Re: Impact of encryption algorithms on audio

From: David Wagner (daw_at_taverner.cs.berkeley.edu)
Date: 10/12/05


Date: Wed, 12 Oct 2005 04:39:45 +0000 (UTC)


>Could you please let me know whether there are any research works
>containing comparison charts of delay time due to encryption (AES,
>3DES, ECC or some stream ciphers etc) are used on a desktop machine.

A good first-order approximation for symmetric-key algorithms, on
a desktop machine, is "Zero delay". For public-key algorithms --
well, that all depends on the system. Usually you try to set up the
system so that the cost of the public-key computation can be amortized
away.

>How about when it comes to a small chip?

Depends on the chip, obviously. Why do you ask?

It's a little hard to answer these questions in the abstract. Why don't
you tell us more about why you are asking and what specifically your
circumstances are? That will increase the chance that we can help you.

>I heard that stream ciphers are better when it comes to real time
>processing(as there is no time for error correction). Any comments
>regarding this?

Sounds dubious to me. The performance issue with decrypting audio
in real time, if there is one, is likely to be bandwidth, not latency.
At least, that would be my expectation.