1. One or more non-transitory computer-readable media for storing network contact information, comprising: a set of m physical memory locations; and one or more virtual vectors each having s virtual memory locations, wherein: each virtual vector is assigned to a corresponding source host; each virtual memory location within each virtual vector is randomly assigned to one or more destination hosts that were contacted by the corresponding source host; and each virtual memory location is randomly and uniformly assigned a corresponding physical memory location from the set of m physical memory locations.