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Comment by tptacek | Hacker News Reader

You don't need elliptic curve to get forward secrecy from TLS; the ECC ciphersuites are very new, but the ephemeral Diffie-Hellman construction in TLS has been around for a long time.

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Unfortunately, though, plain DHE is really slow, so it's pretty hardware-intensive to do it at scale, and to keep latency manageable. Google made a big deal out of moving to ECDHE the year before last, and part of that was that it allowed them to get perfect forward secrecy without sacrificing performance.

This was _the_ thing I was looking forward to most in the release of Debian 7. A sufficiently recent version of OpenSSL to do ECDHE.

Plain DHE is _killing_ our first load times...

I got this included into Ubuntu 12.04 and later. You might want to consider running Ubuntu just as a termination host if you are really desperate.

We just went through some similar stuff, having to ditch Amazon Linux for our SSL termination machine because Red Hat strips out all elliptic-curve crypto. It might also be worth investigating whether or not the Debian 7 OpenSSL build includes the optimized 64-bit ECDHE implementation contributed by Google, which wasn't enabled in Ubuntu's build until last month.

Yer welcome =)

I pestered peeps till they turned that flag on. As you said, it's now on for Ubuntu.

Belated thanks!

Can you please expand on this? Does using TLS (vs SSL2v3) automatically ensure you're using ephermal diffie hellman?

No, it's a ciphersuite; the server and client have to agree to use it.

No.

You can't control the client but you can have the server offer up a preferred list of ciphers.

On nginx, this would be ssl_prefer_server_ciphers = on; for example

These may be useful

https://www.ssllabs.com/ssltest/

https://www.ssllabs.com/projects/best-practices/

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