NL-DHT: A Non-uniform Locality Sensitive DHT Architecture for Massively Multi-user Virtual Environment Applications

DHT networks offer a scalable structure for use in massively multi-user virtual environments (MMVEs). However, an issue with DHT structures is their use of uniform location-independent ID assignment. This conflicts with the locality-sensitive non-uniform ID assignment needed to achieve efficient latency-aware routing in MMVE applications. Our proposed solution is to use a modified version of the Hilbert space-filling curve in order to map users¿ locations from three dimensional VE space into single dimensional DHT ID space in the best locality preserving way. The need for such modified Hilbert curve is due to the fact that users are not typically homogeneously distributed in MMVEs while Hilbert curves fill space in a uniform manner. Generation of, and mapping to, an entire Hilbert curve can be very expensive in terms of computational complexity. Thus we present a fast dynamic mapping of MMVE locations to the modified Hilbert curve to reduce the mapping complexity.