This header line shows the version of the program responsible for the transmission of this article over the immediate link, that is, the program that is relaying the article from the next site. For example, suppose site A sends an article to site B, and site B forwards the article to site C. The message being transmitted from A to B would have a Relay-Version header identifying the program running on A, and the message transmitted from B to C would identify the program running on B. This header can be used to interpret older headers in an upward compatible way. Relay-Version must always be the first in a message; thus, all articles meeting this standard will begin with an upper case "R". No other restrictions are placed on the order of header lines.
The line contains two fields, separated by semicolons. The fields are the version and the full domain name of the site. The version should identify the system program used (e.g., "B") as well as a version number and version date. For example, the header line might contain
Relay-Version: version B 2.10 2/13/83; site cbosgd.UUCP
This header should not be passed on to additional sites. A relay program, when passing an article on, should include only its own Relay-Version, not the Relay-Version of some other site. (For upward compatibility with older software, if a Relay-Version is found in a header which is not the first line, it should be assumed to be moved by an older version of news and deleted.)