Re: on FPGAs vs ASICs

2005-03-21 Thread Riad S. Wahby
"Major Variola (ret)" <[EMAIL PROTECTED]> wrote:
> Riad doesn't seem to appreciate this.

Of course I do.  I'm saying that for our purposes (a dedicated
hashcracker) we want an ASIC.  Whether we can afford one or not is
another question (obviously if we can't, we buy the best FPGA we can).

...or are we no longer assuming an adversary with unlimited resources?

-- 
Riad S. Wahby
[EMAIL PROTECTED]



Re: on FPGAs vs ASICs

2005-03-21 Thread Tyler Durden
FPGAs probably make more sense for routers,
because you want the ability to change the firmware more often,
and a router has a bunch of other parts as well,
and realistically, cypher-cracking is not an
economically viable activity for most people,
so the cost-benefit tradeoffs are a bit twisted.
The router world seems to use a good mixture. At a startup we were 
purchasing nice off-the-shelf MPLS ASICs, which did MPLS route setup and 
forwarding (and some enforcement) while the 'software'/control plane (eg, 
OSPF, RSVP-TE, etc...) was largely in FPGAs of our own brew.

At that time (ca, 2000/2001) some vendors were starting to push net 
processors, which were somewhere in between, and at the time just weren't 
quite fast enough for ASIC-busting applications and not quite flexible 
enough for FPGA-ish applications. Now, however, I'd bet net processors are 
very effective for metro-edge applications.

What I suspect is that there's already some crypto net processors out there, 
though they may be classified, or the commercial equivalent (ie, I assume 
there are 'classified' catalogs from companies like General Dynamics that 
normal clients never see). They can periodically upgrade the code when they 
discover that some new form of stego (for instance) has become in-vogue at 
Al Qaeda.

These won't be Variola Suitcase-type applications, though, but perhaps for 
special situations where they know the few locations in Cobble Hill Brooklyn 
they want to monitor and decrypt.

-TD



Re: on FPGAs vs ASICs

2005-03-21 Thread Bill Stewart
At 11:11 AM 3/19/2005, Major Variola (ret) wrote:
 ---useful if you can't afford an ASIC run (a million bucks a mask...)
...
For someone making 10,000 routers, you use FPGAs.
DESCrack was solving a problem for which the x86 is not very efficient
at computing --all the sub-byte bit-diddling--
and hardware is very efficient (by design in DES, after all).
EFF's DESCrack cost $200K in 1998 and used ASICs.
(It's really only six years since we killed off single-DES!)
There were 1500 DES-cracker ASIC chips in it.
ASICs may cost a bit more today - Moore's Law helps,
but it also means that chip designs can become
larger and more complex, though code-cracker applications
have a lot of uniformity in their design,
and we've got six more years of experience
building ASIC cell libraries that can be reused.
I suspect a similar-sized machine would cost a similar amount
but have a lot more DES functional units in it.
FPGAs probably make more sense for routers,
because you want the ability to change the firmware more often,
and a router has a bunch of other parts as well,
and realistically, cypher-cracking is not an
economically viable activity for most people,
so the cost-benefit tradeoffs are a bit twisted.