RFC 8645 · INFORMATIONAL · 2019

Re-keying Mechanisms for Symmetric Keys

Overview

RFC 8645, “Re-keying Mechanisms for Symmetric Keys”, is an Informational document published in August 2019 by S. Smyshlyaev. The canonical text is published by the RFC Editor.

Abstract

A certain maximum amount of data can be safely encrypted when encryption is performed under a single key. This amount is called the "key lifetime". This specification describes a variety of methods for increasing the lifetime of symmetric keys. It provides two types of re-keying mechanisms based on hash functions and block ciphers that can be used with modes of operations such as CTR, GCM, CBC, CFB, and OMAC.

This document is a product of the Crypto Forum Research Group (CFRG) in the IRTF.

Abstract as published in the RFC, via rfc-editor.org.

What “Informational” means

Published for the general information of the community. It does not define an IETF standard and carries no standards-track status.

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