What is the primary security mechanism used to protect SOAP and REST APIs?

While general network firewalls offer perimeter protection, they do not specifically secure the API communication payload itself or encrypt the data in transit.

XML firewalls are specialized for XML-based SOAP APIs but are not universally applicable to all REST APIs (which often use JSON) and do not provide the foundational transport-level encryption.

Encryption, primarily implemented through Transport Layer Security (TLS) or Secure Sockets Layer (SSL), is the fundamental security mechanism that ensures the confidentiality and integrity of data exchanged with SOAP and REST APIs by securing the communication channel.

Web Application Firewalls (WAFs) protect against common web exploits and vulnerabilities, but they don't provide the primary transport-level encryption for API communication.