On Thu, Oct 25, 2007 at 08:37:02PM +1300, Richard Toohey wrote:

quoted text
> On 25/10/2007, at 8:28 PM, Richard Toohey wrote:

>

> >You are in charge of getting four ambassadors to a meeting.  As

> >well as making sure they are happy and fed, you are in charge of

> >their security.

> >

> >All four are hated in their home countries and you know their are

> >people wanting to kill them.

> >

> >Some of your choices:

> >

> >1. One car per ambassador.  If one gets taken out, at least three

> >are still OK (guess you would still be out of a job, though - so

> >not a perfect analogy.)  Obviously means four cars, four drivers,

> >so more expensive.  And more things to juggle.  And if you are very

> >unlucky, all four could still get taken out (but obviously means a

> >lot of bad guys being lucky.)  It takes four attacks to wipe you out.

> >

> >2. All four in one car.  If any assassin tries to take out an

> >ambassador, chances are the rest are toast as well.  But only one

> >car / one driver - so less expensive.  It takes one attack to wipe

> >you out.

> >

> >3. All four in one car - but you start to worry about the risk, so

> >you start adding stuff to the car.  Bigger engine, stronger body,

> >try and partition off the passengers, give them body armour, have a

> >spare driver, get the driver to drive randomly - lot more

> >complexity and things to juggle.  Unless you and the car builder

> >are very good (did you think of EVERYTHING?  What exactly did the

> >car builder DO under the bonnet - do you know?) - one attack will

> >still wipe you out.

> >

> >Which of these options is "most secure"?  (Sending them with Arnie

> >in his Hummer isn't an option.)

> >

>

> And - just to extend the analogy further - the risks may not be

> malicious.  So if any of the above scenarios the risks would also be

> accidental - car crashes, driver has heart attack, plane falls from

> sky, etc.  Something outside your control.  Obviously for number 1 -

> one accident does not wipe you out.

>

> And one other extension - number 3 - the beefed up car - perhaps one

> of the modifications goes wrong (so again, not a malicious attack) -

> the engine overheats because of the extra weight, catches fire, and

> your other mods mean that they're all locked in.  The glue from the

> partitions is toxic and they are overcome by fumes.  Whatever.  One

> accident wipes you out completely.

Problem:  in your analogy, there is some limit to the number of bad guys

before they become obvious to local law-enforcement.  In the computer

case, best to consider the number of bad guys unlimited; you can only

limit the _rate_ at which they try to attack via the net (physical

security is back to the car analogy; how many datacentres do you need).
Answer to your question:
4 cars, all dummies.
Dress the diplomats up as cleaning staff and send them via public

transit.
This is where the analogy breaks down.  The safety of the ambasidors

relies on secrecy; if its blown, the bad guys will know which car the

good guys are in and will blow it up.  If it secrecy remains tight, they

won't know your plans whatever they are.  
Doug.