Stryker/C-130 Pics

On 23 Sep 2003 20:00:32 -0700, Kevin Brooks wrote:

No. Paul is correct, DF'ing a "frequency agile" (or "hopping")
transmitter is no easy task. For example, the standard US SINCGARS
radio changes frequencies about one hundred times per *second*,

Bear in mind that I'm talking about automated electronic gear here,
not manual intervention. Electronics works in time spans a lot
quicker than 10 ms.

So what? Unless you know the frequency hopping plan ahead of time
(something that is rather closely guarded), you can't capture enough
of the transmission to do you any good--they use a rather broad
spectrum.

OK, I now understand that DF generally relies on knowing the
frequency in advance.

BTW, when you say a rather broad spectrum, how broad? And divided
into how many bands, roughly?

Both radios have to be loaded with the same frequency hopping (FH)
plan, and then they have to be synchronized by time. When SINGCARS
first came out the time synch had to be done by having the net control
station (NCS) perform periodic radio checks (each time your radio
"talked" to the NCS, it resynchronized to the NCS time hack); failure
to do this could result in the net "splitting", with some of your
radios on one hack, and the rest on another, meaning the two could not
talk to each other. I believe that the newer versions (known as
SINCGARS EPLRS, for enhanced precision location system) may use GPS
time data, ensuring that everyone is always on the same time scale.

That would make sense.

If two receivers, placed say 10 m aparet, both pick up a signal, how
accurately can the time difference between the repetion of both
signals be calculated? Light moves 30 cm in 1 ns, so if time
differences can be calculated to an accuracy of 0.1 ns, then
direction could be resolved to an accuracy of 3 cm/10 m ~= 3 mrad.

The fact is that the direction finding (DF'ing) of frequency agile
commo equipment is extremely difficult for the best of the world's
intel folks, and darned near impossible for the rest (which is most of
the rest of the world); that is why US radio procedures are a bit more
relaxed than they used to be before the advent of FH, back when we
tried to keep our transmissions to no more than five seconds at a time
with lots of "breaks" in long messages to make DF'ing more difficult.

So transmissions of 5 seconds tend to be hard to DF? Of course, with
the battlefield internet, a text transmission will typically be a
lot less than 5 s (assuming the same bandwidth as for a voice
transmission, i.e. somewhere in the region of 20-60 kbit/s).

transmissions still very clear), and the use of FH combined with
crypto key makes it darned near impossible for the bad guy to decypher
it in any realistic timely manner.

Modern crypto is good enough to withstand all cryptanalytic
attacks.

--
"It's easier to find people online who openly support the KKK than
people who openly support the RIAA" -- comment on Wikipedia

"phil hunt" wrote in message
. ..

transmissions still very clear), and the use of FH combined with
crypto key makes it darned near impossible for the bad guy to decypher
it in any realistic timely manner.

Modern crypto is good enough to withstand all cryptanalytic
attacks.

Thank you Admiral Doenitz...

L'acrobat wrote:

"phil hunt" wrote in message
. ..

transmissions still very clear), and the use of FH combined with
crypto key makes it darned near impossible for the bad guy to decypher
it in any realistic timely manner.

Modern crypto is good enough to withstand all cryptanalytic
attacks.

Thank you Admiral Doenitz...
------------
He's right. Major breaththrough of all possible barriers, the RSA
algorithm. Uncrackable in the lifetime of the serious user, and
crack is entirely predictable with improved computing power and
can be lengthened to compensate.

-Steve
--
-Steve Walz ftp://ftp.armory.com/pub/user/rstevew
Electronics Site!! 1000's of Files and Dirs!! With Schematics Galore!!
http://www.armory.com/~rstevew or http://www.armory.com/~rstevew/Public

"R. Steve Walz" wrote in message
...
L'acrobat wrote:

"phil hunt" wrote in message
. ..

transmissions still very clear), and the use of FH combined with
crypto key makes it darned near impossible for the bad guy to
decypher
it in any realistic timely manner.

