Which mechanism does OAuth use to strengthen REST API security when compared to BasicAuth?

OAuth employs tokens (e.g., access tokens) as a credential mechanism, allowing client applications to access resources on behalf of a user without the user's actual username and password being directly shared with or stored by the client, significantly reducing credential exposure compared to BasicAuth.

SSL (Secure Sockets Layer) is a deprecated cryptographic protocol for securing communication; it is a transport-layer security mechanism, not an authentication mechanism specific to OAuth's design advantage over BasicAuth.

Authentication is the general process of verifying identity, which both OAuth and BasicAuth perform; it is not the specific mechanism OAuth uses to strengthen security in comparison.

TLS (Transport Layer Security) is a cryptographic protocol used to secure communication over a network; while essential for securing token exchange, it is a transport-layer security protocol, not the core token-based authentication mechanism that differentiates OAuth from BasicAuth.