...Uses only modern cryptography, with formally verified implementations. Small and constant memory footprint. Doesn't perform any heap memory allocations. Small (~25 KB), with an equally small and readable code base. No external dependencies. Works out of the box. No lousy documentation to read. No configuration file. No post-configuration. Run a single-line command on the server, a similar one on the client and you're done. No firewall and routing rules to manually mess with. Doesn't leak between reconnects if the network doesn't change. ...