Using a popular Blockchain seems to me to be the best C&C system. It's distributed and authenticated. The botnet could either talk directly to the network or fa

Using a popular Blockchain seems to me to be the best C&C system. It's distributed and authenticated. The botnet could either talk directly to the network or fallback to http and look at the hundreds of websites that allow you to read the blockchain. It would be "impossible" for the C&C to be taken over without the collaboration of the Blockchain developers and miners... It means "spending" to send a command, but you only lose the fee.