Modern crypto is good enough to withstand all cryptanalytic
attacks.

Thank you Admiral Doenitz...
------------
He's right. Major breaththrough of all possible barriers, the RSA
algorithm. Uncrackable in the lifetime of the serious user, and
crack is entirely predictable with improved computing power and
can be lengthened to compensate.

The fact that you and I think it is unbeatable, doesn't mean it is.

"lifetime of the serious user" what ********, you and I have absolutely no
idea what sort of tech/processing power will be available 10 years from now,
let alone 30.

"and crack is entirely predictable with improved computing power" of course
it is...

Ask the good Admiral how confident he was that his system was secure.

Damn near as confident as you are and that worked out so well, didn't it?

On Thu, 25 Sep 2003 14:47:07 +1000, L'acrobat wrote:

"lifetime of the serious user" what ********, you and I have absolutely no
idea what sort of tech/processing power will be available 10 years from now,

Ever heard of Moore's law?

I've got a pretty good idea. A typical PC now has a 2 GHz CPU, and
about 256 MB RAM.

Assume these double every 18 months. 10 years is about 7 doublings
so in 2003 we'll see PCs with 250 GHz CPUs and 32 GB of RAM.


--
"It's easier to find people online who openly support the KKK than
people who openly support the RIAA" -- comment on Wikipedia

"phil hunt" wrote in message
. ..
On Thu, 25 Sep 2003 14:47:07 +1000, L'acrobat
wrote:

"lifetime of the serious user" what ********, you and I have absolutely
no
idea what sort of tech/processing power will be available 10 years from
now,

Ever heard of Moore's law?

I've got a pretty good idea. A typical PC now has a 2 GHz CPU, and
about 256 MB RAM.

Assume these double every 18 months. 10 years is about 7 doublings
so in 2003 we'll see PCs with 250 GHz CPUs and 32 GB of RAM.

Right. you are going to base national security matter on a rule of thumb
that relates to a typical PC.

Good move.

"L'acrobat" wrote

"phil hunt" wrote
L'acrobat wrote:

"lifetime of the serious user" what ********, you and I have
absolutely
no
idea what sort of tech/processing power will be available 10
years from
now,

Ever heard of Moore's law?

I've got a pretty good idea. A typical PC now has a 2 GHz CPU, and
about 256 MB RAM.

Assume these double every 18 months. 10 years is about 7 doublings
so in 2003 we'll see PCs with 250 GHz CPUs and 32 GB of RAM.

Right. you are going to base national security matter on a rule of
thumb
that relates to a typical PC.

Good move.

Historically, each and every crypto shop has been sublimely convinced
that_its_cypher was unbreakable. As near as I can tell, each and every
one of them was wrong. What makes that conviction so remarkable is
that most crypto shops either were breaking or had allies who had
broken the opposition's codes.

After the Walker Ring compromised US Naval codes and KGs for years, I
read an article in USNI Proceedings by a communications specialist who
airily waved that damage away with "we've changed all the keys". There
are more ways than brute force to break COMSEC.

L'acrobat wrote:

"R. Steve Walz" wrote in message
...
L'acrobat wrote:

"phil hunt" wrote in message
. ..

transmissions still very clear), and the use of FH combined with
crypto key makes it darned near impossible for the bad guy to
decypher
it in any realistic timely manner.

Modern crypto is good enough to withstand all cryptanalytic
attacks.

Thank you Admiral Doenitz...
------------
He's right. Major breaththrough of all possible barriers, the RSA
algorithm. Uncrackable in the lifetime of the serious user, and
crack is entirely predictable with improved computing power and
can be lengthened to compensate.

The fact that you and I think it is unbeatable, doesn't mean it is.

"lifetime of the serious user" what ********, you and I have absolutely no
idea what sort of tech/processing power will be available 10 years from now,
let alone 30.
-----------------
Nothing CAN magically guess extraordinarily long primes. That will
never just magically become possible. This intrinsic truth resides
in the very mathematics itself, a fact outside of time and progress,
and not in any technology of any kind.


