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Re: [TLS] Record header size?

Peter Gutmann <pgut001@cs.auckland.ac.nz> Wed, 18 November 2015 01:41 UTC

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From: Peter Gutmann <pgut001@cs.auckland.ac.nz>
To: "Short, Todd" <tshort@akamai.com>, Eric Rescorla <ekr@rtfm.com>
Thread-Topic: [TLS] Record header size?
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Date: Wed, 18 Nov 2015 01:41:32 +0000
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Subject: Re: [TLS] Record header size?
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Short, Todd <tshort@akamai.com> writes:

>To be honest, it’s always kinda bugged me that SSL/TLS uses a 5-byte header,
>coming from my embedded network system background.
>
>[...]

+1.  I wrote about this problem years ago in "Performance Characteristics of
Application-level Security Protocols",
https://www.cs.auckland.ac.nz/~pgut001/pubs/app_sec.pdf, see the section
"Interaction with Encryption Hardware" for more.  It doesn't name any names
since I could only use public sources, but was based on discussions with
hardware vendors.

Mind you, TLS is almost pleasant compared to the crazy calisthenics you have
to go through to deal with SSH data.  You basically can't do SSH's crypto
efficiently...

Peter.

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