Bullet-proofing your online data

ROMA – Dr Makhamisa Senekane, a lecturer in the Department of Physics and Electronics at the National University of Lesotho (NUL) is assessing a new way of bullet-proofing your online information to ensure it is safe.
When you send sensitive information online, such as banking information, there is a way to hide that information from crooks.
“However,” he says, “some methods of hiding information (encryption) are very difficult to bullet-proof. That is why we are assessing a new way of bullet-proofing the security of your online experience.”

In the world of information hiding (encryption), you are sending the information from this side and your name is Alice.
And the one who receives the information on the other side is called Bob (Robert).

As far as Alice and Bob are concerned, one can sleep peacefully at night, these folks cause no problems whatsoever.
But then comes the third person called Eve (Eavesdropper, if you know what we mean?) and everything turns upside-down.

Eve is interested in getting the message that Alice is sending to Bob, so that she (Eve) can use this message for her personal gain.
That message may as well be a password you use to log into your online banking system.

If Eve is successful, you may wake up one day with all your money wiped off from your bank account in one stroke.
Now you know why the gurus, like Dr Senekane, are working day and night to make sure that that just won’t happen, if possible.
First, let’s consider one of the normal approaches which Senekane says it’s hard to prove their security.
Rest assured, we are using the simplest examples, in real life, it is more complex.

Suppose Alice is sending a number 10 to Bob on the other side of the online device.
But both know that Eve, that shady character, is waiting like a hungry shark on the route between them, to devour the information.
Hiding now begins.
The computer system generates the information called security keys.
Let’s say it gives the first key to Alice as the number 3 and the second key to Bob as the number 7.
“Prime numbers, those numbers such as 2, 3, 7, 11, 13, 17, the numbers that can only be divided by 1 or themselves, are often preferred because, as they get bigger, they are often hard to deal with,” Senekane says.
A bit of maths here but a simple one will suffice.
On the side of Alice, 10 is raised to power 3 times 7 (Remember 3 for Alice and 7 for Bob).
So 3 times 7 is 21.

So 10 is raised to power 21 which makes the number 1000000000000000000000, that is, 1 followed by 21 zeros.
When Eve the crook tries to steal the information, she comes across this ginormous number.
She is fooled because she doesn’t know that actually, that number represents 10.

When this mammoth number reaches Bob’s side of the system, Bob’s side has two advantages.
It “knows” Bob’s own key, 7, and it “knows” Alice’s key, 3.

Immediately, it can tell that there was a number which was raised to power 3 times 7—a number that was raised to power 21.
To arrive to this mammoth number (1 with 21 zeros), it can only mean that 10 was raised to power 21.
Now it is clear, Alice sent Bob the number 10!

But it appeared to Eve as a huge number she could not make sense out of.
Problem solved?
Not so fast.
It is not difficult to see that should Eve have access to both Alice and Bob’s keys, that is 3 and 7 respectively, she doesn’t need to be a rocket scientist to realize the hidden number sent was actually 10.
“That is why we need to hide these keys also, 3 and 7 and that is the most difficult part,” Dr Senekane says.
“It is hard to prove mathematically, that Eve can’t find the keys and use them for her own benefit.”
That is why he is assessing the use of quantum physics.

In this case, another line is created between Alice and Bob to exchange keys.
But the keys are sent, not as numbers but as photons (very tiny particles that make up light).
The number of particles interpreted in the binary format, are translated to either 3 or 7 for Alice and Bob.
But here is the big trick for Eve.

Photons are quantum particles (that is enough).
When you try to measure them they become something else.

So when Eve tries to measure these particles, they lose their identity (from quantum to classical) and the Bob’s side immediately realises that Eve interfered and the whole transaction stops.
What matters, is not so much that Eve did not see the information.

It is that we can detect that she saw the information and we can stop her on her tracks.
So Dr Senekane and the team are working to ensure that the techniques used to generate these keys using quantum physics are indeed mathematically provably secure.
This is to ensure that if the techniques are implemented correctly, the only way that Eve can interfere without being detected is by violating the fundamental laws of nature; a feat that is quite impossible.

Own Correspondent