How is IFF working?

[Tobias Endrullis]

Hi,
can anyone tell (explain) me how IFF mode 4 is working? Or does anyone know a page in the web where I can find information about
that?

Tobias

[GLOSM]

Americans need not answer

[Tobias Endrullis]

"GLOSM" > schrieb im Newsbeitrag ...
> Americans need not answer

yep, but I would like to know!!!!

[Brian]

"Tobias Endrullis" > wrote in message
...
>
> "GLOSM" > schrieb im Newsbeitrag
...
> > Americans need not answer
>
> yep, but I would like to know!!!!

It uses a ROT-13 encoded flux capacitor to generate very high powered
microwave pulses that can only be decoded with another matched flux
capacitor. Use the wrong flux capacitor and you get nothing.

[Gene Storey]

There really isn't much data published on the IFF algorithm,
because it is mostly confidential, and not released to the public.

Basically the system is a challenge/response system. You challenge
the target with an encrypted word. This word is decoded if you have
the right code of the day. The word is changed every challenge, so
in effect, you may get a stream of 100 words, and you have to
decode about 95% of them in your 100 replies, or you will not be
upgraded to friend.

The word tells you to do something with the reply pulses.

Since IFF is in the L-Band, it is pretty much line-of-sight, and most
operators will select a single target on their scope, and the IFF will
operate over just that azimuth.

German IFF (NATO) is the same as all other IFF systems in the west.
The newer Soviet IFF system operates pretty much the same as NATO
and is also L-Band.

"Tobias Endrullis" > wrote
> Hi,
> can anyone tell (explain) me how IFF mode 4 is working? Or does
> anyone know a page in the web where I can find information about
> that?

[Larry]

Ah yes Comradski. You vont to know this Information Friend or Foe, more
commonly known as IFF, yes?

Dis system relies on a "daily key" or "Code of the day" and if I told you
more, I'd have to . .


Larry
AECS (AW/SW/MTS)
Disabled Combat Veteran
USN Retired

20 years of Navy in my rear view mirror
and getting further away every day ;-)



"Tobias Endrullis" > wrote in message
...
> Hi,
> can anyone tell (explain) me how IFF mode 4 is working? Or does anyone
know a page in the web where I can find information about
> that?
>
> Tobias
>

[Abe]

In article <4xzvb.153$US3.85@okepread03>, says...
> Basically the system is a challenge/response system. You challenge
> the target with an encrypted word. This word is decoded if you have
> the right code of the day. The word is changed every challenge, so
> in effect, you may get a stream of 100 words, and you have to
> decode about 95% of them in your 100 replies, or you will not be
> upgraded to friend.

What if a plane was captured, along with its IFF system? Wouldn't that
invalidate the IFFs in every other friendly aircraft?

[Gene Storey]

"Abe" > wrote
> In article <4xzvb.153$US3.85@okepread03>, says...
> > Basically the system is a challenge/response system. You challenge
> > the target with an encrypted word. This word is decoded if you have
> > the right code of the day. The word is changed every challenge, so
> > in effect, you may get a stream of 100 words, and you have to
> > decode about 95% of them in your 100 replies, or you will not be
> > upgraded to friend.
>
> What if a plane was captured, along with its IFF system? Wouldn't that
> invalidate the IFFs in every other friendly aircraft?

Without the crypto code, the hardware is of no use. There's all sorts of
safeguards (procedural and electro/mechanical) to coding the unit.

But even if captured intact, the code could be changed before the
scheduled time. The whole air defense system isn't centered on IFF,
it's just a tool. If none of the IFF's were used, the defense system
could still function with procedural agreements. Stealth fighters almost
never use IFF, but are able to integrate into the air defense system.

[Alan Minyard]

On Sat, 29 Nov 2003 12:15:56 -0000, Abe > wrote:

>In article <4xzvb.153$US3.85@okepread03>, says...
>> Basically the system is a challenge/response system. You challenge
>> the target with an encrypted word. This word is decoded if you have
>> the right code of the day. The word is changed every challenge, so
>> in effect, you may get a stream of 100 words, and you have to
>> decode about 95% of them in your 100 replies, or you will not be
>> upgraded to friend.
>
>What if a plane was captured, along with its IFF system? Wouldn't that
>invalidate the IFFs in every other friendly aircraft?

No, since the enemy would not have the daily codes.

Al Minyard