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Re: [TLS] record layer limits of TLS1.3

Nikos Mavrogiannopoulos <nmav@redhat.com> Wed, 23 November 2016 09:03 UTC

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From: Nikos Mavrogiannopoulos <nmav@redhat.com>
To: Judson Wilson <wilson.judson@gmail.com>
Date: Wed, 23 Nov 2016 10:03:30 +0100
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Subject: Re: [TLS] record layer limits of TLS1.3
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Maybe a solution would be a better maximum fragment length extension
which allows the size can be negotiated in a more fine-grained way, as
pointed in:
https://www.ietf.org/mail-archive/web/tls/current/msg12472.html

I also found these requests asking for larger packet sizes.
https://www.ietf.org/mail-archive/web/tls/current/msg13569.html
https://mailarchive.ietf.org/arch/msg/tls/K_6Ug4GtAxbrQJy2CFFFoxxtJ60

On Wed, 2016-11-23 at 00:46 -0800, Judson Wilson wrote:
> I worry about the buffer sizes required on embedded devices.
> Hopefully the other endpoint would be programmed to limit record
> sizes, but is that something we want to rely on?  This could be a
> parameter agreed upon during the handshake, but that seems bad.
> 
> 
> On Wed, Nov 23, 2016 at 12:41 AM, Nikos Mavrogiannopoulos <nmav@redha
> t.com> wrote:
> > On Wed, 2016-11-23 at 00:39 -0800, Judson Wilson wrote:
> > > Can you send multiple records in one data transfer to achieve
> > > whatever gains are desired? 
> > 
> > The packetization cost still remains even if you do that. However,
> > the
> > question is how does the 2^14 limit comes from, and why TLS 1.3
> > should
> > keep it?
> > 
> > regards,
> > Nikos

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