This topic provides an overview of how users post articles. Users can post newsgroup articles using a news client such as Microsoft Outlook Express. The client connects to an NNTP virtual server and requests that an article be posted to one or more newsgroups. NNTP Service receives the connection request and through a process called authentication, verifies the user's authorization to post articles to the specified newsgroups. By default, this communication takes place over TCP port 119 and a Secure Sockets Layer (SSL) port of 563. NNTP Service then adds the article to the newsgroups and updates the newsgroup index. The following figure illustrates this process.
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