interface logically configured into a logical main interface and a plurality of logical sub-interfaces, a message containing both the PVC configuration information stored in the network device and a Virtual Path Identifier (VPI), wherein the VPI and a VCI uniquely identify a PVC associated with the PVC configuration information;

comparing the VPI from the message to a first logical sub-interface number of a first logical sub-interface from the plurality of logical sub-interfaces;

if the VPI from the message matches the first logical sub-interface number of the first logical sub-interface, then causing the PVC configuration information from the message to be selectively stored into a first portion of a PVC configuration information storage that is designated for the first logical sub-interface; and

if the VPI from the message does not match the first logical sub-interface number of the fist logical sub-interface then causing the PVC configuration information from the message to be selectively stored into a second portion of the PVC configuration information storage that is designated for the logical main interface.

20. The apparatus as recited in claim 19, wherein the memory further comprises one or more sequences of additional instructions which, when executed by the one or more processors, cause the one or more processors to perform the computer-implemented step of if the VPI from the message does not match the first logical sub-interface number of the first logical sub-interface, then

comparing the VPI from the message to a second logical sub-interface number of a second logical sub-interface from the plurality of logical sub-interfaces; and

if the VPI from the message matches the second logical sub-interface number of the second logical sub-interface, then causing the PVC configuration information from the message to be selectively stored into a second portion of the PVC configuration information storage that is designated for the second logical sub-interface.

21. The apparatus as recited in claim 19, wherein the memory further comprises one or more sequences of additional instructions which, when executed by the one or more processors, cause the one or more processors to perform the computer-implemented steps of:

generating and providing to the network device a second request for PVC configuration information stored in the network device;

receiving, over the physical interface logically configured into the plurality of logical sub-interfaces, a second message containing both updated PVC configuration information stored in the network device and the VPI;

comparing the VPI from the second message to the first logical sub-interface number of the first logical sub-interface from the plurality of logical sub-interfaces; and

if the VPI from the second message matches the first logical sub-interface number of the first logical sub-interface, then causing the updated PVC configuration information from the second message to be selectively stored into the first portion of a PVC configuration information storage that is designated for the first logical sub-interface in a manner that indicates that the updated PVC configuration information is the most recent PVC configuration information for the first logical sub-interface received from the network device.

22. The apparatus as recited in claim 19, wherein the memory further comprises one or more sequences of additional instructions which, when executed by the one or more processors, cause the one or more processors to perform the computer-implemented steps of:

formatting the request for PVC configuration information stored in the network device into a request in a first format for PVC configuration information stored in the network device; and

segmenting the request in the first format into a plurality of formatted request segments.

23. The apparatus as recited in claim 22, wherein the first format is SNMP.

24. The apparatus as recited in claim 22, wherein the first format is AAL5.

25. The apparatus as recited in claim 22, wherein at least one of the plurality of formatted request segments comprises an ATM cell.

26. The apparatus as recited in claim 19, wherein the request includes an ILMI getrequest command in SNMP format.

27. The apparatus as recited in claim 19, wherein the request includes an ILMI getnext command in SNMP format.