Vector-Field Consistency_{Designation coined by L. Veiga.} is a

consistency model In computer science, a consistency model specifies a contract between the programmer and a system, wherein the system guarantees that if the programmer follows the rules for operations on memory, memory will be consistent and the results of readi ...

for replicated data (for example, objects), initially described in a paper which was awarded the best-paper prize in the ACM/IFIP/Usenix Middleware Conference 2007. It has since been enhanced for increased scalability and fault-tolerance in a recent paper.{{cite conference , author1=Luís Veiga , author2=André Negrão , author3=Nuno Santos , author4=Paulo Ferreira , year=2010 , title=Unifying Divergence Bounding and Locality Awareness in Replicated Systems with Vector-Field Consistency , book-title = JISA, Journal of Internet Services and Applications, Volume 1, Number 2, 95-115, Springer, 2010 , url=http://www.gsd.inesc-id.pt/~lveiga/vfc-JISA-2010.pdf

Description

This consistency model was initially designed for replicated

data management Data management comprises all disciplines related to handling data as a valuable resource. Concept The concept of data management arose in the 1980s as technology moved from sequential processing (first punched cards, then magnetic tape) to r ...

in ad hoc gaming in order to minimize bandwidth usage without sacrificing playability. Intuitively, it captures the notion that although players require, wish, and take advantage of information regarding the whole of the game world (as opposed to a restricted view to rooms, arenas, etc. of limited size employed in many

multiplayer video game A multiplayer video game is a video game in which more than one person can play in the same game environment at the same time, either locally on the same computing system (couch co-op), on different computing systems via a local area network, or ...

s), they need to know information with greater freshness, frequency, and accuracy as other game entities are located closer and closer to the player's position. It prescribes a multidimensional divergence bounding scheme, based on a vector field that employs consistency vectors k=(θ,σ,ν), standing for maximum allowed time - or replica staleness, sequence - or missing updates, and value_{Since in the Greek alphabet

The Greek alphabet has been used to write the Greek language since the late 9th or early 8th century BCE. It is derived from the earlier Phoenician alphabet, and was the earliest known alphabetic script to have distinct letters for vowels as we ...
there was no letter for the ''vee'' sound, the ''nu'' letter was preferred for its resemblance with the roman V, for ''v''alue, instead of β (''beta'') for the ''vee'' sound in contemporary Greek speaking.} - or user-defined measured replica divergence, applied to all space coordinates in game scenario or world. The consistency vector-fields emanate from field-generators designated as pivots (for example, players) and

field intensity In physics, field strength means the ''magnitude'' of a vector-valued field (e.g., in volts per meter, V/m, for an electric field ''E''). For example, an electromagnetic field results in both electric field strength and magnetic field strength. A ...

attenuates as distance grows from these pivots in concentric or square-like regions. This consistency model unifies locality-awareness techniques employed in message routing and consistency enforcement for multiplayer games, with divergence bounding techniques traditionally employed in replicated database and web scenarios.

Notes

References

Data management