Which protocol does NETCONF operate under?

NETCONF is a network management protocol designed to provide an interface for managing network devices. It is specifically built to operate primarily over SSH (Secure Shell). SSH is chosen because it offers a secure and encrypted channel, thereby ensuring that the configuration data and operations conducted using NETCONF are protected from eavesdropping and tampering.

The use of SSH is crucial as network devices often manage sensitive configurations and commands; thus, a secure transport protocol is necessary to maintain integrity and confidentiality. The combination of NETCONF's capabilities for fine-grained control over configurations and the secure nature of SSH makes it an effective solution for modern network management practices.

While other protocols mentioned, such as HTTP, TCP, and SMTP, serve their own purposes in networking and communications, they lack the specific focus on security that SSH provides for the NETCONF protocol. HTTP, for example, does not inherently offer the level of security required for sensitive network management commands.