Internet explained for members of the Carlyle Gardens Computer Club. I encourage club members familiar with internet issues to write an article for these pages.

The Internet is simply lots of smaller computer networks (like the ones in the Computer Room) all connected together, and all talking with each other.

The USA Defense Advanced Research Projects Agency (DARPA) paid for ARPANET, the 1969 predecessor of the Internet. ARPANET taught a lot about how to connect multiple different computer networks using packet switching over circuit switched telephone lines. A workable Internet protocol suite was devised and tested between 1973 and 1977.

Communication Protocols are a fancy word for agreements about how to talk with each other. Which language to use, who you are talking to, what time it is there, whose turn it is. Pretty much like a conversation at a party, except that computers are really stupid. They need to be told exactly how to have a conversation. They need a formal protocol.

Each computer company once had its very own local area network protocols, and usually their own cables. Apple had AppleTalk. IBM had Token Ring. Microsoft Windows had Server Message Block (SMB) also known as Common Internet File System (CIFS) running over NetBios and NetBUI. Novel had NetWare. Unix often used Network File System (NFS) to access remote files. A Tower of Babel.

Ethernet (1980) became a standard, and now pretty much all local area networks run on Ethernet wiring (or wirelessly). Eventually almost everyone also agreed to support Transmission Control Protocol and Internet Protocol (TCP/IP) for internet connections.

Running over TCP/IP are applications such as File Transfer Protocol (FTP), which lets us transfer files (such as web pages) to a web server. Your web browser can download files (such as new programs) from a file server via FTP.

Other well known applications show your email using Post Office Protocol (POP) or Internet Message Access Protocol (IMAP). Your email is transferred using Simple Mail Transfer Protocol (SMTP).

Web servers use the HyperText Transfer Protocol, invented by Sir Tim Berners-Lee in 1989.

The Internet Society guides and funds the Internet Engineering Task Force (IETF). The IETF maintains the protocols in use on the Internet. Volunteers produce Request for Comment (RFC), which describe standards for various internet protocols.

IETF work in conjunction with International Organization for Standardization (ISO), and the World Wide Web Consortium (W3C).

The World Wide Web Consortium (W3C) set standards for the World Wide Web (WWW). The consortium is made up of member organisations which maintain full-time staff for the purpose of working together in the development of standards for the World Wide Web. W3C was founded in 1994 by Sir Tim Berners-Lee. He also invented the World Wide web.

The W3C also provides validators to confirm your web pages are valid and meet standards. If your web page is not valid, it is often very hard to work out why a web browser is not displaying it correctly.

When we seek a web resource, how do we translate the Internet Protocol address numbers computers use to identify each other into a domain name we humans find comfortable? We do it via the Domain Name System (DNS).

The Internet Assigned Numbers Authority (IANA) delegates number assignment to five Regional Internet registries. They in turn delegate assignment to a Domain Name Register. I bought our computer club name from a Domain Name Register in the USA. Our name costs about US$12 a year.

IANA registries also delegate more local Domain Name Servers. Usually our local Internet Service Provider tells our computer the number it needs for a connection to a web site. We do not need to worry about numbers, unless something goes wrong.

As an aside, last year we ran out of internet numbers on IPv4, the current internet numbering system. There were only four billion IPv4 numbers, and that was not enough. There is gradual progress moving to IPv6. This should not run out of numbers soon, as it permits around 3.4 times 10 to the 38th power numbers.

One of many Uniform Resource Schemes registered with IANA is the top level for Uniform Resource Identifiers (URI) - formerly called Uniform Resource Locators (URL). As well as the computer, it may include a path to a resource. You may be calling that mouthful a web address.