-The very important precaution is the @strong{cryptographically good}
-pseudo random number generator. GoVPN uses native operating system PRNG
-as entropy source. You have no way to check its quality in closed
-source code operating systems, so it is recommended not to use them if
-you really needs security. Moreover it is possible that those OS leaks
-information about possible PRNG states. And at least Apple OS X and
-Microsoft Windows are already known to have weak CSPRNGs.
-
-GoVPN could use its own PRNG implementation like
-@url{https://www.schneier.com/fortuna.html, Fortuna}, but it is
-much easier to use the right OS, to use free software.
-
-Also you should @strong{never} use one key for multiple clients. Salsa20
-encryption is randomized in each session, but it depends again on PRNG.
-If it fails, produces equal values at least once, then all you traffic
-related to that key could be decrypted.
-