RFC 8439 · INFORMATIONAL · 2018

ChaCha20 and Poly1305 for IETF Protocols

Overview

RFC 8439, “ChaCha20 and Poly1305 for IETF Protocols”, is an Informational document published in June 2018 by Y. Nir, A. Langley. It obsoletes RFC 7539. The canonical text is published by the RFC Editor.

Abstract

This document defines the ChaCha20 stream cipher as well as the use of the Poly1305 authenticator, both as stand-alone algorithms and as a "combined mode", or Authenticated Encryption with Associated Data (AEAD) algorithm.

RFC 7539, the predecessor of this document, was meant to serve as a stable reference and an implementation guide. It was a product of the Crypto Forum Research Group (CFRG). This document merges the errata filed against RFC 7539 and adds a little text to the Security Considerations section.

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.

Read this RFC

The canonical text of RFC 8439 is hosted at rfc-editor.org. Available in TXT,HTML.

Relationships to other RFCs
This RFC obsoletes
RFC 7539
Other RFCs from 2018

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