Dual AAL1 device and synchronization method used therewith

• US 6,882,650 B2
• Filed: 05/17/2001
• Issued: 04/19/2005
• Est. Priority Date: 05/17/2000
• Status: Active Grant

• Current Assignee: Juniper Networks Incorporated
• Original Assignee: Juniper Networks Incorporated
• Inventors: Shiraishi, Ken, Shimanuki, Tomoharu
• Primary Examiner(s): Nguyen, Chau
• Assistant Examiner(s): Ng, Christine
• Application Number:
  US09/858,637
• Publication Number:
  US 20010043596A1
• Time in Patent Office: 1,433 Days
• Field of Search: 370216-228, 370/395.1, 370/395.6, 370/465, 370/466, 370/469, 370/473, 370/474
• US Class Current: 370/395.6
• CPC Class Codes: H04L 12/2854 Wide area networks, e.g. public data networks
• CPC Class Codes: H04L 12/5601 Transfer mode dependent, e.g. ATM
• CPC Class Codes: H04L 2012/5618 Bridges, gateways [GW] or interworking units [IWU]
• CPC Class Codes: H04L 2012/5654 using the AAL1
• CPC Class Codes: H04L 2012/5665 Interaction of ATM with other protocols
• CPC Class Codes: H04L 2012/5674 Synchronisation, timing recovery or alignment
• CPC Class Codes: H04Q 11/0478 Provisions for broadband connections

Abstract

Upon receipt of a synchronization request from the CPU, the AAL1 device of the act system causes its cell forming section to extract the allocation position information for the SAR-PDU payload about a particular time slot in the current frame and, via the synchronization information send/receive section, transfers the information to the AAL1 device of the standby system. The AAL1 device of the standby system causes its operation processing section to calculate the allocation position of a particular time slot in the next frame for the SAR-PDU payload based on the above allocation position information. The AAL1 device of the standby system starts allocation of the data of and following a particular time slot of the next frame to the SAR-PDU payload starting from the position indicated by the calculation result.

Claims

1. A dual AAL1 (ATM Adaptation Layer Type 1) device with a dual configuration consisting of an act system and a standby system to convert the STM (Synchronous Transfer Mode) data into ATM (Asynchronous Transfer Mode) cells in said act system and said standby system respectively comprising, for said act system and said standby system respectively,

means for extracting the SC (Sequence Count) information of said ATM cell where a particular time slot of said STM data is allocated and the allocation position information for the SAR-PDU (Segmentation And Re-assembly-Protocol Data Unit) payload when this means belong to said act system, and

means for calculating the SC of said ATM cell where a particular time slot of said STM data in the next frame is allocated and the allocation position for said SAR-PDU payload based on the SC information and the allocation position information extracted by said act system when this means belongs to said standby system.

2. A dual AAL1 device as set forth in claim 1, wherein

said act system extracts the SC information of said ATM cell to which a particular time slot of said STM data in the applicable frame is allocated and the allocation position information for said SAR-PDU payload upon receipt of a synchronization request and notifies such information to said standby system, and

said standby system uses said SC information and said allocation position information from said act system to calculate the SC of said ATM cell to which a particular time slot of said STM data in the next frame is allocated and the allocation position for said SAR-PDU payload and then allocates the particular time slot of said STM data in the next frame to that position.

3. A dual AAL1 device with a dual configuration consisting of an act system and a standby system to convert the STM data into ATM cells in said act system and said standby system respectively comprising, for said act system and said standby system respectively,

means for extracting the SC information of said ATM cell to which the pointer is inserted and the pointer value information when this means belongs to said act system, and

means for calculating the SC of said ATM cell to which a particular time slot of said STM data in the next frame is allocated and the allocation position for the SAR-PDU payload based on said SC information and said pointer value information extracted by said act system when this means belongs to said standby system.

4. A dual AAL1 device as set forth in claim 3, wherein

said act system extracts the SC information of said ATM cell to which said pointer is inserted and said pointer value information upon receipt of a synchronization request and notifies the information to said standby system, and

said standby system calculates the SC of said ATM cell to which a particular time slot of said STM data in the next frame is allocated and the allocation position for said SAR-PDU payload based on the SC information of said ATM cell to which the pointer is inserted and said pointer value information from said act system and allocates the particular time slot of said STM data in the next frame at that position.

