Although I like the idea of shorter key-sizes, there are some points you should consider when using ECC (DUAL_EC_PRNG).

Check out Bruce Schneier's blog regarding this topic: https://www.schneier.com/blog/archives/2015/10/why_is_the_ns...

Ack. However from the paper Schneier links to:

> The Dual EC DRBG is atypical, in that no other standardized ECC protocol has any known way to insert a back door.

https://eprint.iacr.org/2015/1018.pdf