With the Lock transactions command, the accounting transactions are blocked and marked with control codes that can certify, over the years, that the transactions have not been modified. This method (US Patent No. 7,020,640), based on electronic signature, guarantees one of the highest levels of data integrity since it can demonstrate with no doubt that the accounting has not been altered, as international laws prescribe.
Date of new lock (inclusive)
Specify the date up until when the transactions will be locked.
It is possible to insert a password to eventually unlock the transactions or to carry out a new lock in the future.
If the program finds no errors in the transactions included in the lock date, it will lock the transactions, calculate and assign individual numbers and codes to each row of transactions which can be viewed in the Lock view on the Transactions table.
The data of the following fields are automatically filled by the program based on the last executed lock.
A "Yes" is shown if the lock is valid.
Date of lock
The date of the last executed lock is shown.
It's the value automatically entered by the program in the last row of the LockNum column.
When the lock is repeated, if the value of the last row lock number is unchanged, it means that the lock is valid and that data has not been altered; if however the value is changed, the program shows the following codes:
- (-1) if the lock is invalid from the first row
- (-2) if there are rows that have the same LockNum.
This is the control code present in the last transaction.
By confirming with the OK button, the lock information window will automatically show.
All data in this window are automatically inserted by the program.
The program will recalculate the controls codes (hashes) and will verify if they correspond to the ones related to the transactions. If the codes correspond the lock is valid, if not, it means that changes have been made and the lock is not valid.
All information related to the file creation are shown.
All information related to the transaction lock are shown (use, valid)
All transactions until the indicated data are locked and checked by a series of counters.
- LockNum: the progressive number that identifies the row
- LockAmt: the cumulative transactions total, similar to the total at the end of the page, as required by some national regulations
- LockProg: electronic signature (Hash MD5) that is the unique identification of all the transactions up to the point of entry.
Control code (Hash Md5)
This is the main element of the certification, which takes the following into account:
- The contents of the current entry
- The contents of all the preceding transactions
- The progressive number (LockNum)
- The cumulative balance (LockAmt)
The control number is different if the accounting data undergo even the slightest modification (a date or an amount is changed). If the control number remains the same, this means that the data are original and therefore have not been changed.
The program automatically inserts the values in this section.
Recording the certification number
Once the transactions in the period have been locked, it is enough to print the last certified row with the relevant certification number (LockProg) and to store this information in a safe place. If the certification number remains unchanged over time, it means that the data have not been modified. Before launching a new lock, verify the data of the previous lock by recalling the Lock transactions command from the Account2 menu.
The Unlock transactions command removes the lock and the control hashes. If the lock was set with a password it will be necessary to type the password in order to remove the lock.
If later on you want to relock the transactions, if they have not been modified, the lock hashes will be the same; if however some data has been changed, the control hashes will be different.
Some time ago, Banana.ch requested the auditing firm Ernst&Young to analyze this certification method and the firm approved and certified it as being in compliance with Swiss and German laws.
- Document related to Swiss certification (PDF in German)
- Document related to German certification (PDF in German)
The accounting data are always accessible even after long periods of time.
Banana Accounting allows all the accounting data to be exported to Html e Xml. The generated file may be saved on a CD and accessed on any computer even after many years, even by persons who do not have the Banana Accounting software.
Related document: Archiving in Html and XML