Method and apparatus for wireless network architecture based on subscriber distribution

• US 6,097,951 A
• Filed: 08/06/1998
• Issued: 08/01/2000
• Est. Priority Date: 08/06/1997
• Status: Expired due to Fees

• Current Assignee: Rockstar Consortium US LP (Rockstar Consortium Inc.)
• Original Assignee: Northern Telecom Limited (Nortel Networks Corporation)
• Inventors: Reece, Christopher S., Xu, Jim, Ernam, Hakan
• Primary Examiner(s): Vo, Nguyen
• Assistant Examiner(s): BANKS HAROLD, MARSHA DENISE
• Application Number:
  US09/130,293
• Time in Patent Office: 726 Days
• Field of Search: 455/445, 455/446, 455/560, 455/433, 455/426, 455/432, 455/436, 455/439, 455/435, 455/422, 455/507, 455/508
• US Class Current: 455/433
• CPC Class Codes: H04W 16/18 Network planning tools
• CPC Class Codes: H04W 8/06 Registration at serving network Location Register, VLR or user mobility server
• CPC Class Codes: H04W 88/16 Gateway arrangements

Abstract

A method and apparatus for scaling a wireless telecommunications network having an architecture based upon subscriber distribution includes providing a base station subsystem (BSS) and a pool of mobile switching centers (MSCs) interconnected with one another. The mobile switching centers include visitor location registers (VLRs). Lastly, a dispatcher mobile switching center (DMSC) is provided, the dispatcher mobile switching center being coupled between the base station subsystem (BSS) and the pool of mobile switching centers (MSCs) for establishing communication between the base station subsystem (BSS) and the pool of mobile switching centers (MSCs). The dispatcher mobile switching center (DMSC) further provides for distributing mobile station subscribers and call related work among the pool of mobile switching centers (MSCs).

Claims

1. A method for scaling a wireless telecommunications network having an architecture based upon subscriber distribution, said method comprising the steps of:

providing a base station subsystem (BSS);

providing a pool of mobile switching centers (MSCs) interconnected with one another, the mobile switching centers including visitor location registers (VLRs); and

providing a dispatcher mobile switching center (DMSC) coupled between the base station subsystem (BSS) and the pool of mobile switching centers (MSCs) for establishing communication between the base station subsystem (BSS) and the pool of mobile switching centers (MSCs), the dispatcher mobile switching center (DMSC) further for distributing mobile station subscribers and call related work among the pool of mobile switching centers (MSCs).

2. The method of claim 1, wherein said step of providing the dispatcher mobile switching center (DMSC) further includes providing a table of subscribers and corresponding MSC/VLR entries, each subscriber corresponding to a mobile station identification (mob_-- id) and each corresponding MSC/VLR entry corresponding to a particular mobile switching center/visitor location register identification (VLR_-- id) of the pool of mobile switching centers (MSCs), a corresponding MSC/VLR entry being assigned to the subscriber when the mobile station of the respective subscriber is initially powered up.

3. The method of claim 2, wherein said step of providing the dispatcher mobile switching center (DMSC) further includes assigning a subscriber mobile station identification (mob_-- id) to a corresponding mobile switching center/visitor location identification (VLR_-- id) according to a prescribed assignment.

4. The method of claim 2, wherein said step of providing the dispatcher mobile switching center (DMSC) further includes making use of the table entry associations of subscribers and corresponding MSC/VLR entries in order to decide which mobile switching center (MSC) of the pool of mobile switching centers (MSCs) to route a mobile originated call when one occurs.

5. The method of claim 2, wherein said step of providing the dispatcher mobile switching center (DMSC) further includes performing a land to land call upon the occurrence of a mobile terminated call/paging procedure, a home location register (HLR) being provided for tracking of visitor location registers (VLRs) and subscribers according to GSM standards, the mobile terminated call being first routed to a gateway mobile switching center (GMSC) and then being routed to the base station subsystem (BSS) through the dispatcher mobile switching center (DMSC).

6. The method of claim 2, wherein the table includes MSC/VLR identifications (VLR_-- ids) indexed by identity of mobile subscribers (mob_-- ids).

