The question says..... What correctly defined "data integrity"? A. It guarantees that your confidential files are kept on your webserver B. It guarantess that only specific set of users may access your confidential files. C. it guarantess that delivery of your confidential files will not be read by malicious user. D. It guarantees that delivery of your confindential files will not be altered during transmission. E. It guarantees that access to your confidential files will prompt the user for their password of the web browers. Tell me why the answer to this question is D.
Why the answer is not D? If you think D is wrong, which answer you think it is correct? Data Integrity means that the data sent through the network, must be assured that the content has not been modified by third party. Think about it, confidentiality does not necessary mean data integrity. For example, A sends a private message M to B. A uses B's public key to encrypt the message M, so that only B can view it. However, there is a bad guy, C, catches that encrypted message, and throw it away. C then create another message M', use B's public key to encrypt the message M' and pretent that the message is sent by A. Thus, the message content is changed from M to M', but C has no way to know the confidential content that A sends B. Nick