RFC 8547 · EXPERIMENTAL · 2019

TCP-ENO: Encryption Negotiation Option

Overview

RFC 8547, “TCP-ENO: Encryption Negotiation Option”, is an Experimental document published in May 2019 by A. Bittau, D. Giffin, M. Handley, D. Mazieres, E. Smith. The canonical text is published by the RFC Editor.

Abstract

Despite growing adoption of TLS, a significant fraction of TCP traffic on the Internet remains unencrypted. The persistence of unencrypted traffic can be attributed to at least two factors. First, some legacy protocols lack a signaling mechanism (such as a STARTTLS command) by which to convey support for encryption, thus making incremental deployment impossible. Second, legacy applications themselves cannot always be upgraded and therefore require a way to implement encryption transparently entirely within the transport layer. The TCP Encryption Negotiation Option (TCP-ENO) addresses both of these problems through a new TCP option kind providing out-of-band, fully backward-compatible negotiation of encryption.

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

What “Experimental” means

Describes a specification that is part of a research or development effort, published so the community can gain experience with it.

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The canonical text of RFC 8547 is hosted at rfc-editor.org. Available in TXT,HTML.

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