Privacy

Definition

The security quality subfactor, privacy, is the degree to which sensitive identifications, data, and communications is kept secret from unauthorized individuals, organizations, and applications.

Types

Privacy can be subtyped into:

• Anonymity
• Confidentiality

Guidelines

The following guidelines have been found to be useful when producing privacy requirements:

• Privacy is typically maintained because disclosure could result in physical or financial harm, embarrassment, inconvenience, or unfairness to some individual or organization.
• Privacy are related to, but go beyond, authorization because people and applications should have access only to the data and communications for which they are authorized.
• Privacy must be consistent with any associated privacy statement.
• Privacy may involve certain legal constraints such as laws that require certain data (e.g., credit card information, health care information) to be kept private.
• Privacy must be consistent with auditability, identification, and nonrepudiation, which require users to be identified and information about their interactions to be stored.
  For example, consider a privacy-oriented eMarketplace application that acts as an intermediary between buyers, merchants, and a credit card authorization processing gateway. The buyers may not want to provide private personal information (e.g., their name, billing address, credit card number and expiration date) to merchants who do not really need it if they are not going to be the ones to obtain purchase authorizations from the credit card authorization processors. Note that electronic wallets undermine privacy because they make it easy for buyers to supply private information to merchants. Instead, the eMarketplace strongly supports privacy by:
  • Hiding private customer personal information from merchants.
  • Authorizing the credit card purchase for the buyer (which is why the merchant wants the private information).
  • Only suppling the merchant with the non-private information (e.g., delivery address and credit payment information such as credit approval).
  • Strongly encrypting all communications and storage of private information.