Fig. 9.3.4 Encrypting a field of data.There are many issues that relate to encryption. Some of the issues are as follows:
- How secure is the encrypting algorithm
- Who can decrypt the data
- Should fields that need to be indexed be encrypted
- How should decryption keys be protected
- And so forth
One of the more interesting issues is consistency of encryption. Suppose you encrypt the
name “Bill Inmon.” Suppose that at later place, you need to once again encrypt the name
—Bill Inmon. You need to ensure that the name—Bill Inmon—is encrypted the same
everywhere there is a need for encryption. You need to ensure consistency of encryption
everywhere encryption is needed. This is necessary because if you need to link records
based on an encrypted value, you cannot do so if there is no consistency of encryption.
Fig. 9.3.5 shows the need for consistency of encryption.
Fig. 9.3.5 Consistency of encryption is an issue.Chapter 9.3: Repetitive Analysis