Coloured Book protocols facts for kids
The Coloured Book protocols were a special set of rules for computer networks. They were created in the United Kingdom in the 1970s. These rules helped different computer systems and networks talk to each other and share information. Each set of rules was named after the color of its instruction book cover. These protocols were used until the 1990s, when the Internet's own rules became popular everywhere.
Contents
How the Coloured Books Started
In the mid-1970s, a group called the General Post Office (GPO) in the UK worked with universities and computer companies. They wanted to create a set of standards so that different computers could work together. These standards were based on the X.25 protocol, which was used for sending data across large areas (called WANs).
The first rules were set in 1975. They improved over time, especially after trying them out on the Experimental Packet Switched Service (EPSS) in 1977. This service was run by the Post Office Telecommunications, which later became British Telecom (BT).
Where Were They Used?
The Coloured Book protocols were used on early computer networks like SERCnet starting in 1980 and SWUCN from 1982. Both of these networks later joined to form the JANET academic network in 1984. These protocols were very important for developing computer networks, especially in the UK. They were even accepted in some other countries because they were the first complete X.25 standard. This gave the UK a "several years lead" in computer networking.
When Did They Stop Being Used?
From late 1991, the Janet network started using Internet protocols instead. For a while, both the Coloured Book protocols and Internet protocols were used at the same time. But by August 1997, the older X.25 system was completely stopped.
What Were the Different Coloured Books?
The Coloured Book standards were explained in several documents. Each document covered a different part of how computers communicate. They were named by the color of their cover:
The Pink Book
The Pink Book explained rules for sending data over Ethernet networks. It used a system similar to X.25, but adapted for Ethernet.
The Orange Book
The Orange Book described rules for sending data over local networks that used the Cambridge Ring system.
The Yellow Book
The Yellow Book defined the Yellow Book Transport Service (YBTS) protocol. This was also known as the Network Independent Transport Service (NITS). It mostly worked over X.25 networks. It was developed in the late 1970s. It could also work over TCP, which is a common Internet protocol. Even the Simple Mail Transfer Protocol (SMTP), used for email, was changed to work with NITS.
The Yellow Book Transport Service helped computers find each other on the network. It used a method called source routing, where the path for the data was decided at the start.
The Green Book
The Green Book defined two ways for computer terminals (like a screen and keyboard) to connect across a network. One was an early version of what became Triple-X PAD, which worked over X.25. The other was the TS29 protocol, which was similar but worked over YBTS. These protocols were like an early version of TELNET, which lets you control a computer from far away.
The Fawn Book
The Fawn Book explained the Simple Screen Management Protocol (SSMP). This protocol helped manage how information was shown on computer screens.
The Blue Book
The Blue Book defined the Network-Independent File Transfer Protocol (NIFTP). This was similar to the Internet's FTP, which is used to send files between computers. NIFTP worked over YBTS. Unlike Internet FTP, NIFTP was made for sending many files at once (called batch mode) rather than for quick, back-and-forth use (called interactive usage).
The Grey Book
The Grey Book defined the rules for sending e-mail messages. It did not handle file transfers, as some people mistakenly thought. It worked by using the Blue Book FTP system.
The Red Book
The Red Book defined the Job Transfer and Manipulation Protocol (JTMP). This was a way for computer tasks (or "jobs") to be sent from one computer to another. It also allowed the results of these tasks to be sent back to the original computer, or even to a different one. This protocol also worked using the Blue Book FTP system.
Why Are They Still Important?
As technology changed, many ideas from the Coloured Book protocols were used in bigger, international standards. They are an important part of how computer networking grew. They show an early effort to create rules for computers to communicate well.
One interesting thing about the Coloured Book protocols was how computer addresses were written. They used a reverse domain name notation. For example, an address might look like user@UK.AC.HATFIELD.STAR instead of the Internet's way: user@star.hatfield.ac.uk.
See also
- Internet in the United Kingdom § History
- Protocol Wars