7. The method of claim 6, wherein the table further includes a pseudo visitor location register (pseudo VLR) having a structure optimized for very fast searches and updates.

8. The method of claim 2, wherein upon an initial attach of a mobile station, the dispatcher mobile switching center (DMSC) checks the table entry associations to determine if the mobile station is registered in one of the MSC/VLRs of the pool of MSCs and (a) if the mobile station is registered, then an attach message is routed to the corresponding MSC/VLR and an attach operation is completed, and (b) if the mobile station is not registered, then the dispatcher mobile switching center (DMSC) assigns the mobile station to one of the MSC/VLRs of the pool of MSCs depending upon a prescribed criteria and keeps a record of the association in the table of the dispatcher mobile switching center (DMSC).

9. The method of claim 2, wherein upon a mobile station originated call, the BSS initiates a call setup with the dispatcher mobile switching center (DMSC), the dispatcher mobile switching center (DMSC) then checks the table entry associations to determine if the mobile station is registered in one of the MSC/VLRs of the pool of MSCs and (a) if the mobile station is registered, then the DMSC acts as a transparent relay between the BSS and the corresponding MSC of the pool of MSCs, the DMSC transferring all A-interface messages transparently to the corresponding MSC, wherein the call setup proceeds thereafter according to GSM standards, and (b) if the mobile station is not registered, then the dispatcher mobile switching center (DMSC) assigns the mobile station to one of the MSC/VLRs of the pool of MSCs depending upon a prescribed criteria, keeps a record of the association in the table of the dispatcher mobile switching center (DMSC), and then proceeds as if the mobile station is registered.

10. The method of claim 1, wherein said step of providing the pool of mobile switching centers (MSCs) includes providing at least five (5) mobile switching centers.

11. The method of claim 1, wherein said step of providing the dispatcher mobile switching center (DMSC) includes only traffic routing and subscriber assignments, the dispatcher mobile switching center (DMSC) for distributing call processing loads onto the mobile switching centers (MSCs) of the pool of mobile switching centers (MSCs).

12. The method of claim 1, wherein said step of providing the dispatcher mobile switching center (DMSC) includes traffic routing and subscriber assignments, the dispatcher mobile switching center (DMSC) for distributing call processing loads onto the mobile switching centers (MSCs) of the pool of mobile switching centers (MSCs), the dispatcher mobile switching center (DMSC) further having a capability of having resident subscribers and for performing call processing of its own.

13. A wireless telecommunications network having an architecture based upon subscriber distribution, said network comprising:

a base station subsystem (BSS);

a pool of mobile switching centers (MSCs) interconnected with one another, the mobile switching centers including visitor location registers (VLRs); and

a dispatcher mobile switching center (DMSC) coupled between said base station subsystem (BSS) and said pool of mobile switching centers (MSCs) for establishing communication between said base station subsystem (BSS) and said pool of mobile switching centers (MSCs), said dispatcher mobile switching center (DMSC) further for distributing mobile station subscribers and call related work among said pool of mobile switching centers (MSCs).

14. The wireless telecommunications network of claim 13, wherein said dispatcher mobile switching center (DMSC) includes a table of subscribers and corresponding MSC/VLR entries, each subscriber corresponding to a mobile station identification (mob_-- id) and each corresponding MSC/VLR entry corresponding to a particular mobile switching center/visitor location register identification (VLR_-- id) of said pool of mobile switching centers (MSCs), a corresponding MSC/VLR entry being assigned to the subscriber when the mobile station of the respective subscriber is initially powered up.

15. The wireless telecommunications network of claim 14, wherein said dispatcher mobile switching center (DMSC) assigns a subscriber mobile station identification (mob_-- id) to a corresponding mobile switching center/visitor location identification (VLR_-- id) according to a prescribed assignment.

16. The wireless telecommunications network of claim 14, wherein said dispatcher mobile switching center (DMSC) makes use of the table entry associations of subscribers and corresponding MSC/VLR entries in order to decide which mobile switching center (MSC) of said pool of mobile switching centers (MSCs) to route a mobile originated call when one occurs.

