Monday, November 16, 2009

history of email


history of email



Email is much older than ARPANet or the Internet. It was never invented; it evolved from very simple beginnings.

Early email was just a small advance on what we know these days as a file directory - it just put a message in another user's directory in a spot where they could see it when they logged in. Simple as that. Just like leaving a note on someone's desk.

Probably the first email system of this type was MAILBOX, used at Massachusetts Institute of Technology from 1965. Another early program to send messages on the same computer was called SNDMSG.

Some of the mainframe computers of this era might have had up to one hundred users -often they used what are called "dumb terminals" to access the mainframe from their work desks. Dumb terminals just connected to the mainframe - they had no storage or memory of their own, they did all their work on the remote mainframe computer.

Before internetworking began, therefore, email could only be used to send messages to various users of the same computer. Once computers began to talk to each other over networks, however, the problem became a little more complex - We needed to be able to put a message in an envelope and address it. To do this, we needed a means to indicate to whom letters should go that the electronic posties understood - just like the postal system, we needed a way to indicate an address.

This is why Ray Tomlinson is credited with inventing email in 1972. Like many of the Internet inventors, Tomlinson worked for Bolt Beranek and Newman as an ARPANET contractor. He picked the @ symbol from the computer keyboard to denote sending messages from one computer to another. So then, for anyone using Internet standards, it was simply a matter of nominating name-of-the-user@name-of-the-computer. Internet pioneer Jon Postel, who we will hear more of later, was one of the first users of the new system, and is credited with describing it as a "nice hack". It certainly was, and it has lasted to this day.

Despite what the world wide web offers, email remains the most important application of the Internet and the most widely used facility it has. Now more than 600 million people internationally use email.

By 1974 there were hundreds of military users of email because ARPANET eventually encouraged it. Email became the saviour of Arpanet, and caused a radical shift in Arpa's purpose.

Things developed rapidly from there. Larry Roberts invented some email folders for his boss so he could sort his mail, a big advance. In 1975 John Vital developed some software to organize email. By 1976 email had really taken off, and commercial packages began to appear. Within a couple of years, 75% of all ARPANET traffic was email.

Email took us from Arpanet to the Internet. Here was something that ordinary people all over the world wanted to use.

As Ray Tomlinson observed some years later about email, "any single development is stepping on the heels of the previous one and is so closely followed by the next that most advances are obscured. I think that few individuals will be remembered." That's true - to catalogue all the developments would be a huge task.

One of the first new developments when personal computers came on the scene was "offline readers". Offline readers allowed email users to store their email on their own personal computers, and then read it and prepare replies without actually being connected to the network - sort of like Microsoft Outlook can do today.

This was particularly useful in parts of the world where telephone costs to the nearest email system were expensive. (often this involved international calls in the early days) With connection charges of many dollars a minute, it mattered to be able to prepare a reply without being connected to a telephone, and then get on the network to send it. It was also useful because the "offline" mode allowed for more friendly interfaces. Being connected direct to the host email system in this era of very few standards often resulted in delete keys and backspace keys not working, no capacity for text to "wrap around" on the screen of the users computer, and other such annoyances. Offline readers helped a lot.

The first important email standard was called SMTP, or simple message transfer protocol. SMTP was very simple and is still in use - however, as we will hear later in this series, SMTP was a fairly naïve protocol, and made no attempt to find out whether the person claiming to send a message was the person they purported to be. Forgery was (and still is) very easy in email addresses. These basic flaws in the protocol were later to be exploited by viruses and worms, and by security frauds and spammers forging identities. Some of these problems are still being addressed in 2004.

But as it developed email started to take on some pretty neat features. One of the first good commercial systems was Eudora, developed by Steve Dorner in 1988. Not long after Pegasus mail appeared.

When Internet standards for email began to mature the POP (or Post Office Protocol) servers began to appear as a standard - before that each server was a little different. POP was an important standard to allow users to develop mail systems that would work with each other.

These were the days of per-minute charges for email for individual dialup users. For most people on the Internet in those days email and email discussion groups were the main uses. These were many hundreds of these on a wide variety of topics, and as a body of newsgroups they became known as USENET.

With the World Wide Web, email started to be made available with friendly web interfaces by providers such as Yahoo and Hotmail. Usually this was without charge. Now that email was affordable, everyone wanted at least one email address, and the medium was adopted by not just millions, but hundreds of millions of people.









history of computers, networks and modems


history of computer




The most ancient processing device humans have invented would probably be the abacus, dating back to about 3000BC. But more realistically we should look to the 1940s for the origins of the computer.

