Claims
- 1. A method to provide enhanced peer redundancy to an Asynchronous Transfer Mode (ATM) emulated local area network (ELAN) wherein the ELAN is served by a primary LAN emulation server (LES), a broadcast and unknown server (BUS) and a LAN emulation configuration server (LECS), the method comprising the steps of:coupling a peer LES/BUS to the ELAN; establishing an enhanced peer redundancy virtual channel connection (VCC) between the primary LES/BUS and the peer LES/BUS; transmitting a plurality of status messages between the primary LES/BUS and the peer LES/BUS; comparing a first number of LAN emulation clients (LECs) joined with the primary LES/BUS and a second number of LECs joined with the peer LES/BUS; and providing ELAN services to all of the LECs in the ELAN by the LES/BUS having a greater number of joined LECs.
- 2. The method to provide enhanced peer redundancy of claim 1 wherein the step of transmitting a plurality of status messages includes both the primary LES/BUS and the peer LES/BUS transmitting status messages to each other asynchronously at least every two seconds, each status message containing the number of LECs joined to the corresponding LES/BUS.
- 3. The method to provide enhanced peer redundancy of claim 1 wherein the step of establishing an enhanced peer redundancy VCC is performed by the primary LES/BUS.
- 4. The method to provide enhanced peer redundancy of claim 1 wherein if the enhanced peer redundancy VCC is rejected by the peer LES/BUS, the primary LES/BUS initiates a redundancy VCC with the peer LES/BUS that, if successful, enables the primary LES/BUS to become an active LES/BUS and places the peer LES/BUS in a dormant mode.
- 5. The method to provide enhanced peer redundancy of claim 4 wherein the active LES/BUS provides ELAN services to each requesting LEC in the ELAN.
- 6. The method to provide enhanced peer redundancy of claim 5 wherein if an enhanced peer redundancy VCC cannot be establised or the peer LES/BUS has more joined LECs than the primary LES/BUS, enabling the peer LES/BUS to become the active LES/BUS.
- 7. The method to provide enhanced peer redundancy of claim 4 wherein the peer LES/BUS becomes the active LES/BUS if the redundancy VCC between the primary LES/BUS and the peer LES/BUS is disconnected until such time that an enhanced peer redundancy VCC or a redundancy VCC is re-established.
- 8. The method to provide enhanced peer redundancy of claim 1 wherein if one of either the primary LES/BUS or the peer LES/BUS is unable to transmit two consecutive status messages to the other LES/BUS, the other LES/BUS takes over providing ELAN services to any new LEC that joins the ELAN at least until the one LES/BUS is again able to transmit status messages.
- 9. The method to provide enhanced peer redundancy of claim 1 further including the step of querying the LECS to determine if it is co-located with either the primary LES/BUS or the peer LES/BUS.
- 10. The method to provide enhanced peer redundancy of claim 9 wherein if the LECS is co-located with the LES/BUS providing ELAN services, returning an ATM address of the co-located LES/BUS.
- 11. The method to provide enhanced peer redundancy of claim 9 wherein if the LECS is co-located with the LES/BUS not providing ELAN services, returning an ATM address of the other LES/BUS.
- 12. The method to provide enhanced peer redundancy of claim 1 further including the step of an operator invoking a command at an operator console associated with the primary LES/BUS to take over control of all LECs in the ELAN from an active peer LES/BUS.
- 13. The method to provide enhanced peer redundancy of claim 12 further including the step of the active peer LES/BUS terminating all of its LECs and yielding to the primary LES/BUS upon receipt of the takeover command.
- 14. A computer program product adaptable for storage on a program storage media at a network device, the computer program product operable for providing enhanced peer redundancy to an Asynchronous Transfer Mode (ATM) emulated local area network (ELAN) wherein the ELAN is served by a primary LAN emulation server (LES), a broadcast and unknown server (BUS) and a LAN emulation configuration server (LECS), the computer program product comprising:program code for coupling a peer LES/BUS to the ELAN; program code for establishing an enhanced peer redundancy virtual channel connection (VCC) between the primary LES/BUS and the peer LES/BUS; program code for transmitting a plurality of status messages between the primary LES/BUS and the peer LES/BUS; program code for comparing a first number of LAN emulation clients (LECs) joined with the primary LES/BUS and a second number of LECs joined with the peer LES/BUS; and program code for providing ELAN services to all of the in the ELAN by the LES/BUS having a greater number of joined LECs.
- 15. The computer program product of claim 14 wherein the program code for transmitting a plurality of status messages includes program code for both the primary LES/BUS and the peer LES/BUS to transmit status messages to each other asynchronously at least every two seconds, each status message containing the number of LECs joined to the corresponding LES/BUS.
- 16. The computer program product of claim 14 wherein the program code for establishing an enhanced peer redundancy VCC is executed by the primary LES/BUS.
- 17. The computer program product of claim 14 including program code for the primary LES/BUS to initiate a redundancy VCC with the peer LES/BUS, if the enhanced peer redundancy VCC is rejected by the peer LES/BUS, and that enables the primary LES/BUS to become an active LES/BUS and places the peer LES/BUS in a dormant mode.
- 18. The computer program product of claim 14 including program code to enable the active LES/BUS provide ELAN services to each requesting LEC in the ELAN.
- 19. The computer program product of claim 18 including program code for enabling the peer LES/BUS to become the active LES/BUS, if an enhanced peer redundancy VCC cannot be established or the peer LES/BUS has more joined LECs than the primary LES/BUS.
