The Coloured Book protocols were a set of computer network

Computer network

A computer network, often simply referred to as a network, is a collection of hardware components and computers interconnected by communication channels that allow sharing of resources and information....

 protocols used on the SERCnet and JANET

JANET

JANET is a private British government-funded computer network dedicated to education and research. All further- and higher-education organisations in the UK are connected to JANET, as are all the Research Councils; the majority of these sites are connected via 20 metropolitan area networks JANET...

 X.25

X.25

X.25 is an ITU-T standard protocol suite for packet switched wide area network communication. An X.25 WAN consists of packet-switching exchange nodes as the networking hardware, and leased lines, Plain old telephone service connections or ISDN connections as physical links...

 packet-switched academic networks in the United Kingdom

United Kingdom

The United Kingdom of Great Britain and Northern IrelandIn the United Kingdom and Dependencies, other languages have been officially recognised as legitimate autochthonous languages under the European Charter for Regional or Minority Languages...

 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

Internet

The Internet is a global system of interconnected computer networks that use the standard Internet protocol suite to serve billions of users worldwide...

 protocols were adopted on JANET instead; they were operated simultaneously for a while, but X.25 support was phased out entirely by August 1997.

Protocols

The standards were:

• The Pink Book defined protocols for transport over Ethernet
  Ethernet
  Ethernet is a family of computer networking technologies for local area networks commercially introduced in 1980. Standardized in IEEE 802.3, Ethernet has largely replaced competing wired LAN technologies....
  
  . The protocol was basically X.25
  X.25
  X.25 is an ITU-T standard protocol suite for packet switched wide area network communication. An X.25 WAN consists of packet-switching exchange nodes as the networking hardware, and leased lines, Plain old telephone service connections or ISDN connections as physical links...
  
   level 3 running over LLC2.
• The Orange Book defined protocols for transport over local networks using the Cambridge Ring
  Cambridge Ring
  The Cambridge Ring was an experimental local area network architecture developed at the Cambridge University Computer Laboratory in the mid-late 1970s and early 1980s. It used a ring topology with a theoretical limit of 255 nodes , around which cycled a fixed number of packets...
  
  .
• The Yellow Book defined the Yellow Book Transport Service (YBTS) protocol, which was mainly run over X.25. It was developed by the Data Communications Protocols Unit of the Department of Industry in the late 1970s.
• The Green Book defined two protocols to connect terminals across a network: an early version of what became Triple-X PAD
  Packet Assembler/Disassembler
  A packet assembler/disassembler, abbreviated PAD is a communications device which provides multiple asynchronous terminal connectivity to an X.25 network or host computer. It collects data from a group of terminals and places the data into X.25 packets...
  
   running over X.25, and the TS29 protocol modelled on Triple-X PAD, but running over YBTS. It was developed by Post Office Telecommunications
  Post Office Telecommunications
  Post Office Telecommunications was set up as a separate department of the UK Post Office, in October 1969. The Post Office Act of that year was passed to provide for greater efficiency in post and telephone services; rather than run a range of services, each organisation would be able to focus on...
  
  . These protocols are similar in functionality to TELNET
  TELNET
  Telnet is a network protocol used on the Internet or local area networks to provide a bidirectional interactive text-oriented communications facility using a virtual terminal connection...
  
  .
• The Fawn Book defined the Simple Screen Management Protocol (SSMP)
• The Blue Book defined the Network-Independent File Transfer Protocol (NIFTP), analogous to Internet FTP
  File Transfer Protocol
  File Transfer Protocol is a standard network protocol used to transfer files from one host to another host over a TCP-based network, such as the Internet. FTP is built on a client-server architecture and utilizes separate control and data connections between the client and server...
  
  , running over YBTS. Unlike Internet FTP, NIFTP was intended for batch mode rather than interactive usage.
• The Grey Book defined protocols for e-mail
  E-mail
  Electronic mail, commonly known as email or e-mail, is a method of exchanging digital messages from an author to one or more recipients. Modern email operates across the Internet or other computer networks. Some early email systems required that the author and the recipient both be online at the...
  
   transfer (not file transfer as is sometimes claimed), running over Blue Book FTP.
• The Red Book defined the Job Transfer and Manipulation Protocol (JTMP), a mechanism for jobs to be transferred from one computer to another, and for the output to be returned to the originating (or another) computer, running over Blue Book FTP.

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

JANET NRS

The JANET NRS was a pseudo-hierarchical naming scheme adopted for use on British academic and research networks before the superficially similar system used by the Internet DNS had been fully established....

.

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

Source routing

In computer networking, source routing allows a sender of a packet to partially or completely specify the route the packet takes through the network...

addressing between YBTS nodes—there was no global addressing scheme at that time.

External links

• alt.folklore.computers: "What is the British Grey Book protocol?"