Re: [TLS] Kathleen Moriarty's Yes on draft-ietf-tls-cached-info-20: (with COMMENT)

Kathleen Moriarty <kathleen.moriarty.ietf@gmail.com> Thu, 17 December 2015 15:22 UTC

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Date: Thu, 17 Dec 2015 10:22:04 -0500
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From: Kathleen Moriarty <kathleen.moriarty.ietf@gmail.com>
To: Stephen Farrell <stephen.farrell@cs.tcd.ie>
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Cc: draft-ietf-tls-cached-info@ietf.org, The IESG <iesg@ietf.org>, tls@ietf.org, tls-chairs@ietf.org
Subject: Re: [TLS] Kathleen Moriarty's Yes on draft-ietf-tls-cached-info-20: (with COMMENT)
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On Thu, Dec 17, 2015 at 10:09 AM, Stephen Farrell
<stephen.farrell@cs.tcd.ie> wrote:
>
>
> On 17/12/15 14:58, Kathleen Moriarty wrote:
>> Kathleen Moriarty has entered the following ballot position for
>> draft-ietf-tls-cached-info-20: Yes
>>
>> When responding, please keep the subject line intact and reply to all
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>> introductory paragraph, however.)
>>
>>
>> Please refer to https://www.ietf.org/iesg/statement/discuss-criteria.html
>> for more information about IESG DISCUSS and COMMENT positions.
>>
>>
>> The document, along with other ballot positions, can be found here:
>> https://datatracker.ietf.org/doc/draft-ietf-tls-cached-info/
>>
>>
>>
>> ----------------------------------------------------------------------
>> COMMENT:
>> ----------------------------------------------------------------------
>>
>> Just a quick comment, sorry for asking this late and I won't hold up on
>> it either, just want to raise the question without quite enough time to
>> research it all.
>>
>> I see the SHA-256 truncation is just 32 bits.  In other applications,
>> about half is what is typically recommended.  I know you are trying to
>> cut on space, but will problems arise from this shorter value?
>
> Nah, I think this one's ok. IIUC, the result of a collision is
> just a handshake fail, and then presumably recovery when they
> ditch the cached stuff. Section 5 describes this.

OK, no hold up on it, there just wasn't an explanation in the draft as
to why 32 bits was enough in section 5 (or any other).

Thanks,
Kathleen

>
> S.
>
>
>>
>>



-- 

Best regards,
Kathleen