"Vin McLellan" <[EMAIL PROTECTED]> writes:
> The Wheelers' comments -- a response to my claim that RSA's fabled
> crypto savvy influenced the design of the SecurID OTP token -- were
> inaccurate and misleading.
>
> I've been using the Wheeler's posts to educate and frighten my clients
> for years, so I'm sure the error is unintentional, perhaps even caused
> by some lack of clarity in my earlier post. Since the Wheelers'
> industrial history archive is likely to be referred to often in the
> years to come, however, I did not want even this brief aside to stand
> uncorrected.
>
> It should surprise no one, certainly not Lynn Wheeler, that after the
> 1996 merger of SDI and RSADSI, RSA's new team of cryptographers and
> crypto engineers began to urge a completely redesign of the original
> SecurID system around stronger (128-bit) cryptosystems.
>
> (The RSADSI folks were not unfamiliar with the SecurID.  The SecurID
> client/server protocol had been designed around a proprietary hash
> developed for SDI by Ron Rivest, the "R" of RSA.  After the merger,
> RSA's crypto engineers pushed to harden the SecurID system -- which
> already had a huge installed base, and dominated its market niche --
> against new threats from the ubiquitous network and the Web. I was then
> a consultant to SDI, as I am now to RSA -- a bit of the proverbial fly
> on the wall.

this is along the lines of the old silicon valley joke about there
actually only being 200 people in the industry ... it looked like
more, because the same people just kept moving around.

i was mainly referring to RSA public key cryptography ... which most
people identify RSA with ... differentiated from non-RSA public key
infrastructure used by SecureID.

in that time-frame, there were also a lot of stuff going on around RSA
public key cryptography and the use of RSA digital signature in
hardware tokens for authentication ... types of stuff you find in SSL,
the various PKCS standards ... including work on PKCS#11 that RSA,
Netscape, etc was pushing for RSA (public key digital signature)
authentication smartcards ...  as opposed to secureid cards (there
were some PKCS#11 meetings with the various participants at the toll
house in los gatos).

also, much of the differential power analysis is heavily oriented
towards RSA public key smartcards (attacks on rsa private key)

one of the issues in heavy push for RSA public key digital signatures
for smartcard authentication ... was that the alternative was FIPS186
digital signature which required a reliably random number be generated
as part of the digital signature calculation. most of the hardware
token chips from the period not only had issues with differential
power analysis (attacker being able to obtain lots of information
about RSA private key during RSA digital signature and/or encryption
operation) but had dismal random number capability. One extensive
study of most chips from the period ... involving power-off/power-on
generate random number ... repeated 65k times, found nearly all chips
having something like 30 percent of the time, there was a repeated
random number.

i've frequently contended one of the reasonse there was extensive
standards work on RSA digital signature authentication during the
period ... was because the alternative gov. standard FIPS-186 digital
signature (for strong authentication) was heavily dependent on random
number generation during the digital signature calculation process
... that made it nearly useless in hardware tokens of the period (aka
poor random number generation could reveal more about FIPS-186 private
key than differential power analysis was revealing about RSA private
key).

However, for that generation of RSA public key tokens, the common
practice was to pre-personalize the tokens by using an external box
... with a reliable random number generation source ... to generate
the RSA public/private key pair and inject the RSA private key into
the token (since reliable random number generator is also required
during the key generation process).

In the late 90s, you started to see a combination of things ...
FIPS186-2 was upgraded to included ECDSA ... which has radically
different private key vulnerability to differential power analysis,
(especially compared to RSA), chips that had acceptable hardware
random number characteristics (eliminating private key exposure
vulnerability because of poor random number generation), and
sophisticated power use management that included injected random power
cycles(as additional countermeausre to differential power analysis).

I joke during the period that i could take a $500 milspec part, cost
reduce it by two orders of magnitude and at the same time, make it
more secure. Some of the smartcard endevors got into this vicious
negative feedback loop, the cards were more expensive than a single
purpose could justify, so add more features, which increased the cost,
which required adding more features to justify the cost, which
increased the cost. an alternative approach was to aggresively cost
reduce all the components ... throwing out everything not required for
authentication. part of the issue around extraneous features is that
they can contribute to insecurity.

the advent of chips with higher quality random number generation also
it made it feasable to start during key generation on the chip
(eliminating the pre-personalizing step where keys are generated by
external boxes and injected into the chip).

however, there is frequently still a strong tendency to get into the
negative feedback cycle of increasing the features to justify the
cost, which increases the cost (and complexity) , which requires even
more features to justify the cost.

one of the downside of this other approach to authentication hardware
tokens is that they require an explicit hardware interface between the
environment and the hardware token. securid had a lower per seat entry
since existing keyboard and screen could be utilized. that may be in
the process of changing with the advent of wireless technologies that
can be used for a variety of different purposes ... including wireless
authentication token.

the upside of the digital signature tokens is that they require a much
simpler backend infrastructure operation (once the downside of the
interfacing has been overcome). it is possible to take the single/same
token and register the token's public key in a large variety of
different domains and environments ... resulting in a single token
authenticator ... this is the person-centric approach to
authentication contrasted with the institutional-centric approach that
effectively requires a unique token for every different security
domain. I once went around to most of the booths at a smartcard
conference ... joking that if the current (institutional centric)
hardware token paradigm ever took off ... people would be replacing
having to keep track of hundreds of passwords with having to keep
track of hundreds of hardware tokens.

random past posts mentiong the person/institution centric
authentication subject
http://www.garlic.com/~lynn/aadsm12.htm#0 maximize best case, worst case, or
average case? (TCPA)
http://www.garlic.com/~lynn/aadsm19.htm#14 To live in interesting times - open
Identity systems
http://www.garlic.com/~lynn/aadsm19.htm#41 massive data theft at MasterCard
processor
http://www.garlic.com/~lynn/aadsm19.htm#47 the limits of crypto and
authentication
http://www.garlic.com/~lynn/aadsm20.htm#41 Another entry in the internet
security hall of shame
http://www.garlic.com/~lynn/2003e.html#22 MP cost effectiveness
http://www.garlic.com/~lynn/2003e.html#31 MP cost effectiveness
http://www.garlic.com/~lynn/2004e.html#8 were dumb terminals actually so
dumb???
http://www.garlic.com/~lynn/2005g.html#47 Maximum RAM and ROM for smartcards
http://www.garlic.com/~lynn/2005g.html#57 Security via hardware?
http://www.garlic.com/~lynn/2005m.html#37 public key authentication
http://www.garlic.com/~lynn/2005p.html#6 Innovative password security
http://www.garlic.com/~lynn/2005p.html#25 Hi-tech no panacea for ID theft woes
http://www.garlic.com/~lynn/2005t.html#28 RSA SecurID product

--
Anne & Lynn Wheeler | http://www.garlic.com/~lynn/

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