During World War 2, both the UK government, in the form of a computer called Colossus, and the US government in the form of ENIAC ( or the Electronic Numerical Integrator Analyzer and Computer) developed precursors of todays computers. The invention of the transistor in 1947 gave these developments a great leap forward.

In the 1960s we saw the beginnings of companies that were to have a major influence in the computing field - Texas Instruments, Fairchild computing, and IBM, whose 360 computer was released in 1964.

The sort of computers ARPANET and the early research networks were dealing with were monsters with very little power by today's standards. Only computer scientists used them. Computers with the power of modern day pocket calculators occupied whole floors of buildings. I think at the time IBM predicted the world would only need 13 of them for planet Earth for all time!

These monsters, or mainframes as they are called where they still exist these days, could only be afforded by large institutions.

Another big event happened in 1963 - the invention of the mouse by Douglas Englebart. Engelbart was a very influential and visionary person, who also helped develop early word processors and hypertext. However it would be almost another 20 years before most of his inventions became popular or much used. These had to wait for the personal computer to appear.

There might have been an Internet without personal computers, but it would have been uninteresting, and probably confined to the research community and computer scientists. The invention that gave the Internet a real chance to reach out to over 600 million people, and to make it the sort of network it is today, was the personal computer. Personal computers, networked over the global telephony infrastructure, is what created the network we have today.

The first personal computer, the Altair 8800, cost 379 US dollars and was shipped in January 1975. Over 1000 were sold. By 1977 The Radio Shack TRS 80, Apple 2, and Commodore PET were also on the market. IBM got the idea by about 1981 and released the first IBM PC.

The company that dominated the market in the early days - at one stage they had 75% of all computers sold - was Apple Computer. Apple was founded by Steve Jobs and Steve Wozniak just outside of San Francisco. Steve Jobs at the time was a long haired vegetarian - Steve Wozniak was to lose a fortune on back-to-Woodstock concerts. So the influences of the San Francisco flower power hippy culture of the time were there.

The early computer programmers called themselves hackers. At one stage Bill Gates would have been proud to be called a hacker. They called the software they created "hacks".

The original Apple operating system was called AppleDOS, but by 1980 the CP/M operating system had become a popular addition to the Apple 2+. It was very like the competitor which was to overtake it and launch Bill Gates on the way to his fortune, MSDOS. In fact, MS-DOS's predecessor was called "Q-DOS" - short for "Quick and Dirty Operating System"..

Early computers featured a thing called a "command line". They didn't yet have a mouse, although joysticks for games machines were starting to appear. We had to wait for the 1990s before Windows became popular on the IBM operating system.

None of these computers - either the new PCs or the old mainframes - had been designed to be communicating devices (the main objective was thought to be their processing power). So a means had to be found to connect them to networks. Here two more developments became important - the modem, which connected early computers to telephone lines, and Ethernet, a standard which was developed for "Local area networks" or LANs (where computers were really all in the same room or area and could be "wired" together).

Modems
and networks






Modem is a term we are likely to forget soon in the digital age, but for most of us modems were where internetworking began. Modem is short for modulate-demodulate - that's where it got its name. Modems enable the digital form of matter that a computer uses to communicate by the analogue form of transmission of old style telephone systems.

There were apparently some early modems used by the US Air Force in the 1950's, but the first commercial ones were made a decade later. The earliest modems were 75 bps (or bits per second). That's about 1/750th of the speed of current modems, so they were pretty slow! But to early networking enthusiasts, modems were 300 bps. Then came 1200, and by 1989 2400 bps modems.

By 1994, domestic modems had got to 28.8 kilobits per second - which was just as well, because by then we were beginning to send more than text messages over the Internet. This was thought to be an upper limit for phone line transmissions. But along came the 56k modem, and a new set of standards, so the speeds continue to push the envelope of the capacity of the telephone system.

So much so that many of have moved on, into wireless networks, and into "broadband" systems, which allow much faster speeds. But modems made the first critical link between computers and telephones, and began the age of internetworking.

Another of the former Arpanet contractors, Robert Metcalfe, was responsible for the development of Ethernet, which drives most local area networks.

Ethernet essentially made a version of the packet switching and Internet protocols which were being developed for Arpanet available to cabled networks. After a stint at the innovative Xerox Palo Alto laboratories, Metcalfe founded a company called 3-Com which released products for networking mainframes and mini computers in 1981, and personal computers in 1982.

With these developments in place, tools were readily available to connect both old and new style computers, via wireless, cable, and telephone networks. As the networks grew, other companies such as Novell and CISCO began to develop more complex networking hubs, bridges, routers and other equipment. By the mid 1980's, everything that was needed for an explosion of inter networking was in place.