- 20. The computer program product of claim 17 including program code for the peer LES/BUS to become the active LES/BUS if the redundancy VCC between the primary LES/BUS and the peer LES/BUS is disconnected until such time that an enhanced peer redundancy VCC or a redundancy VCC is re-established.
- 21. The computer program product of claim 14 including program code for one of either the primary LES/BUS or the peer LES/BUS to take over providing ELAN services to any new LEC that joins the ELAN at least until the other LES/BUS is again able to transmit status messages, if the other LES/BUS is unable to transmit two consecutive status messages to the one LES/BUS.
- 22. The computer program product of claim 14 further including the program code for querying the LECS to determine if it is co-located with either the primary LES/BUS or the peer LES/BUS.
- 23. The computer program product of claim 22 including program code for returning an ATM address of co-located LES/BUS, if the LECS is co-located with the LES/BUS providing ELAN services.
- 24. The computer program product of claim 22 including program code for returning an ATM address of the other LES/BUS, if the LECS is co-located with the LES/BUS not providing ELAN services.
- 25. The computer program product of claim 14, further including program code to invoke a command at an operator console associated with the primary LES/BUS to take over control of all LECs in the ELAN from an active peer LES/BUS.
- 26. The computer program product of claim 25 further including program code for enabling the active peer LES/BUS to terminate all of its LECs and yield to the primary LES/BUS upon receipt of the takeover command.
- 27. A system to provide enhanced peer redundancy to an Asynchronous Transfer Mode (ATM) emulated local area network (ELAN) wherein the ELAN is served by a primary LAN emulation server (LES), a broadcast and unknown server (BUS) and a LAN emulation configuration server (LECS), the system comprising:means for coupling a peer LES/BUS to the ELAN; means for establishing an enhanced peer redundancy virtual channel connection (VCC) between the primary LES/BUS and the peer LES/BUS; means for transmitting a plurality of status massages between the primary LES/BUS and the peer LES/BUS; means for comparing a first number of LAN emulation clients (LECs) joined with the primary LES/BUS and a second number of LECs joined with the peer LES/BUS; and means for providing ELAN services to all of the LECs in the ELAN by the LES/BUS having a greater number of joined LECs.
- 28. The system to provide enhanced peer redundancy of claim 27 wherein the means for transmitting a plurality of status messages includes means at the primary LES/BUS and the peer LES/BUS for transmitting status messages to each other asynchronously at least every two seconds, each status message containing the number of LECs joined to the corresponding LES/BUS.
- 29. The system to provide enhanced peer redundancy of claim 27 wherein the means for establishing an enhanced peer redundancy VCC is located at the primary LES/BUS.
- 30. The system to provide enhanced peer redundancy of claim 27 including means for the primary LES/BUS to initiate a redundancy VCC with the peer LES/BUS that enables the primary LES/BUS to become an active LES/BUS and places the peer LES/BUS in a dormant mode if the enhanced peer redundancy VCC is rejected by the peer LES/BUS.
- 31. The system to provide enhanced peer redundancy of claim 30 including means for the active LES/BUS to provide ELAN services to each requesting LEC in the ELAN.
- 32. The system to provide enhanced peer redundancy of claim 31 including means for enabling the peer LES/BUS to become the active LES/BUS if an enhanced peer redundancy VCC cannot be established or the peer LES/BUS has more joined LECs than the primary LES/BUS.
- 33. The system to provide enhanced peer redundancy of claim 30 including means for the peer LES/BUS to become the active LES/BUS if the redundancy VCC between the primary LES/BUS and the peer LES/BUS is disconnected until such time that an enhanced peer redundancy VCC or a redundancy VCC is re-established.
- 34. The system to provide enhanced peer redundancy of claim 27 including means for one of either the primary LES/BUS or the peer LES/BUS to take over providing ELAN services to any new LEC that joins the ELAN at least until the other LES/BUS is again able to transmit status messages if the other LES/BUS is unable to transmit two consecutive status messages to the one LES/BUS.
- 35. The system to provide enhanced peer redundancy of claim 27 further including means for querying the LECS to determine if it is co-located with either the primary LES/BUS or the peer LES/BUS.
- 36. The system to provide enhanced peer redundancy of claim 35 including means for returning an ATM address of the co-located LES/BUS if the LECS is co-located with the LES/BUS providing ELAN services.
- 37. The system to provide enhanced peer redundancy of claim 35 including means for returning an ATM address of the other LES/BUS if the LECS is co-located with the LES/BUS not providing ELAN services.
- 38. The system to provide enhanced peer redundancy of claim 27 further including a user interface to invoke a command operator console associated with the primary LES/BUS to take over control of all LECs in the ELAN from an active peer LES/BUS.
- 39. The system to provide enhanced peer redundancy of claim 38 further including means for the active peer LES/BUS to terminate all of its LECs and yield to the primary LES/BUS upon receipt of the takeover command.
CROSS REFERENCE TO RELATED APPLICATION
This application is related to co-pending and commonly assigned patent application METHOD AND SYSTEM FOR PROVIDING REDUNDANCY TO ASYNCHRONOUS TRANSFER MODE EMULATED LOCAL-AREA NETWORKS, Ser. No. 09/017,306, now U.S. Pat. No. 6,226,297, filed Jan. 30, 1997.
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Non-Patent Literature Citations (4)
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