Re: [CryptoAPI-devel] Re: [Design] [PATCH] USAGI IPsec

[JuanJo Ciarlante]

On Thu, Oct 24, 2002 at 10:50:26AM -0400, Jean-Luc Cooke wrote:
> On Tue, Oct 22, 2002 at 08:02:00AM +0300, Jari Ruusu wrote:
> > kerneli.org/cryptoapi _is_ useless joke for many needs. Fortunately other
> > people are able to see the limitations/sillyness of kerneli.org/cryptoapi:
> > 
> > 1)  You are trying to replace link/insmod time overhead with runtime
> >     overhead + unnecessary bloat.
> > 2)  No direct link access to low level cipher functions or higher level
> >     functions.
> > 3)  No clean way to replace cipher code with processor type optimized
> >     assembler implementations.
> 
> Jari has a few points here.  But the "killer" functionalities are all there
> IMHO.  Low-level assembler implementations are over-rated, again IMHO.  The
> performance difference between C and ASM is at most 50%.  1ms vs 1.5 ms.
> Even if you've got a large payload on the rare occation (>5MB) block ciphers
> are quite fast for 95% of applications

According to my tests, AES ASM has given me _2x_ speed boost over C; this
fact has re-written freeswan CPU/bandwidth empirical formula to peak at
       CPU [MHz] ~= BW [Mbit/s] * 10      (instead of 25)

This boost has allowed my old Cyrix-6x86 120MHz to be my 802.11b gateway  =)

--Juanjo       freeswan algo: AES (+others), SHA2, MODP2048-4096 
               selectable algorithms support for Phase1 and 2.
	       http://www.irrigacion.gov.ar/juanjo/ipsec/

#  Juan Jose Ciarlante (JuanJo PGP) jjo ;at; mendoza.gov.ar              #
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