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Re: ALPN in ClientHello for protocols other than HTTP?

From: TJ Saunders <>
Date: Wed, 18 May 2016 09:20:38 -0700

> > It is now; I've requested of IANA that "ftp" be registered as one of the
> > accepted ALPN extension names; see:
> Ah, neat. Our code is too hardcoded for the HTTP variations for ALPN still
> though so in our case holding off ALPN for ftp makes sense. And I guess
> ftp is there more for completeness rather than ftp servers actually offering
> multiple protocols behind TLS.

Technically it'd be possible to offer SFTP over TLS (rather than over
SSH); an FTP server might also offer rsync over TLS. But those, I
think, would be quite rare.

I added support for "ftp" as an NPN/ALPN to ProFTPD's mod_tls module
strictly to enable Chrome's TLS False Start when making TLS connections
(and hopefully make for less latent FTP data transfers), per:

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Received on 2016-05-18