Defending one-time pad cryptosystems from denial-of-service attacks

Abstract

A one-time pad (OTP) can be conceived of as a stream cipher where the plaintext and key have equal length and the key is never reused. This cipher has easily proven properties of deniability and mathematical unbreakability, even in situations where an eavesdropper has access to unlimited computing power. Yet OTPs also have non-intuitive bottlenecks in CPU, RAM, disk I/O, and key material consumption, particularly when OTPs protect their own communication metadata (such as the volume of information exchanged) in the presence of random packet injection attacks, link failures, and endpoint outages. This paper explains how these problems arise and presents a set of countermeasures that treats them effectively and scalably.