Coloured Book protocols

For the compact disc standards series, see Rainbow Books. For the series of U.S. government publications on computer security standards, see Rainbow Series.

The Coloured Book protocols were a set of computer network protocols used on the SERCnet and Janet X.25 packet-switched academic networks in the United Kingdom between 1980 and 1992. The name originated with each protocol being identified by the colour of the cover of its specification document.

After 1992, Internet protocols were adopted on the Janet network instead; they were operated simultaneously for a while, until X.25 support was phased out entirely in August 1997.[1]

Protocols

The standards were:

One famous quirk of Coloured Book was that components of hostnames were backwards compared to the Internet standard. For example, an address might be acc@UK.AC.HATFIELD.STAR instead of acc@star.hatfield.ac.uk. For more information, see JANET NRS.

The Yellow Book Transport Service was somewhat misnamed, as it does not fulfill the Transport role in the OSI 7-layer model. It really occupies the top of the Network layer, making up for X.25's lack of NSAP addressing at the time (which didn't appear until the X.25(1980) revision, and wasn't available in implementations for some years afterwards). YBTS used Source routing addressing between YBTS nodes—there was no global addressing scheme at that time.

Notes

  1. "Janet(UK) Quarterly Report to the Janet Community: July 1997 to September 1997". Janet webarchive. 1997. Archived from the original on February 16, 2012.

References

External links

This article is issued from Wikipedia - version of the Thursday, March 31, 2016. The text is available under the Creative Commons Attribution/Share Alike but additional terms may apply for the media files.