http://curvezmq.org/page:read-the-docs

https://blog.cloudflare.com/a-relatively-easy-to-understand-primer-on-elliptic-curve-cryptography/

https://en.wikipedia.org/wiki/Curve25519

Sodium is a packaging of the NaCl crypto library, which implements the Curve25519 elliptic curve cryptography (ECC) algorithm. It doesn’t matter for this tutorial, but when you use ECC in real work, people will ask you (a) isn’t ECC backdoored by the NSA?, and (b) how secure is this, and (c) how fast is it, and (d) who else uses it?

The answers are, at least today, (a) some ECC curves may be, and older crypto like RSA probably is, but Curve25519 is not, (b) it provides 256 bit ECC keys which is as strong as 3072 RSA keys, and (c) it’s one of the fastest elliptic curves out there. Also, (d) it’s not exactly mainstream, but is gaining popularity and Google is using it for their Quik protocol.

https://github.com/zeromq/pyzmq/tree/master/examples/security