basingwerk wrote:
That is not the point of my pointers! Java tries to prevent pointers from being reassigned in the way Roger described. It is not like C/C++. I’ve asked him to produce a case in Java – perhaps you know how to reassign a pointer to a corrupt stack? Let me know if you manage it - avoidance of it could go in the requirements for any system.
As I wrote previously, you are thinking at too high a level. Perhaps a Java compiler/interpreter tries to prevent this - but what do you thing the computer actually executes? (Flashback to The Matrix - do you think that's air you're breathing?) The pointer exists at a particular address and points to an executable block, complete with data, at another part of memory. All that is needed is to change the value stored at the first address - and you can do that outside Java. So, if pointers are used no language can completely prevent redirection.
Now for something that might shock you: Every language uses pointers because that's how computers work.
Code:
LDA FF EA 08 43
The above bit of pseudo assembler loads the accumulator with the address of the next piece of code to execute, or the start of a data block - seems like a pointer to me. If you're not already familiar with 6502, 8086, et al. Assembler, you might find 2GLs an eyeopener. If you don't mind the headaches, delving into 1GLs might worry you more.
So, all digital computers use pointers. Their system of registers make this inevitable. This means that your requirement cannot be met in todays systems and I can't see a way of meeting that requirement in any digital system.
basingwerk wrote:
Yes, but why do you talk of invincible computer-based systems? Do you know of invincible anything-based systems? Hm…
Now, on a practical level, is it easier to
1) Put a Guinness bottle label in the tax disc holder?
There is a huge difference. Putting a Guiness bottle lable in a tax disc holder invalidates a very small part of the system. In your brave new world, a successful attack could bring the entire system down. In extremis nobody would be allowed to travel because the road system would probably "fail safe" to the fiscal benefit of the Government - red-lighting anyone the system did not recognise until a human could "deal with" the miscreant (how else could you automatically police this). Enough "sheeple" would obey the red lights to prevent anyone from moving and people might die in the ensuing chaos.
basingwerk wrote:
As for the unknowns, they’ll come to light when they happen and be fixed, so all your comments lack relevancy in that respect.
We cannot afford that approach. How many people would you have die because the country ground to a halt as another of the "irrelevant unknowns" become known?
basingwerk wrote:
So, in the light of all that, do you doubt that new technology for will be used for establishing identity?
My fear is that it will be used and when (not if) the system fails, the "computer" rather than the truth will be believed. We've already seen some of your brave new world in the article reported
here, in the Times. The victim was hounded for over two years for 52 offences he did not commit, including one motoring offence that has cost him over £30,000 to defend. At one hearing, the prosecution claimed that the defendant had been excused because he was in prison for wounding - at which point he jumped to his feet and said: “No, I am not. I’m here.” At one hearing, he was threatened with being charged with contempt of court for trying to explain that it was a case of mistaken identity.
Further reliance on technology rather than common sense to establish identity can only cause more such harm.