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  • Chris Kang thinks this is interesting:

Nonetheless, sometimes you might find a protocol that does what you need, but can’t find an implementation that suits your needs. Alternatively, you might find that you do need to come up with your own protocol. For those cases, we do document the SSL cryptographic API.

From

Cover of Network Security with OpenSSL

Note

Using available SSL API you can apply your own protocol (ie. how an algorithm is applied to get the necessary security). eg. How key is exchanged and how such information is cahed etc.