A Flags Extension for TLS 1.3

Document Type Replaced Internet-Draft (tls WG)
Author Yoav Nir 
Last updated 2019-08-08 (latest revision 2019-07-23)
Replaced by draft-ietf-tls-tlsflags
Stream Internet Engineering Task Force (IETF)
Intended RFC status (None)
Expired & archived
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Stream WG state Adopted by a WG
Document shepherd No shepherd assigned
IESG IESG state Replaced by draft-ietf-tls-tlsflags
Consensus Boilerplate Unknown
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This Internet-Draft is no longer active. A copy of the expired Internet-Draft can be found at


A number of extensions are proposed in the TLS working group that carry no interesting information except the 1-bit indication that a certain optional feature is supported. Such extensions take 4 octets each. This document defines a flags extension that can provide such indications at an average marginal cost of 1 bit each. More precisely, it provides as many flag extensions as needed at 4 + the order of the last set bit divided by 8.


Yoav Nir (ynir.ietf@gmail.com)

(Note: The e-mail addresses provided for the authors of this Internet-Draft may no longer be valid.)