What is really annoying about the quantum cryptography field is the dishonesty (in my opinion) that goes on with justifying the need. The need for QKD is often

What is really annoying about the quantum cryptography field is the dishonesty (in my opinion) that goes on with justifying the need. The need for QKD is often justified by quantum computers, shors algorithm and how cryptography will not be future proof once quantum computers will be around and that people can store all the data and already and decrypt sometime in the future. QKD is then brought in as the solution because channels are "physically secure" and often mention as alternatives to post quantum cryptography. Apart from the big question marks around quantum computers, the argument is dishonest. Post quantum algorithms are primarily about assymetric encryption, QKD is not a solution for the same problem at all. QKD is simply a way of ensuring that your optical channel is secure, so you can distribute onetime pads. The encryption is the onetime pad. And nobody is thinking about having QKD links between individual desktop PCs (that seems completely unfeasible atm). Essentially QKD is the same thing as sending a guard with a suitcase full of harddrives between your end points to distribute your keys (and in fact sending a guard is typically several orders of magnitude faster considering the current distances and data rates). In addition to the dishonest argument about the need there is the issue when they mentioning rates and distances. Often when talking about best key distribution rates proponents mention the MB/s that you can achieve with continuous variable QKD, but in the same argument they talk about the ultimate security achievable with discrete variable QKD. But data rates for discrete variable QKD are much lower, while the security of continuous variable QKD relies on statistics and more susceptible to attacks. So the arguments make QKD much better then the reality.