Which technology is primarily used to secure communication between the frontend and backend?

The primary technology used to secure communication between the frontend and backend is Transport Layer Security (TLS). TLS is a cryptographic protocol that ensures privacy and data integrity between two communicating applications, such as a web browser and a server. It provides essential security features, including encryption, which protects the data being transmitted from eavesdropping and tampering. This is crucial for maintaining the confidentiality and integrity of sensitive information, such as login credentials, payment details, and personal data when users interact with web applications.

While Secure Sockets Layer (SSL) is the predecessor to TLS and provides similar functions, it is considered outdated and has known vulnerabilities. Thus, TLS has largely replaced SSL in modern applications. HTTP Basic Authentication and OAuth 2.0 are mechanisms for user authentication and authorization, but they do not secure the communication channel itself; instead, they work within the context of established secure connections like those provided by TLS. Therefore, TLS stands out as the correct choice for securing data in transit between the frontend and backend systems.