Digital Identity

Anonymity and Pseudonymity

One of the questions that your business should understand clearly is what level of identity is needed for which relationships. For many purposes, you need specific, authenticated, and detailed identity information from your partners, suppliers, and employees. You may be able to provide service to customers, however, as they remain anonymous or at least pseudonymous.

True anonymity is not realistic for most online services, since they probably have to at least maintain some kind of user state and that requires telling which individual HTTP requests are related. Consequently, the user is not anonymous, because you can distinguish between different users. This leads to the concept of pseudonymity .

In a pseudonymous system, users are uniquely identified, but other identifying information is not shared. Pseudonymous systems give subjects a unique ID with which attributes, rights, and privileges can be associated. Pseudonymity is a term usually reserved for people, since the unique ID and its associated attributes, rights, and privileges constitute an identity as we've defined it. Pseudonymity implies that this identity cannot be tied to other identities that the subject might have without the subject divulging the connection.

Businesses should ask, "What identifying information is required?" early in the design process for an online service. I say "businesses" because this is almost always a business decision, not a technology decision. In keeping with our concept of the privacy policy being a term sheet for an identity transaction, each piece of the customer's identity that is being requested should also be associated with the need for the data as well as the benefit that the customer will receive by giving the data.

This rule is not followed as often as it should be. You've probably been to web forms that ask you for more data than you think the company needs to provide the service. You probably resented it. Adding insult to injury, it's likely that the company collecting the data never made any use of it whatsoever, whether for your benefit or not. Collecting unnecessary data alienates customers and clutters forms, so don't do it.