Which of the following are valid NFSv4 security types?

RSA is an asymmetric encryption algorithm, not a named NFSv4 security type (like `sec=`) itself, although it's used within other security protocols.

SSL (Secure Sockets Layer) is a protocol for securing network communications, but NFSv4 uses its own RPCSEC_GSS-based security mechanisms like Kerberos rather than directly implementing SSL as a security type.

SPKM (Simple Public Key Mechanism) is a security flavor supported by NFSv4 through RPCSEC_GSS, providing integrity and privacy services.

Kerberos is a widely used network authentication protocol and is a primary security mechanism for NFSv4, offering strong authentication, integrity, and privacy (krb5, krb5i, krb5p).

LIPKEY (Lightweight Internet Protocol KEYing) is another security mechanism supported by NFSv4 via RPCSEC_GSS, primarily for authentication and integrity.