Re: [TLS] TLS 1.2 Long-term Support Profile draft posted

Dave Garrett <> Mon, 21 March 2016 19:42 UTC

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From: Dave Garrett <>
Date: Mon, 21 Mar 2016 15:42:00 -0400
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Subject: Re: [TLS] TLS 1.2 Long-term Support Profile draft posted
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On Monday, March 21, 2016 10:38:43 am Hubert Kario wrote:
> If your hardware really can't do anything better than 2048 bit RSA, it's 
> not LTS, it's a crippled embedded system, and it definitely shouldn't 
> get a stamp of approval "good for next X0 years" or anything similar 
> like a LTS moniker would imply.


Frankly, I think this document should be renamed "Extended Support Profile", rather than "Long-term Support Profile" (and ESP instead of LTS). In anything even approaching the long-term, TLS is dead due to the need for post-quantum crypto, yet to be defined. I'm not even convinced this document is capable of defining a known-good set that can survive for ten years, so that text should really be relaxed significantly. (in this context, 10 years is not "long-term")

The bare minimum anyone should be stating for a 10 year window is something like 3248 bit RSA or ~256 bit ECDSA/EdDSA, and only with the qualifier that upgrades will probably be needed at some point over the next decade. Hardware that can't handle this is not short or medium-term viable, let alone long-term.

Hardware needs to accommodate the viable specifications, not the other way around. If it takes a second or two to perform a handshake, then that's what it takes until it's upgraded/replaced.