A standard universal identifier (SUI) is a systematically assigned label that, theoretically at least, distinguishes a person from all others. If the labels assigned by a universal identification scheme are to fulfill this function, each SUI must meet all the following criteria:
UNIQUENESS. It must be unique for each person. No more than one person can be assigned the same SUI, and each person must have no more than one SUI.
PERMANENCE. It must not change during the life of an individual and should not be re-used after his death until all records concerning him have been retired.
UBIQUITY. Labels must be issued to the entire population for which unique identification is required.
AVAILABILITY. It must be readily obtainable or verifiable by anyone who needs it, and quickly and conveniently regainable in case it is lost or forgotten.
INDISPENSABILITY. It must be supported by incentives or penalties so that each person will remember his SUI and report it correctly; otherwise systems will become clogged with errors.
ARBITRARINESS. It must not contain any information. If it does, e.g., State of issuance, it will be longer than necessary, thus violating the "brevity" criterion (see below). It may also violate the "permanence" criterion if changeable items, such as name or address, are incorporated. Most important, if items of personal information are part of an SUI, they will be automatically disseminated whenever the SUI is used; in our view, this would be undesirable.
BREVITY. It must be as short as possible for efficiency in recognition, retrieval, and processing by man or machine.
RELIABILITY. It must be constructed with a feature that detects errors of transcription or communication.2 If the communication of SUIs were done entirely by machine, errors could be minimized through technology, but short of this, there must be protection against the risk of human error in writing or reciting an SUI. For the foreseeable future, the need will continue for people to fill out forms and to report information themselves.