problems To understand the class of polynomial-time solvable problems, we must first have a formal notion of what a "problem" is. We define an abstract problem Q to be a binary relation on a set I of… (More)

An encryption method is presented with the novel property that publicly revealing an encryption key does not thereby reveal the corresponding decryption key. This has two important consequences: (1)… (More)

We present a digital signature scheme based on the computational difficulty of integer factorization. The scheme possesses the novel property of being robust against an adaptive chosen-message… (More)

Like many technologies, low-cost Radio Frequency Identification (RFID) systems will become pervasive in our daily lives when affixed to everyday consumer items as “smart labels”. While yielding great… (More)

This document describes the RC5 encryption algorithm, a fast symmetric block cipher suitable for hardware or software implementations. A novel feature of RC5 is the heavy use of data-dependent… (More)

The MD4 message digest algorithm takes an input message of arbitrary length and produces an output 128-bit "fingerprint" or "message digest", in such a way that it is (hopefully) computationally… (More)

In this paper we formalize the notion of a ring signature, which makes it possible to specify a set of possible signers without revealing which member actually produced the signature. Unlike group… (More)

1 Introduction ~Ve present two simple micropayment schemes, "PayWord" and :'MicroMint," for making small purchases over the Internet. We were inspired to work on this problem by DEC's "Millicent"… (More)