Re: [Uta] Robert Wilton's Discuss on draft-ietf-uta-rfc7525bis-09: (with DISCUSS and COMMENT)

[Peter Saint-Andre <[e-mail]>]

On 7/19/22 10:44 AM, Peter Saint-Andre wrote:
> One more small note below...
> 
> On 7/19/22 10:30 AM, Rob Wilton (rwilton) wrote:
> 
> <snip/>
> 
>> You may want to consider whether it is worth making it clearer, either 
>> in the titles or the first intro paragraph, in section of 3.1.1/3.1.2 
>> that the protocol version requirements are specifically about 
>> implementations, and deployments are allowed/encouraged to restrict 
>> deployments to later TLS versions where reasonable/appropriate.  
>> Otherwise, I suspect that readers may well have both implementations 
>> and deployments in their head when they read this section.
> 
> Good point. I'll look at the entire document again from this perspective 
> and see where we might add some clarifying text.

I found a good place for some amplifying text, at the end of the 
following paragraph in the introduction.

OLD

    These are minimum recommendations for the use of TLS in the vast
    majority of implementation and deployment scenarios, with the
    exception of unauthenticated TLS (see Section 5).  Other
    specifications that reference this document can have stricter
    requirements related to one or more aspects of the protocol, based on
    their particular circumstances (e.g., for use with a particular
    application protocol); when that is the case, implementers are
    advised to adhere to those stricter requirements.  Furthermore, this
    document provides a floor, not a ceiling, so stronger options are
    always allowed (e.g., depending on differing evaluations of the
    importance of cryptographic strength vs. computational load).

NEW

    These are minimum recommendations for the use of TLS in the vast
    majority of implementation and deployment scenarios, with the
    exception of unauthenticated TLS (see Section 5). Other
    specifications that reference this document can have stricter
    requirements related to one or more aspects of the protocol, based on
    their particular circumstances (e.g., for use with a particular
    application protocol); when that is the case, implementers are
    advised to adhere to those stricter requirements. Furthermore, this
    document provides a floor, not a ceiling: where feasible,
    administrators of services are encouraged to go beyond the minimum
    support available in implementations to provide the strongest
    security possible. For example, based on knowledge about the deployed
    base for an existing application protocol and a cost-benefit analysis
    regarding cryptographic strength vs. computational load, a given
    service provider might decide to disable TLS 1.2 entirely and offer
    only TLS 1.3.

See https://github.com/yaronf/I-D/pull/469/files

Peter