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The TCP/IP Guide  9  TCP/IP Application Layer Protocols, Services and Applications (OSI Layers 5, 6 and 7)       9  TCP/IP Key Applications and Application Protocols            9  TCP/IP File and Message Transfer Applications and Protocols (FTP, TFTP, Electronic Mail, USENET, HTTP/WWW, Gopher)                 9  Usenet (Network News) and the TCP/IP Network News Transfer Protocol (NNTP)                      9  Usenet Overview, Concepts and General Operation

Usenet Addressing: Newsgroups, Newsgroup Hierarchies and Types 1 2 3 TCP/IP Network News Transfer Protocol (NNTP)

Additional Usenet Headers

Usenet messages may also contain additional headers, just as is the case with e-mail messages. Some of these headers are entirely “custom” and are included by individual users to provide extra information about an article. Others are used in many or even most current Usenet articles, and have become almost “de facto” standard headers through common use. Many of these custom headers are preceded by “X-”, indicating that they are “experimental” or “extra” headers.

Some of the more frequently encountered “additional” Usenet headers are shown in Table 265.

Since Usenet follows the RFC 822 standard, Multipurpose Internet Mail Extensions (MIME) can be used to format Usenet messages. When this is done, you will see the usual MIME headers (such as MIME-Version, Content-Type and so forth) in the message.

Note that the use of MIME in Usenet messages is somewhat controversial. Some newsreaders are not MIME-compliant and make a mess when trying to display some of these messages, and many Usenet veterans object to the use of anything but plain text in Usenet messages. Despite this, MIME messages are becoming more common, for better or worse.

Usenet Addressing: Newsgroups, Newsgroup Hierarchies and Types 1 2 3 TCP/IP Network News Transfer Protocol (NNTP)