Index-based smart card record backup and recovery method

Abstract

The invention relates to an index-based smart card record backup and recovery method. The index-based smart card record backup and recovery method achieves a backup and recovery function by arranging an index area and a backup area inside a smart card. The index area stores index numbers and is used for computing the write-in address locations of corresponding records. For a specific sort of fixed-length records, when the starting address of a record area is fixed, the index number of every record and the starting address of the record are in a one-to-one relation. The backup area contains a front protection mark, a record length, a currently-latest effective record address, a recovery record address and a rear protection mark. Whether to perform record recovery can be determined according to the protection marks, when new record writing fails and the record recovery is required, a previous effective record can be restored according the two stored addresses and the record length. The index-based smart card record backup and recovery method replaces backup recording with backup indexing, thereby greatly reducing the number of bytes written in during every backup, improving the transaction efficiency of the smart card and reducing the damage rate of the backup area.

Description

Technical field [0001] The invention relates to a method for backup and recovery of records in a smart card, in particular to a method for ensuring the correctness of records in the case of accidental power failure caused by illegal plugging and unplugging. Background technique [0002] IC card is an integrated circuit card with a chip embedded inside. The concept of IC card was first proposed in 1969, and was improved in 1974 and continues to this day. It is a new information carrier with more powerful functions after the magnetic stripe card, which is also called a smart card. [0003] Magnetic stripe cards use magnetic carriers to record data and read and write data through magnetic induction. Unlike magnetic stripe cards, smart cards use semiconductors to store data, and are coded and controlled by logic circuits or microprocessors, and then read and write data through radio frequency interfaces or contact interfaces. The devices in the smart card are all active devices and ...

AI Technical Summary

Problems solved by technology

Although this technology can guarantee the integrity of the data, there are two shortcomings: first, the original record must be backed up every time the record is written, which is equivalent to spending twice the time for writing the record

Due to the slow writing speed of semiconductor memory, in a transaction, the main time consumption comes from data writing, so the time waste caused by backup becomes serious; the second is that the address of the backup area is fixed and the amount of data is large. Records must be re-erased in the backup area and then re-written, resulting in multiple erasing and writing of a large number of blocks in the backup area

This is prone to rapid corruption of the backup area, thus greatly reducing the life of the smart card

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