Re: [TLS] Security concerns around co-locating TLS and non-secure on same port (WGLC: draft-ietf-tsvwg-iana-ports-08)

Richard Hartmann <richih.mailinglist@gmail.com> Mon, 08 November 2010 23:19 UTC

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From: Richard Hartmann <richih.mailinglist@gmail.com>
Date: Tue, 09 Nov 2010 00:19:25 +0100
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Subject: Re: [TLS] Security concerns around co-locating TLS and non-secure on same port (WGLC: draft-ietf-tsvwg-iana-ports-08)
To: Nicolas Williams <Nicolas.Williams@oracle.com>
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On Mon, Nov 8, 2010 at 23:22, Nicolas Williams
<Nicolas.Williams@oracle.com> wrote:

> If the firewall is not close to the client then the client can still
> fallback on no TLS.

True. I understood your example as "if you only allow TLS, an
overloaded port makes things easier for the firewall admin" which I
did not agree with.


> There's trade-offs all over.  I'm not sure that this one is worth all
> that much either way.  I prefer StartTLS over having two ports for
> everything.

I doubt that everyone will rush to register new ports.


>  I might also be happy with forcing TLS on always for new
> ports,

IMO, this is not realistic.


> but I do worry about training users to click through the
> "is this the right server" dialog ("leap-of-faith").

Agreed.


Richard