What protocol provides a means to manage devices using XML and a standard formatting?

The protocol that provides a means to manage devices using XML and a standard formatting is NETCONF. It is designed specifically for network configuration and management, utilizing XML to encode its messages. The key feature of NETCONF is its ability to offer a standardized way to interact with network devices, allowing for the retrieval and manipulation of device configurations.

NETCONF operates over transport protocols such as SSH, which ensures secure communication during the management process. The use of XML provides a structured and interoperable method for encoding data, which is essential for various automation tasks in network management.

While RESTCONF is also related to network management and uses REST principles along with JSON for formatting, the question specifically asks for a protocol that uses XML. Thus, NETCONF is the most appropriate choice given its focus and design for managing device configurations through XML-based data formats.