5. A dual AAL1 device with a dual configuration consisting of an act system and a standby system to convert the STM data into ATM cells in said act system and said standby system respectively comprising, for said act system and said standby system respectively,

means for extracting the SC information of said ATM cell to which a particular time slot of said STM data is allocated and the allocation position information for the SAR-PDU payload, and

means for calculating the SC of said ATM cell to which a particular time slot of said STM data in the next frame is allocated and the allocation position for said SAR-PDU payload based on the extracted SC information and the allocation position information,

the SC of said ATM cell and the allocation position for said SAR-PDU payload are calculated and notified to said standby system when this means belongs to the act system.

6. A dual AAL1 device as set forth in claim 5, wherein

said act system extracts the SC information of said ATM cell to which a particular time slot of said STM data in the applicable frame is allocated and the allocation position information for said SAR-PDU payload upon receipt of a synchronization request, calculates the SC of said ATM cell to which a particular time slot of said STM data in the next frame is allocated and the allocation position for said SAR-PDU payload and notifies the calculation results to said standby system, and

said standby system allocates the particular time slot of said STM data in the next frame to the allocation position obtained from said act system.

7. A dual AAL1 device with a dual configuration consisting of an act system and a standby system to convert the STM data into ATM cells in said act system and said standby system respectively comprising, for said act system and said standby system respectively,

means for extracting the SC information of said ATM cell to which the pointer is inserted and the pointer value information, and

means for calculating the SC of said ATM cell to which a particular time slot of said STM data in the next frame is allocated and the allocation position for the SAR-PDU payload based on said extracted SC information and pointer value information and,

in case of said act system, the SC of said ATM cell and the allocation position of said SAR-PDU payload being calculated and notified to said standby system.

8. A dual AAL1 device as set forth in claim 7, wherein

said act system extracts the SC information of said ATM cell to which said pointer is inserted and said pointer value information upon receipt of a synchronization request, calculates the SC of said ATM cell to which a particular time slot of said STM data in the next frame is allocated and the allocation position for said SAR-PDU payload and notifies the calculation results to said standby system and

said standby system allocates the particular time slot of said STM data in the next frame to the allocation position obtained from said act system.

9. A synchronization method for a dual AAL1 device with a dual configuration consisting of an act system and a standby system to convert the STM data into ATM cells in said act system and said standby system respectively comprising:

a step for said act system to extract the SC of said ATM cell to which a particular time slot of said STM data in the applicable frame is allocated and the allocation position information for the SAR-PDU payload upon receipt of a synchronization request and to notify the information to said standby system, and

a step for said standby system to calculate the SC of said ATM cell in which a particular time slot of said STM data in the next frame is allocated and the allocation position for said SAR-PDU payload based on said SC information and said allocation position information from said act system and to allocate the particular time slot of said STM data in the next frame at that position.

10. A synchronization method for a dual AAL1 device with a dual configuration consisting of an act system and a standby system to convert the STM data into ATM cells in said act system and said standby system respectively comprising:

a step for said act system

extracting the SC information of said ATM cell to which the pointer is inserted and the pointer value information upon receipt of a synchronization request and notifying the information to said standby system, and

a step for said standby system

calculating the SC of said ATM cell to which a particular time slot of said STM data in the next frame is allocated and the allocation position for the SAR-PDU payload based on the SC information of said ATM cell to which said pointer is inserted and said pointer value information from said act system and allocating the particular time slot of said STM data in the next frame to that position.

11. A synchronization method for a dual AAL1 device with a dual configuration consisting of an act system and a standby system to convert the STM data into ATM cells in said act system and said standby system respectively comprising:

a step for said act system

extracting the SC information of said ATM cell to which a particular time slot of said STM data in the applicable frame is allocated and the allocation position information for the SAR-PDU payload upon receipt of a synchronization request, calculating the SC of said ATM cell to which a particular time slot of said STM data in the next frame is allocated and the allocation position for said SAR-PDU payload and to notifying the calculation result to said standby system, and

a step for said standby system

allocating the particular time slot of said STM data in the next frame to the allocation position from said act system.

12. A synchronization method for a dual AAL1 device with a dual configuration consisting of an act system and a standby system to convert the STM data into ATM cells in said act system and said standby system respectively comprising:

a step for said act system

extracting the SC information of said ATM cell to which the pointer is inserted and the pointer value information upon receipt of a synchronization request, to calculate the SC of said ATM cell to which a particular time slot of said STM data in the next frame is allocated and the allocation position for the SAR-PDU payload and notifying the calculation result to said standby system, and

a step for said standby system

allocating the particular time slot of said STM data in the next frame to the allocation position from said act system.

