What protocol is used by news servers to exchange Usenet articles?

The protocol used by news servers to exchange Usenet articles is the Network News Transfer Protocol (NNTP). NNTP is specifically designed for the distribution, inquiry, and retrieval of news articles in the Usenet system. It supports the handling of multiple newsgroups and allows users to post messages, retrieve articles, and organize the data efficiently.

This protocol establishes a connection between news servers and clients, enabling the flow of information in a structured manner. This focus on handling USENET traffic sets NNTP apart as the standard for this purpose, ensuring that all interactions related to newsgroup content utilize a specific, optimized format tailored for news transfer.

While other protocols such as FTP, SMTP, and HTTP serve different functions—such as transferring files, sending emails, and retrieving web pages, respectively—they do not cater specifically to the demands of Usenet article exchanges. This distinction emphasizes why NNTP is recognized as the appropriate protocol for handling news articles.