Method and apparatus for synchronizing databases in portable communication devices

• US 6,968,209 B1
• Filed: 02/22/2000
• Issued: 11/22/2005
• Est. Priority Date: 07/05/1999
• Status: Expired due to Fees

• Current Assignee: Telefonaktiebolaget LM Ericsson
• Original Assignee: Telefonaktiebolaget LM Ericsson
• Inventors: Ahlgren, Kristina, Birkler, Jörgen, Gustavsson, Carl, Novak, Lars
• Primary Examiner(s): Hudspeth, David
• Assistant Examiner(s): SMITH, SHEILA B
• Application Number:
  US09/507,685
• Time in Patent Office: 2,100 Days
• Field of Search: 455/558, 455/13.2, 455/466, 455/553, 455/554, 455/550, 455/566, 455/551
• US Class Current: 455/558
• CPC Class Codes: G06F 21/00 Security arrangements for protecting computers, components thereof, programs or data against unauthorised activity
• CPC Class Codes: G06F 21/64 Protecting data integrity, e.g. using checksums, certificates or signatures
• CPC Class Codes: G06F 21/79 in semiconductor storage media, e.g. directly-addressable memories
• CPC Class Codes: H04L 63/123 received data contents, e.g. message integrity
• CPC Class Codes: H04L 67/1095 Replication or mirroring of data, e.g. scheduling or transport for data synchronisation between network nodes
• CPC Class Codes: H04L 69/40 for recovering from a failure of a protocol instance or entity, e.g. service redundancy protocols, protocol state redundancy or protocol service redirection management of faults, events, alarms or notifications in data switching networks H04L41/06
• CPC Class Codes: H04M 1/00 Substation equipment, e.g. for use by subscribers subscriber services or facilities provided at exchanges H04M3/00; prepayment telephone coin boxes H04M17/00; current supply arrangements H04M19/08
• CPC Class Codes: H04M 1/27 Devices whereby a plurality of signals may be stored simultaneously
• CPC Class Codes: H04M 1/274 with provision for storing more than one subscriber number at a time , e.g. using toothed disc
• CPC Class Codes: H04M 1/2745 using static electronic memories, e.g. chips
• CPC Class Codes: H04M 1/27457 Management thereof, e.g. manual editing of data
• CPC Class Codes: H04M 1/275 implemented by means of portable electronic directories
• CPC Class Codes: H04M 1/2757 by data transmission, e.g. downloading
• CPC Class Codes: H04M 1/724 User interfaces specially adapted for cordless or mobile telephones
• CPC Class Codes: H04M 1/725 Cordless telephones user interfaces specially adapted therefor H04M1/724
• CPC Class Codes: Y10S 707/99953 Recoverability
• CPC Class Codes: Y10S 707/99954 Version management

Abstract

A checksum is calculated on a database stored in a SIM card when changes are made to a database stored therein. This checksum can be stored in a mobile phone, e.g., with the change log. When synchronization between devices is to be performed, another checksum can be calculated on the database stored in the SIM card. If the stored checksum does not match the calculated checksum, then a change has occurred in the contents of the database that is not reflected in the change log. Accordingly, a full synchronization process can be performed wherein the database records in each device can be compared. If, on the other hand, the checksums match, then the change log accurately reflects any changes made to the database stored in the SIM card and the synchronization process can proceed more expediently using the change log.

Claims

1. A method for tracking changes to a database stored in a smart card associated with electronic equipment, the method comprising the steps of:

storing, in both a memory of said electronic equipment and said smart card, a checksum associated with said database, wherein said electronic equipment includes a mobile phone;

making a change to said database;

comparing said checksum stored in said memory of said electronic equipment and said checksum stored in said smart card;

calculating, after said change, a modified checksum based on said database;

storing said modified checksum in said memory of said electronic equipment and in said smart card;

logging said change in a chance log in said electronic equipment;

flagging said change log as invalid if said checksums do not match as a result of said comparing step; and

synchronizing said database stored in said smart card with a corresponding database stored in another device using a method which is selected depending upon whether said change log is valid.

2. A method for updating a change log associated with a database stored in a smart card, wherein said smart card is associated with electronic equipment and wherein said electronic equipment includes a mobile phone, the method comprising the steps of:

providing a first memory location and a second memory location for storing a first checksum and a second checksum, respectively;

determining, before a modification is made to said database, if said first and second checksums match;

selectively updating a change log with said modification based on a result of said determining step;

invalidating said change log if said first and second checksums do not match; and

synchronizing said database with a corresponding database stored in another device by comparing each element in said database and said corresponding database.

3. A method for updating a change log associated with a database, the method comprising the steps of:

providing a first memory location and a second memory location for storing a first checksum and a second checksum, respectively;

determining, before a modification is made to said database, if said first and second checksums match;

selectively updating a change log with said modification based on a result of said determining step;

invalidating said change log if said first and second checksums do not match; and

synchronizing said database with a corresponding database stored in another device by comparing each element in said database and said corresponding database, wherein said database is stored in a mobile phone and said another device is a personal computer.