Data Currency is information relevant or pertaining to determining the "freshness" of the specified data
Last Update contains information on the date and time when the data was last refreshed. The age of the data can be derived from this metadata
value. Last Update also allows RPs
to determine the currency of the data, and whether the data was refreshed recently enough to be used in a particular transaction.
Attribute values sent from an AP to an RP may only be valid for its defined use for a set amount of time, depending on requirements, policy, or legal factors. The date after which an attribute's value is considered no longer valid for its defined use is the Expiration Date. Though Expiration Date and Last Update both allow an RP to determine if an attribute’s value is current and sufficient, Expiration Date (exp
) differs from Last Update in that there is a specified date or threshold after which the data becomes void for its defined use. RPs
have the freedom to accept attributes after they have been considered expired for their original intended use, but this decision is made at their own discretion based upon the intended use of the attribute value, the type of interaction it is supporting, and the environment in which they operate. For example, an RP may choose to accept a recently expired driver’s license number for access to a low assurance service. However, it is unlikely that an agency would accept a lapsed security clearance for access to classified data.
may not trust certain attribute values unless they've been verified within a certain time period. This is particularly true for certain attribute values such as security clearance, where the original established date of the value alone may not be sufficient for granting access to national security systems or data. Last Verification provides the most recent date and time at which the value was verified as true and belonging to the specified individual. This metadata focuses on the last date that verification occurred, and does not include any information about methods of verification.
There might be more information for this subject on one of the following: