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RFC 9170

Long-Term Viability of Protocol Extension Mechanisms, December 2021

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M. Thomson

T. Pauly

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DOI:  10.17487/RFC9170

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The ability to change protocols depends on exercising the extension and version-negotiation mechanisms that support change. This document explores how regular use of new protocol features can ensure that it remains possible to deploy changes to a protocol. Examples are given where lack of use caused changes to be more difficult or costly.

For the definition of Status, see RFC 2026.

For the definition of Stream, see RFC 8729.