What is QKD(Quantum Key Distribution)?

Question

What is the advantage over the earlier methods?

Answer 1

QKD is a method of encryption, also called quantum cryptography.

An important and unique property of quantum cryptography is the ability of the two communicating users to detect the presence of any third party trying to gain knowledge of the key. This results from a fundamental part of quantum mechanics: the process of measuring a quantum system in general disturbs the system. A third party trying to eavesdrop on the key must in some way measure it, thus introducing detectable anomalies. By using quantum superpositions or quantum entanglement and transmitting information in quantum states, a communication system can be implemented which detects eavesdropping. If the level of eavesdropping is below a certain threshold a key can be produced which is guaranteed as secure (i.e. the eavesdropper has no information about), otherwise no secure key is possible and communication is aborted.
This is a method of encryption.

The security of quantum cryptography relies on the foundations of quantum mechanics, in contrast to traditional public key cryptography which relies on the computational difficulty of certain mathematical functions, and cannot provide any indication of eavesdropping or guarantee of key security.

Answer 2

you may freely distribute your public key, and nevertheless be waiting to establish a secure verbal replace channel. in comparison to symmetric encryption, which suffers from key distribution issues (you may not securely communicate till the two facets have a mutual secret key, yet you may not provide the different section a secret key because of the fact you do not have a secure verbal replace channel), public-key encryption has a public-key used to encrypt the message, and a private key used to decrypt the message. consequently, you may freely publicize the everyday public key, and anybody can use it to encrypt the message. as quickly as the message is encrypted, even the guy who encrypted it can not decrypt it. basically you, with the interior maximum key, can decrypt the message. at the instant, the main nicely-usual public-key encryption approach is RSA, this is set by potential of modular arithmetic and the reality that it somewhat is concept to be very complicated to ingredient numbers into their top factors.

Answer 3

Snake Oil. It doesn't really work. There is still no way to spot a man-in-the-middle attack (remember, the MITM will guess correctly as often as you can; the MITM doesn't have to transmit the same thing as your partner transmitted, because you are going to have to try to guess it anyway, and you are no less likely to guess the MITM's bits correctly than your partner's bits), and it *still* requires a separate, secure channel to verify the key.

The only advantage it has over earlier methods is that it sounds more scientific, and so scientifically-illiterate but easily-impressed venture capitalists are more likely to hand over vast sums of money for your pointless but lucrative research.

Answer 4

primarily the advances allow greater privacy and notices "observers"/eavesdroppers and such. Check out the source below: quite comprehensive.

Answer 5

better google