"and crack is entirely predictable with improved computing power" of course
it is...

Ask the good Admiral how confident he was that his system was secure.
----------------------
Irrelevant. His system relied on technology, as any mathematician could
have told him. He merely held his nose and trusted the allies weren't
technically advanced enough to do it quick enough. He lost.

But the "bet" that RSA makes is totally different, in that it relies
statistically upon the ABSOLUTE RANDOM unlikelihood of any absolute
guessing of very large prime numbers by machines whose rate of guessing
is limited and well-known as their intrinsic limit. This number is a
VERY VERY VERY large prime number. In case you don't quite get it, the
most used high security prime number size is greater than the number
of atoms in the entire big-bang universe AND greater than even THAT
by an even GREATER multiplier! See the writings of James Bidzos, CEO of
RSA Tech. for these revelations.


Damn near as confident as you are and that worked out so well, didn't it?
------------------------
You have absolutely NO IDEA what the **** you're talking about.

-Steve
--
-Steve Walz ftp://ftp.armory.com/pub/user/rstevew
Electronics Site!! 1000's of Files and Dirs!! With Schematics Galore!!
http://www.armory.com/~rstevew or http://www.armory.com/~rstevew/Public

"R. Steve Walz" wrote in message


Nothing CAN magically guess extraordinarily long primes. That will
never just magically become possible. This intrinsic truth resides
in the very mathematics itself, a fact outside of time and progress,
and not in any technology of any kind.

That's true now, but only to a point. That point is the advent of quantum
computing, which allows you to effectively solve for all the possible
factors in very little time (say 10^500 times faster than conventional
computing for this sort of problem). If QC happens, large prime number
encryption is crackable in a matter of seconds. And there is at least some
reason to beleive that QC is achievable within a couple of decades.

OTOH, the real danger in the near- to mid-term is not crypto-system attack,
but physical compromise of the crypto-system (the adversary getting hold of
the both the mechanism and the keys themselves). If they have the actual
keys, the eavesdroppers can decode RSA just as easily as the intended
recipients.

--
Tom Schoene Replace "invalid" with "net" to e-mail
"If brave men and women never died, there would be nothing
special about bravery." -- Andy Rooney (attributed)

Thomas Schoene wrote:

"R. Steve Walz" wrote in message


Nothing CAN magically guess extraordinarily long primes. That will
never just magically become possible. This intrinsic truth resides
in the very mathematics itself, a fact outside of time and progress,
and not in any technology of any kind.

That's true now, but only to a point. That point is the advent of quantum
computing, which allows you to effectively solve for all the possible
factors in very little time (say 10^500 times faster than conventional
computing for this sort of problem). If QC happens, large prime number
encryption is crackable in a matter of seconds. And there is at least some
reason to beleive that QC is achievable within a couple of decades.
-----------------------
Or DNA computing, sure.

Just an escalation, the power of operations easier one way than the
other persists and an increase in length results in the same safety.

For it to be otherwise you need to postulate that the govt will be
doing its own fundamental research, and it NEVER does, and that it
will develop QC to that level BEFORE the market sells it or the people
developing it steal it and spread it around to prevent a national
monopoly on power, and that's pretty unlikely.


OTOH, the real danger in the near- to mid-term is not crypto-system attack,
but physical compromise of the crypto-system (the adversary getting hold of
the both the mechanism and the keys themselves). If they have the actual
keys, the eavesdroppers can decode RSA just as easily as the intended
recipients.

--
Tom Schoene Replace "invalid" with "net" to e-mail
"If brave men and women never died, there would be nothing
special about bravery." -- Andy Rooney (attributed)
---------------------
Yes. Goes without saying.

-Steve
--
-Steve Walz ftp://ftp.armory.com/pub/user/rstevew
Electronics Site!! 1000's of Files and Dirs!! With Schematics Galore!!
http://www.armory.com/~rstevew or http://www.armory.com/~rstevew/Public