17. The wireless telecommunications network of claim 14, wherein said dispatcher mobile switching center (DMSC) performs a land to land call upon the occurrence of a mobile terminated call/paging procedure, a home location register (HLR) being provided for tracking of visitor location registers (VLRs) and subscribers according to GSM standards, the mobile terminated call being first routed to a gateway mobile switching center (GMSC) and then being routed to said base station subsystem (BSS) through said dispatcher mobile switching center (DMSC).

18. The wireless telecommunications network of claim 14, wherein the table is further characterized in that the MSC/VLR identifications (VLR_-- ids) are indexed by identity of mobile subscribers (mob_-- ids).

19. The wireless telecommunications network of claim 18, further wherein the table includes a pseudo visitor location register (pseudo VLR) having a structure optimized for very fast searches and updates.

20. The wireless telecommunications network of claim 14, wherein upon an initial attach of a mobile station, said dispatcher mobile switching center (DMSC) checks the table entry associations to determine if the mobile station is registered in one of the MSC/VLRs of said pool of MSCs and (a) if the mobile station is registered, then an attach message is routed to the corresponding MSC/VLR and an attach operation is completed, and (b) if the mobile station is not registered, then said dispatcher mobile switching center (DMSC) assigns the mobile station to one of the MSC/VLRs of said pool of MSCs depending upon a prescribed criteria and keeps a record of the association in the table of said dispatcher mobile switching center.

21. The wireless telecommunications network of claim 14, wherein upon a mobile station originated call, said BSS initiates a call setup with said dispatcher mobile switching center (DMSC), said dispatcher mobile switching center (DMSC) then checks the table entry associations to determine if the mobile station is registered in one of the MSC/VLRs of said pool of MSCs and (a) if the mobile station is registered, then said DMSC acts as a transparent relay between said BSS and the corresponding MSC of said pool of MSCs, said DMSC transferring all A-interface messages transparently to the corresponding MSC, wherein the call setup proceeds thereafter according to GSM standards, and (b) if the mobile station is not registered, then said dispatcher mobile switching center (DMSC) assigns the mobile station to one of the MSC/VLRs of said pool of MSCs depending upon a prescribed criteria, keeps a record of the association in the table of said dispatcher mobile switching center (DMSC), and then proceeds as if the mobile station is registered.

22. The wireless telecommunications network of claim 13, wherein said pool of mobile switching centers (MSCs) includes at least five (5) mobile switching centers.

23. The wireless telecommunications network of claim 13, wherein said dispatcher mobile switching center (DMSC) provides only traffic routing and subscriber assignments, said dispatcher mobile switching center (DMSC) for distributing call processing loads onto the mobile switching centers (MSCs) of said pool of mobile switching centers (MSCs).

24. The wireless telecommunications network of claim 13, wherein said dispatcher mobile switching center (DMSC) provides traffic routing and subscriber assignments, said dispatcher mobile switching center (DMSC) for distributing call processing loads onto the mobile switching centers (MSCs) of said pool of mobile switching centers (MSCs), said dispatcher mobile switching center (DMSC) further including a capability of having resident subscribers and for performing call processing of its own.

25. A wireless telecommunications network having an architecture based upon subscriber distribution, said network comprising:

a base station subsystem (BSS);

a pool of mobile switching centers (MSCs) interconnected with one another, the mobile switching centers including visitor location registers (VLRs); and

a dispatcher mobile switching center (DMSC) coupled between said base station subsystem (BSS) and said pool of mobile switching centers (MSCs) for establishing communication between said base station subsystem (BSS) and said pool of mobile switching centers (MSCs), said dispatcher mobile switching center (DMSC) further for distributing mobile station subscribers and call related work among said pool of mobile switching centers (MSCs),

wherein said dispatcher mobile switching center (DMSC) includes a table of subscribers and corresponding MSC/VLR entries, each subscriber corresponding to a mobile station identification (mob_-- id) and each corresponding MSC/VLR entry corresponding to a particular mobile switching center/visitor location register identification (VLR_-- id) of said pool of mobile switching centers (MSCs),

wherein the table is further characterized in that the MSC/VLR identifications (VLR_-- ids) are indexed by identity of mobile subscribers (mob_-- ids).