Module firmware recovery

• US 6,606,298 B1
• Filed: 06/30/1999
• Issued: 08/12/2003
• Est. Priority Date: 06/30/1999
• Status: Expired due to Term

• Current Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Original Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Inventors: Foltak, Richard
• Primary Examiner(s): VINCENT, DAVID ROBERT
• Application Number:
  US09/346,557
• Time in Patent Office: 1,504 Days
• Field of Search: 370/216, 370/217, 370/218, 370/221, 370/225, 370/241, 370/242, 370/244, 370/245, 370/246, 370/248.9, 370/250, 370/252, 370/359, 370/419, 370/463
• US Class Current: 370/216
• CPC Class Codes: H04L 12/2856 Access arrangements, e.g. Internet access asynchronous transfer mode networks H04L12/5601; broadband local area networks H04L12/2801; optical access or distribution networks H04Q11/0067; access to open networks H04L12/5691; digital subscriber line end-user equipment and bit-level processing of data on a PSTN-based network H04M11/00; home network gateways H04L12/2834; wireless access networks H04W
• CPC Class Codes: H04L 12/2896 Distributed processing, e.g. on line cards
• CPC Class Codes: H04Q 11/0414 Details
• CPC Class Codes: H04Q 2213/13003 Constructional details of switching devices
• CPC Class Codes: H04Q 2213/13093 Personal computer, PC
• CPC Class Codes: H04Q 2213/13103 Memory
• CPC Class Codes: H04Q 2213/13106 Microprocessor, CPU
• CPC Class Codes: H04Q 2213/13107 Control equipment for a part of the connection, distributed control, co-processing
• CPC Class Codes: H04Q 2213/13164 Traffic (registration, measurement,...)
• CPC Class Codes: H04Q 2213/13166 Fault prevention
• CPC Class Codes: H04Q 2213/13167 Redundant apparatus
• CPC Class Codes: H04Q 2213/13196 Connection circuit/link/trunk/junction, bridge, router, gateway
• CPC Class Codes: H04Q 2213/13199 Modem, modulation
• CPC Class Codes: H04Q 2213/13209 ISDN
• CPC Class Codes: H04Q 2213/13213 Counting, timing circuits
• CPC Class Codes: H04Q 2213/1322 PBX
• CPC Class Codes: H04Q 2213/13298 Local loop systems, access network
• CPC Class Codes: H04Q 2213/13299 Bus
• CPC Class Codes: H04Q 2213/13332 Broadband, CATV, dynamic bandwidth allocation
• CPC Class Codes: H04Q 2213/13376 Information service, downloading of information, 0800/0900 services
• CPC Class Codes: H04Q 2213/13389 : LAN, internet
• CPC Class Codes: H04Q 2213/13396 : Signaling in general, in-band signalling

Abstract

A method and apparatus of the present invention includes a network access server (NAS) for use in a communications system utilized by users of telephone, fax, or modem calls, the NAS having more than one processor with a plurality of processors forming a module, each processor for performing various functions by executing code stored in a memory device accessible by the processor wherein either upgrading of the stored code or recovery of one or more of the processors is required. The NAS determines that one or more of the processors of a particular module is ‘bad’, marks the bad processors as being in a ‘Recovery Pending’ state, schedules recovery of the ‘bad’ processor during a window of time defined by a predetermined duration of time in the day during which the communications system is least utilized by the users, disables the particular module so that no calls are processed through the particular module, attempts recovery of the ‘bad’ processor during the window of time and if the step of attempting recovery takes longer than the window of time, stops the recovery and retries recovery during the window of time on the next day.

Claims

1. A method for use in a communications system utilized by users of telephone or modem calls, the communications system having more than one processor with a plurality of processors forming a module, each processor for performing various functions by executing code stored in a memory device, the method for upgrading the stored code for any one of the processors or for recovering one or more processors, comprising:

determining one or more of the processors of a particular module to be ‘

bad’

;

scheduling recovery of the ‘

bad’

processor during a predetermined window of time;

“

busying out”

the particular module so that no calls are processed through the particular module;

attempting recovery of the ‘

bad’

processor during the window of time; and

if the step of attempting recovery takes longer than the window of time, stopping the recovery.