13. A dual AAL1 device with a dual configuration consisting of an act system and a standby system to convert the STM data into ATM cells in said act system and said standby system respectively comprising, for said act system and said standby system respectively,

a cell forming section which, when it belongs to said act system, extracts the SC information of said ATM cell where a particular time slot of said STM data is allocated and the allocation position information for the SAR-PDU payload, and

an operation processing section which, when it belongs to said standby system, uses the SC information and the allocation position information extracted by said act system to calculate the SC of said ATM cell where a particular time slot of said STM data in the next frame is allocated and the allocation position for said SAR-PDU payload.

14. A dual AAL1 device as set forth in claim 13, wherein

said act system extracts the SC information of said ATM cell to which a particular time slot of said STM data in the applicable frame is allocated and the allocation position information for said SAR-PDU payload upon receipt of a synchronization request and notifies the information to said standby system, and

said standby system uses said SC information and said allocation position information from said act system to calculate the SC of said ATM cell to which a particular time slot of said STM data in the next frame is allocated and the allocation position for said SAR-PDU payload and allocates the particular time slot of said STM data in the next frame to that position.

15. A dual AAL1 device with a dual configuration consisting of an act system and a standby system to convert the STM data into ATM cells in said act system and said standby system respectively comprising, for said act system and said standby system respectively,

a cell forming section which, when it belongs to said act system, extracts the SC information of said ATM cell where the pointer is inserted and the pointer value information, and

an operation processing section which, when it belongs to said standby system, uses the SC information and said pointer value information extracted by said act system to calculate the SC of said ATM cell where particular time slot of said STM data in the next frame is allocated and the allocation position for the SAR-PDU payload.

16. A dual AAL1 device as set forth in claim 15, wherein

said act system extracts the SC information of said ATM cell to which said pointer is inserted and said pointer value information upon receipt of a synchronization request and notifies the information to said standby system, and

said standby system uses the SC information of said ATM cell to which said pointer is inserted and said pointer value information obtained from said act system to calculate the SC of said ATM cell to which a particular time slot of said STM data in the next frame is allocated and the allocation position for said SAR-PDU payload and allocates the particular time slot of said STM data in the next frame to that position.

17. A dual AAL1 device with a dual configuration consisting of an act system and a standby system to convert the STM data into ATM cells in said act system and said standby system respectively comprising,

for said act system and said standby system respectively,

a cell forming section which extracts the SC information of said ATM cell where a particular time slot of said STM data is allocated and the allocation position information for the SAR-PDU payload and

an operation processing section which uses the extracted SC information and the allocation position information to calculate the SC of said ATM cell where a particular time slot of said STM data in the next frame is allocated and the allocation position for said SAR-PDU payload and,

in case of said act system, the SC of said ATM cell and the allocation position for said SAR-PDU payload being calculated and notified to said standby system.

18. A dual AAL1 device as set forth in claim 17, wherein

said act system extracts the SC information of said ATM cell to which a particular time slot of said STM data in the applicable frame is allocated and the allocation position information for said SAR-PDU payload upon receipt of a synchronization request and calculates the SC of said ATM cell to which a particular time slot of said STM data in the next frame is allocated and the allocation position for said SAR-PDU payload and notifies the calculation results to said standby system, and

said standby system allocates the particular time slot of said STM data in the next frame to the allocation position obtained from said act system.

19. A dual AAL1 device with a dual configuration consisting of an act system and a standby system to convert the STM data into ATM cells in said act system and said standby system respectively comprising, in said act system and said standby system respectively,

a cell forming section which extracts the SC information of said ATM cell where the pointer is inserted and the pointer value information

an operation processing section which uses the extracted SC information and said pointer value information to calculate the SC of said ATM cell where a particular time slot of said STM data in the next frame is allocated and the allocation position for said SAR-PDU payload and,

in case of said act system, the SC of said ATM cell and the allocation position for the SAR-PDU payload being calculated and notified to said standby system.

20. A dual AAL1 device as set forth in claim 19, wherein

said act system extracts the SC information of said ATM cell to which said pointer is inserted and said pointer value information upon receipt of a synchronization request and calculates the SC of said ATM cell to which a particular time slot of said STM data in the next frame is allocated and the allocation position for said SAR-PDU payload and notifies the calculation results to said standby system and

said standby system allocates the particular time slot of said STM data in the next frame to the allocation position obtained from said act system.