Re: [TLS] Data volume limits

Ilari Liusvaara <ilariliusvaara@welho.com> Fri, 01 January 2016 19:28 UTC

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Date: Fri, 1 Jan 2016 21:27:57 +0200
From: Ilari Liusvaara <ilariliusvaara@welho.com>
To: James Cloos <cloos@jhcloos.com>
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Subject: Re: [TLS] Data volume limits
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On Fri, Jan 01, 2016 at 02:00:07PM -0500, James Cloos wrote:
> [Msg for followup picked at random from this thread -JimC]
> 
> One thing we should remember on this thread is that it does not only
> apply to aes and its' 128-bit block size.
> 
> Because TLS chose to create a NotQuiteChaCha rather than use ChaCha,
> its chacha20poly1305 also has a small data volume limit (2^40 bits;
> only twice aesgcm's limit).

Huh? AFAIK, the limiting factor with Chacha20 as specced in TLS is
the RSN space => 2^64 records maximum (which is 256ZB at max record
size, and 352EB just to transmit the record overheads).


Transferring just the 352EB at 1,000 Gbps would take about 100 years.


-Ilari