2. A method for use in a communications system as recited in claim 1 wherein during the step of attempting recovery, downloading a particular code to the ‘

bad’

processor and treating the ‘

bad’

processor as operational.

3. A method for use in a communications system as recited in claim 1 wherein the determining step includes waiting a predetermined number of times for calls through the one or more processors to fail prior to the marking step.

4. A method for use in a communications system as recited in claim 1 further including, after the step of determining, marking the bad processors as being in a ‘

Recovery Pending’

state wherein the processors that are in “

Recovery Pending”

cannot accept incoming calls.

5. A method for use in a communications system as recited in claim 4 further including the step of recovering the processors that are in “

Recovery Pending”

state without adversely affecting the users.

6. A method for use in a communications system as recited in claim 1 further including, after the step of stopping, retrying recovery during the predetermined window of time on the next day.

7. A network access server (NAS) for use in a communications system having a first communications device coupled to communicate through a public switching telephone network (PSTN), and a second communications device, coupled to communicate through a packet switching network, the NAS including processors for transferring communications information between first and the second communications devices wherein the processors require upgrading or recovery comprising:

a modem card coupled to receive telephone calls and operative to generate processed telephone calls including,

one or more modules, each module having a module controller, a memory block and a plurality of digital signal processors for executing code, stored in the memory block, to perform various tasks, the module controller coupled to the plurality of digital signal processors for attempting recovery, during upgrading or recovery, of one or more of the digital signal processors of a particular module having been designated as ‘

bad’

, the attempted recovery occurring during a predetermined window of time and if the attempted recovery takes longer than the window of time, the module controller for stopping the attempted recovery,

wherein the impact of recovery or upgrade of the digital signal processors to the users is minimized while the overall system capacity is maximized.

8. A network access server as recited in claim 7 wherein the window of time is defined by a predetermined duration of time in the day during which the communications system is least utilized by the users.

9. A network access server as recited in claim 7 wherein if the attempted recovery takes longer than the predetermined window of time, said module controller is further for retrying recovery during the predetermined window of time on the next.

10. A network access server as recited in claim 7 further including a processor card coupled to said modem card for assigning an in-coming call to one of the digital signal processors of the particular module.

11. A network access server as recited in claim 7 wherein the processors included within the NAS for designating the particular module as being ‘

bad’

.

12. A network access server as recited in claim 7 wherein the packet switching network is the Internet and the network access server further includes an ethernet connection for coupling the modem card and the processor card to the Internet.

13. A network access server as recited in claim 7 further including a controller card responsive to T1 transmission lines coupling information from the public switch telephone network and operative to provide the modem card and the processor individual calls for processing.

14. A network access server as recited in claim 7 wherein the information being coupled onto the T1 lines is Time Division Multiplexed.

15. A network access server as recited in claim 7 further including a controller card responsive to E1 transmission lines coupling information from the public switch telephone network and operative to provide the modem card and the processor individual calls for processing.

16. A network access server as recited in claim 7 wherein the information being coupled onto the E1 lines is Time Division Multiplexed.

17. A network access server as recited in claim 7 wherein the processor is further for disabling one or more of the plurality of digital signal processors that have been designated as ‘

bad’

.

18. A network access server as recited in claim 7 further including a failed counter for counting the number of consecutive digital signal processor failures prior to determining the same is ‘

bad’

.

19. A network access server as recited in claim 10 further including a shared bus for coupling the processor and the modem card.

20. A network access server as recited in claim 7 wherein the memory block of the particular module includes code for use by the digital signal processors of the particular module.

21. A network access server as recited in claim 10 wherein the particular module includes separate storage spaces for storing code corresponding to a digital signal processor of the particular module.

22. A network access server as recited in claim 10 wherein said processor includes nonvolatile memory storage space for storing code for use by the digital signal processors and for downloading the code to a ‘

bad’

digital signal processor during upgrading or recovery.

23. A network access server as recited in claim 10 wherein said processor includes a hard disk device for storing code for use by the digital signal processors and for downloading the code to a ‘

bad’

digital signal processor during upgrading or recovery.

24. A network access server as recited in claim 10 wherein code for use by the digital signal processors is stored externally to the NAS.