Subscribers database proofing using a checksum in a telecommunications system

• US 7,058,402 B2
• Filed: 05/23/2001
• Issued: 06/06/2006
• Est. Priority Date: 05/23/2001
• Status: Expired due to Term

• Current Assignee: Unwired Planet LLC (JP Morgan Chase & Co)
• Original Assignee: Telefonaktiebolaget LM Ericsson
• Inventors: Hansson, Rolf Elis Gustaf, Karlsson, Bernt
• Primary Examiner(s): Appah, Charles N
• Assistant Examiner(s): ZEWDU, MELESS NMN
• Application Number:
  US09/864,468
• Publication Number:
  US 20020177439A1
• Time in Patent Office: 1,840 Days
• Field of Search: 455/433, 455/435.1, 455/436, 455437-440, 455/442, 455/552.1, 4554561-4566, 455/445, 455/435.2, 455/435.3, 455/550.1, 455560-561, 455/404.2, 455410-411, 455/457, 380247-248, 380/255, 380/258, 380/270, 709227-228, 709/310, 709245-246, 714/100, 714 1- 21, 714/48, 714/41, 713/100, 713161-162, 713/168, 713170-171
• US Class Current: 455/433
• CPC Class Codes: H04W 24/02 Arrangements for optimising operational condition

Abstract

The present invention is a method and system for updating location information of mobile stations. A mobile station moves from an area controlled by a first mobile services switching center (MSC) to an area controlled by a second MSC. The mobile station then registers with the second MSC, and, in response, the mobile station is added to a second MSC database. The second MSC recalculates a second MSC checksum to include the newly registered mobile station. Next, the HLR sends an HLR checksum to the second MSC. The second MSC compares the HLR checksum and the second MSC checksum. If the checksums are equal, then the second MSC sends the location registration signal to the mobile station. If the checksums are unequal, then the second MSC sends an error signal to the HLR, and also sets the second MSC database equal to a previous correct database. Next, the HLR sends all logged erasures to the second MSC. The second MSC then appropriately subtracts and adds each erased and newly registered mobile station to the database of the second MSC and recalculates the second MSC checksum until both checksums are equal.

Claims

1. A method in a first mobile services switching center for updating location information of a mobile station, said method comprising:

sending a home location register checksum from a home location register to said first mobile services switching center;

subtracting said mobile station from the first mobile services switching center database;

recalculating the first mobile services switching center checksum to account for the subtracted mobile station;

sending an erasure acknowledge signal from said first mobile services switching center to said home location register; and

comparing said first mobile services switching center checksum to said home location register checksum.

2. The method of claim 1, wherein said step of comparing said first mobile services switching center checksum to said home location register checksum further comprises the additional steps of:

sending a negative acknowledge signal from said first mobile services switching center to said home location register when said home location register checksum and said first mobile services switching center checksum are not equal;

setting said first mobile services switching center database equal to a previous correct database when said home location register checksum and said first mobile services switching center checksum are not equal;

sending all logged mobile stations that have been erased from said home location register to said first mobile services switching center after receiving said error signal at said home location register from said first mobile services switching center;

subtracting each erased mobile station and adding each newly registered mobile station to said previous correct database;

appropriately adding and subtracting each of said mobile stations until said home location register checksum and said first mobile services switching center checksum are equal;

erasing the mobile stations that are resent in said logged erasures; and

stopping said sending of a negative acknowledge signal from said first mobile services switching center to said home location register when said first mobile services switching center checksum and said home location register checksum are equal.