VHASH Security.

VHASH is an almost-delta-universal hash family, designed for exceptional performance on computers that multiply 64-bit quantities efficiently. Changes to thealgorithm detailed in this note improve both security and performance over the original 2006 version. Speed is improved through a newly analyzed hash construction which allows the use of lower-degree polynomials. Claimed security is higher due primarily to improved analysis and a change in prime modulus. The result is a hash family capable of hashing cache-resident one kilobyte messages on the Intel Core 2 architecture at a rate of about one-half processor cycle per byte of message with a collision probability of less than 1/261.