Tampereing
Threats
Information serves its purpose only if it is available for use by authorized persons in its complete, correct and intact state. Tampering with data and the ensuing loss of integrity can occur in many ways, for example through:
- repeated sending of data with multiple action initiation, for example booking money from a bank account,
- inserting additional message packets into the data stream,
- deleting individual information,
- Deleting command sets
A process is required that assures that a message is not manipulated on its way to the recipient. Encryption alone will not produce the desired success in this case.
However protection is achieved combining encryption with a so-called Hash Function. To illustrate how a Hash Function works imagine that a document is compared by both communication partners letter by letter, it then receives a final sum and is encrypted. The final sum is uniquely characteristic of this document and no other. This final sum is sent with the document. The recipient immediately recognizes any deviations from the original document.