Also see the references listed in the seminar notes . But we no longer use computers only for large central databases, so there are new risks to privacy, but also new tools to enhance privacy. Postmasters managing e-mail in a company have a duty to the company.
Companies can read legally employee's e-mail in many countries.
There are regulations that restrict police the conditions under which police can open post in most countries. Few have yet passed specific laws or regulations to set up procedures for intercepting e-mail. So we rely on judges interpretations' of old laws, or ISPs and local police agreeing some local practice. Hierarchical certification Association certifies certifying officer in each member. Other PETs Steganography most cipher text doesn't look like ordinary text so people can tell you have used encryption, and single out your messages for attention steganography hides one message inside a larger innocent message, e.g. a picture containing subtle, invisible colour variations that represent a hidden message.