Vector-field consistency

Vector-Field Consistency [_{"designation coined by L. Veiga."}] is a consistency model for replicated data (e.g., objects), described in the paper by cite paper | author=Nuno Santos, Luís Veiga, Paulo Ferreira | date=2007 | title=Vector-Field Consistency for Adhoc Gaming| url=http://www.gsd.inesc-id.pt/~lveiga/msc-08-09/vfc-middleware-07.pdf | format=PDF, which was awarded best-paper prize in the ACM/IFIP/Usenix Middleware Conference.

It was initially designed for replicated data management in adhoc 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 games), it needs 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 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 (e.g., players) and field intensity 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.