A Universally Unique Identifier (UUID) is a 128-bit label used for information in computer systems. The term Globally Unique Identifier (GUID) is also used, mostly in Microsoft systems.
When generated according to the standard methods, UUIDs are, for practical purposes, unique. Their uniqueness does not depend on a central registration authority or coordination between the parties generating them, unlike most other numbering schemes. While the probability that a UUID will be duplicated is not zero, it is generally considered close enough to zero to be negligible.
Thus, anyone can create a UUID and use it to identify something with near certainty that the identifier does not duplicate one that has already been, or will be, created to identify something else. Information labeled with UUIDs by independent parties can therefore be later combined into a single database or transmitted on the same channel, with a negligible probability of duplication.
Adoption of UUIDs is widespread, with many computing platforms providing support for generating them and for parsing their textual representation.
In the 1980s Apollo Computer originally used UUIDs in the Network Computing System (NCS). Later, the Open Software Foundation (OSF) used UUIDs for their Distributed Computing Environment (DCE). The design of the DCE UUIDs was partly based on the NCS UUIDs, whose design was in turn inspired by the (64-bit) unique identifiers defined and used pervasively in Domain/OS, an operating system designed by Apollo Computer. Later, the Microsoft Windows platforms adopted the DCE design as "Globally Unique IDentifiers" (GUIDs).
registered a URN namespace for UUIDs and recapitulated the earlier specifications, with the same technical content.
When in July 2005 was published as a proposed IETF standard, the ITU had also standardized UUIDs, based on the previous standards and early versions of .
UUIDs are standardized by the Open Software Foundation (OSF) as part of the Distributed Computing Environment (DCE).
This page is automatically generated and may contain information that is not correct, complete, up-to-date, or relevant to your search query. The same applies to every other page on this website. Please make sure to verify the information with EPFL's official sources.
A surrogate key (or synthetic key, pseudokey, entity identifier, factless key, or technical key) in a database is a unique identifier for either an entity in the modeled world or an object in the database. The surrogate key is not derived from application data, unlike a natural (or business) key. There are at least two definitions of a surrogate: Surrogate (1) – Hall, Owlett and Todd (1976) A surrogate represents an entity in the outside world. The surrogate is internally generated by the system but is nevertheless visible to the user or application.
A binary number is a number expressed in the base-2 numeral system or binary numeral system, a method of mathematical expression which uses only two symbols: typically "0" (zero) and "1" (one). The base-2 numeral system is a positional notation with a radix of 2. Each digit is referred to as a bit, or binary digit. Because of its straightforward implementation in digital electronic circuitry using logic gates, the binary system is used by almost all modern computers and computer-based devices, as a preferred system of use, over various other human techniques of communication, because of the simplicity of the language and the noise immunity in physical implementation.
In mathematics and computing, the hexadecimal (also base-16 or simply hex) numeral system is a positional numeral system that represents numbers using a radix (base) of sixteen. Unlike the decimal system representing numbers using ten symbols, hexadecimal uses sixteen distinct symbols, most often the symbols "0"–"9" to represent values 0 to 9, and "A"–"F" (or alternatively "a"–"f") to represent values from ten to fifteen. Software developers and system designers widely use hexadecimal numbers because they provide a human-friendly representation of binary-coded values.
Le cours donne une introduction à la théorie des EDO, y compris existence de solutions locales/globales, comportement asymptotique, étude de la stabilité de points stationnaires et applications, en pa
Independent modeling of various modules of an information system (IS), and consequently database subschemas, may result in formal or semantic conflicts between the modules being modeled. Such conflicts may cause collisions between the integrated database s ...
2019
, ,
A gaze-driven methodology for discomfort glare was developed and applied for glare evaluation. A series of user assessments were performed in an office-like test laboratory under various lighting conditions. The participants’ gaze responses were recorded b ...
Organocatalysis has evolved significantly over the last decades, becoming a pillar of synthetic chemistry, but traditional theoretical approaches based on quantum mechanical computations to investigate reaction mechanisms and provide rationalizations of ca ...