For ITU-T purposes, the identity asserted by an entity represents the uniqueness of that entity in a specific context and is not intended to indicate positive validation of a person.
Identity management (IdM) is the process of secure management of identity information (e.g., credentials, identifiers, attributes, and reputations). IdM is a complex technology that includes: establishing, modifying, suspending, archiving or terminating identity information; recognizing partial identities that represent entities in a specific context or role; establishing and assessing trust between entities; and the discovery (location) of an entity’s identity information (e.g., authoritative identity provider (IdP) that is legally responsible for maintaining identifiers, credentials and some or all of the entity’s attributes.
The attributes by which an entity is described, recognized or known (ITU-T)
The fundamental concept of uniquely identifying an object (person, computer, etc.) within a context. (OpenGroup)
A set of claims made by one party about another party. Claims are typically conveyed in Signed Security Tokens (Microsoft)
The essence of an entity. One’s identity is often described by one’s characteristics, among which may be any number of identifiers [Liberty & OASIS]