In the case of TLS, at least, there is a set of mandatory to implement algorithms, so in principle two conformant implementations should be able to interoperate

In the case of TLS, at least, there is a set of mandatory to implement algorithms, so in principle two conformant implementations should be able to interoperate using those. Currently, they are: - ECDSA with P-256 for signature - ECDH with P-256 for key establishment - AES_128_GCM for data encryption with SHA-256 for hashing and KDF