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Comments from Frankston, Reed, and Friends
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Saturday, April 13, 2002 BobF at 9:22 PM [url]: The "Magic" of the Internet Arthur C Clark's comment about advanced technology being indistinguishable from magic is at the heart of much of the debate about the Internet. The Internet does indeed violate many basic assumptions. The current (April 2002) issue of Discover magazine has an article on cranks in physics - how do you distinguish insight from insanity. But I can't give you a URL because magazine lets me read the article on the screen but doesn't provide a reference URL. The Internet is indeed like a magic act in which the magician hides the trick in plain sight such as a performer dressed in black whose head seems to float because the clothes blend into the background. The secret of the Internet is its simplicity. If you look behind the curtain you don't find anything because everything is in front. Take email for example. It seems so sophisticated and complicated. In fact, a consortium of all of the telecommunications regulatory agencies and companies united in an effort to create a world-wide standard for email. It was called "X.400" and the effort started in the early 1980's. While waiting for X.400 there was a need for an interim protocol. Since it was only temporary, the emphasis was on expedience and just making it work. Instead of creating a whole complicated set of protocols and tools, the implementers just built a simple extension of the protocol used to type commands into a computer. The program itself is called Telnet and it is still available today. The protocol, SMTP (Simple Mail Transfer Program), is dominant used while X.400 is almost forgotten. Rather than talk about theory, why not try to send email yourself by using the Telnet program on your computer. On a Windows system you can use the "DOS" command line or run a single command from the start menu using the "run" command. You just type "telnet" followed by the name of the mail server and the word "SMTP". You can usually find the name of your mail server by looking at the setup instructions for your email service. "SMTP" is a shorthand for the number "25" which is the "port number" usually used for the SMTP service that is listening for email connections. telnet system.xyz smtp 220 system.xyz Microsoft ESMTP MAIL Service, Version: 6.0.2600.1 ready at Sun, 7 Apr 2002 19:11:46 -0400 helo 250 system.xyz Hello [32.100.237.139] mail from: You@system.abc 250 2.1.0 You@system.abc....Sender OK rcpt to: Me@system.xyz 250 2.1.5 Me@system.xyz help 214-This server supports the following commands: 214 HELO EHLO STARTTLS RCPT DATA RSET MAIL QUIT HELP AUTH BDAT VRFY data 354 Start mail input; end with <CRLF>.<CRLF> To: Whomever From: Your Deity Subject: You shall Date: Jan 1, 2099 This is a message from your future! Do as I say! . 250 2.6.0 <SYSTE00000d6@system.xyz> Queued mail for delivery The lines with yellow background come from the mail server. Don't be confused if things don't work quite right. The telnet program might, for example, not show you what you are typing. These are easily fixed or you can just type "blind" since it's OK to make mistakes because the mail server is very forgiving. And that, too, is an important part of the Internet philosophy since, after all, we're all learning as we go and how can you learn if you never make mistakes? There is even a "HELP" command. There really isn't anything magic about email - it is just a simple protocol for exchanging messages with no need for any server provider at all. I run my email server on the computer on my desk. You don't need a third party, an ISP, for email or web hosting or other services. The Internet is a very simple network in which we can directly connect to other systems. It still makes sense to buy services from others but you can choose to buy them from anyone, anywhere, on the network, not just your access provider. Not only is there no requirement for a PTT (or Postal Service) in the middle, this method for sending email is only a convention agreed to by consensus. The actual email message format itself is very simple, there is a header consisting of lines with :'s separating a field name and the contents. If it is too long you can continue it on the next line by putting a tab or space at the beginning of the line. A blank line ends the header and the rest of the message is text. You end the message with a line that has just a ".". One minor complication is that if a line starts with a ".", you must type "..". That's it. Note that the header itself contains no indication of who actually sent the letter. That's in the "envelope" represented in the "rcpt to" command. To keep things simple I'll stop here rather than exploring the implications of this simplicity. The big difference between the Internet and traditional systems is that it is so very simple and this simplicity is the defining characteristic. The simplicity makes the Internet very resilient whereas traditional telecommunications systems require careful governance in order to work. Those in the position to set policy have been taught to fear the complexity of telecommunications. This can be tragic since public policy that applies governance models from traditional telecommunications to the Internet are one of the few ways to do real damage by making the Internet brittle and backward-looking rather than resilient and full of opportunity. It is the duty of those who set policy to understand why the Internet works and the limits and dangers of trying to "do good". Thursday, April 11, 2002 DanB at 9:35 PM [url]: What it's like to ride a Segway HT Ginger I spent about two hours on a Segway HT under a variety of conditions earlier this week. I've posted pictures and written impressions on my regular web site. Read "Impressions after riding a Segway HT" parts 1 and 2. Monday, April 08, 2002 BobF at 4:38 AM [url]: So many clocks so little time Why do we have to walk around and change every clock every time we have a daylight savings change? Why can't the be like my watch and be connected? At very least they should be able to pick the time out of the air. Or, at least, pick up the time signals from various networks such as the paging network? Even better if they were simply connected to the Internet. But then they would aslo be able to query time servers... Changing all the clocks is just one of those unnecessary petty annoyances that eat away at the quatlity of life. |
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