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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 Application Layer Addressing: Uniform Resource Identifiers, Locators and Names (URIs, URLs and URNs)                 9  Uniform Resource Locators (URLs)

URL General Syntax 1 2 3 4 5 URL Relative Syntax and Base URLs

Network News / Usenet URL Syntaxes (news)

Two syntaxes are defined for URL specification of Usenet (NetNews):

news://<newsgroup-name>
news://<message-id>

Both of these URLs are used to access a Usenet newsgroup or a specific message, referenced by message ID. Like the “mailto” scheme, this is a special type of URL because it defines an access method but does not provide the detailed information to describe how to locate a newsgroup or message.

By definition, the first form of this URL is interpreted as being “local”. So for example, “news://alt.food.sushi” means “access the newsgroup alt.food.sushi on the local news server, using the default news protocol”. The default news protocol is normally NNTP (see below). The second URL form is global, because message IDs are unique on Usenet (or at least, are supposed to be!)

This is a different URL type for news access:

nntp://<host>:<port>/<newsgroup-name>/<article-number>

Unlike “news”, this URL form specifically requests the use of NNTP and identifies a particular NNTP server. Then it tells the server which newsgroup to access and which article number within that newsgroup. Note that articles are numbered using a different sequence by each server, so this is still a “local” form of news addressing. The port number defaults to 119.

Even though the “nntp” form seems to provide a more complete resource specification, the “news” URL is more often used, because it is simpler. It's easier just to set up the appropriate NNTP server in the client software once than to specify it each time, since clients usually only use one NNTP server.

URL General Syntax 1 2 3 4 5 URL Relative Syntax and Base URLs