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Pseudonymous Identity

Classification Key : Exterior Security, Information Disclosure


Anonymity targets can be personal or impersonal, but everything has some form of identity. The identity of a person is a name, the identity of a packet is by the information in its header, as well as the payload, the identity of a data entry in a database is by its primary key, etc. If identities are left exposed, entities are exposed too.
How can entities be saved from exposure?


Hide identity by adopting a random pseudonym that does not relate to the original. Store the pseudonym assignment because the inverse assignment is also required. Protect the pseudonym assignment, because the success of a pseudonym depends on its secrecy.

Known Uses

Anonymity targets and pseudonyms vary based on the underlying problem domain. For anonymous web interactions,a packet header is an anonymity target because it contains metadata about packet senders. A proxy can be used between a request sender and a recipient to strip header information (e.g., HTTP_USER_AGENT) and submit on behalf of the sender. This is followed by well-known anonymizing tools such as Anonymizer and iProxy.
In location based systems and VANETs,user agents are hidden behind a pseudonym. Some VANETs, e.g., Amoeba [55], form a group containing nearby vehicles and use another layer of pseudonym to identify the group. Another anonymity target is the location of a user agent.

Related Patterns

Morphed Representation


Hafiz Privacy Patterns


Anonymity, Privacy


Last modified: May 05, 2012

Conceived and Maintained by: Munawar Hafiz