Identity Attributes


Identity Attributes are attributes or properties of an Entity (or Digital Identity or even a Digital Subject) that may have zero or more values.

Identity Attributes should be Attributes that within the current context can be used to indicate a specific Digital Identity. Otherwise, they are just Attributes.


The Natural Person (i.e. Entity) Bob Smith might be represented as a Digital Subject in the Context of his employer, the Port Control Authority. This Digital Subject might have the following types of Identity Attributes (and associated values) in this context:[1]
  • email-address = bob@portcontrol.gov
  • phone number = 617-555-1234
  • passport information = ...etc.
  • fingerprint data = ...etc.

This same Entity Bob Smith is also represented as a Digital Identity in a "customer-to-Clothes-R-Us" Context (this customer's relationship with the Clothes-R-Us merchant. In this Context Bob has these Identity Attributes:

  • platinumCustomer
  • preferredColor = "blue"
  • shirtSize = L

In Higgins[2]#


In Higgins a Identity Attributes is identified by a URI that defines its type. The URI
might indicate an Identity Attribute that represented a person's Last Name. The schema associated with the containing Context provides metadata about this URI.


  • An Identity Attributes may have zero or more values
  • The values may be literal types (defined by the XML Schema literal types) or complex (structured) values
  • A special kind of Identity Attributes is called a Subject Relationship whose value is a reference to another Digital Subject in the same or a different Context
  • Some Identity Attributes are defined by the containing Context's schema to allow multiple unique values. For example the attribute preferredBreakfast
    • might have the values {spam, eggs},
    • but it could not have the values {spam, spam, spam, eggs, spam}.

More Information#

There might be more information for this subject on one of the following: