David McClain wrote: ... On Jan 31, 2010, at 03:02 AM, David McClain wrote:
Okay, not fair... that troika took me about 18 months from start to =
finish.That works out to around 6 man-months each, figure 30-40 KLOC in =
each module of the three. We don't have that kind of time for a simple =
challenge... So try this one instead: SRP-6 Secure Remote Password protocol
for = authenticated login between client and server. You will need to be
able= to generate a 1024-bit prime number of the form P =3D 2*N+1, find a =
decent sized primitive root to get good bit mixing in the exponentiation =
routines, provide two socket connections that initiate this protocol off =
the bat, and provide the SHA256, MD5, and AES-128 for the protocol.=20 =20
Attached PNG (if it makes it through, otherwise I'll post the exchange =
protocol on my web site). That page describes the interchange between =
client and server. As a shared pass phrase lets use "Forth / Lisp =
Challenge". This ought to take a few days at most, if you have to = develop
the encryption routines. Otherwise, it should take no more than = an hour or
so. We implemented triple-DES, MD5, and RSA with 1024-bit keys in a
smart-card terminal project[1] we did for Europay International (now
EuropeanMasterCard), in the late 90's. I probably still have the code
around, but unfortunately it's wildly proprietary for obvious reasons! We
did write it completely from scratch, and ran it on a range of machines
including 8051, 68xxx, embedded 80x86, and PCs under Windows. As I recall,
the encryption algorithms did take a few days each, plus a day or so to
optimize for the various processors. Performance was sufficiently good that
even on the 8051s performance was dominated by I/O time. I confess, I
didn'twrite this personally!
As luck would have it, just last night I got an email from an old customer
who has been using a system I developed along with Chuck Moore in the late
70's. It does some extremely complex analysis to compute the overlapping
bonded indebtedness for municipal bonds in California, involving a
substantial database implemented entirely in Forth. It has been ported to
various architectures over the years, and is currently running on PCs. They
wrote to inquire about porting it to MacOS (Joel Reymont is involved with
this). I understand that the State of California undertook to re-write this
system (for mainframes) for themselves a few years ago, and after spending
several $M abandoned the project. Chuck and I wrote it in about six weeks.

My last example is another project I managed some years ago, involving
control of online functions at an airport. It involved a network of about
400 computers controlling over 36,000 points (digital, analog, etc.) over
several hundred square miles, via a large database. My team (about 5
programmers, supplemented by 10 trainees from our client) was brought in as
a"rescue mission" after a crew of about 35 programmers had worked on it for
over three years, producing code that was very incomplete functionally and
fell far short of contractual performance specs. Starting from scratch, we
produced (all in Forth) a system that met the functional specs and exceeded
the performance requirement (a factor of 10 faster than the discarded
system,on the same hardware), in under 18 months. There is an article about
this floating about the internet somewhere.

Unfortunately, I do not have the time to respond by writing code myself (and
much of the code we have is proprietary), but hope that citing these very
different projects, which share the aspects of significant logical
complexity, and excellent performance, and very fast development times, will
address your points.

Cheers,
Elizabeth
-- ================================================== Elizabeth D. Rather
(US&Canada) 800-55-FORTH FORTH Inc. +1 310.999.6784 5959 West Century Blvd.
Suite 700 Los Angeles, CA 90045 http://www.forth.com[2] "Forth-based
productsand Services for real-time applications since 1973."
==================================================

--- Links ---
   1 http://www.forth.com/downloads/OTA_FD.pdf
   2 http://www.forth.com
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Received on Sun Jan 31 2010 - 15:02:37 PST