Carl Hutzler’s Blog

The OLPC is a sub $200 laptop created with the goal of providing a laptop to every child in the world. Right now you can buy two of them for $400 and they will ship one to you and the other to a child in a part of the world that needs one.

The machine is fairly nice. It has Wifi, ethernet, USB ports, sound in/out, a decent screen which even works in the bright sunlight, a still/video camera, a nice battery, and more. It really is a lot of machine for the money. It includes a web browser and several applications for kids to learn how to work with computers like how to program, memory games, music composition, and more. And if you are at all linux savvy you can install other stuff too (the operating system is linux although you don’t have to be a geek to make the machine work). Their help site (wiki.laptop.org) is very well done and has great information too.

I just bought one (and donated one) because I think my son will love having his own laptop. I was even showing him something last night called “Turtle Graphics” which is programming language (formally called LOGO) on my computer and he was very interested in how to make the turtle draw what he wanted….and LOGO is built into the OLPC. It even has the PYTHON programming language built in which is what makes most of the web work! What a great thing to learn. And it comes with a number of games and funner stuff too like the ability to compose music.

So, if you haven’t found the perfect gift yet and are interested in something that is both educational and also might help a kid somewhere else in the world, this might be a great idea.

http://laptop.org/

As you can probably see from the last 4 posts, I am playing around with podcasting. Its very easy to upload an MP3 file to your blog and have it become a podcast. You just go over to Feedburner.com and give them the normal RSS feed for your blog. Feedburner will then massage it into the right RSS format for iTunes and other applications to consume as a podcast.

One small downside is that the normal RSS feed for my blog has ALL of my posts in it. What if I had a link to an MP3 in a post that I did NOT want in my podcast?? I was interested in how I could segregate those posts. Turns out its simple. If you apply a category (tag) to your podcast postings (like category=podcast) then you can very easily have wordpress create an RSS feed for just that category. Below is such an RSS feed link for my blog. I have all my test podcasts under a category called “podcast”…

http://carlhutzler.com/blog/category/podcast/feed

I then tell feedburner to digest the above RSS feed and produce an MP3 Podcast feed which gets published as:

http://feeds.feedburner.com/CarlHutzlersBlog

Add in the special itns:// service delineation and you have a podcast rss feed that will automatically open itunes and subscribe the person to your podcast with just one click. Cool :-)

itns://feeds.feedburner.com/CarlHutzlersBlog

So I looked into why my blog was slow to load the last few weeks or so. It turned out the header background graphic (fall leaves) was a 340KB PNG file and it was adding 300+ KB of extra data that was not needed. So I changed it to a JPG with a lot of compression and its now just 16KB. Granted I still have some big graphics in a few of my recent posts which still yields 1MB initial load. But other than going through a lot of extra steps in my image posting process, this is just life. At least it is down from 1.4 MB which is a 30% savings.

But I started to wonder why the Wordpress theme I am using (or perhaps its Wordpress’s default?) uses a PNG instead of a JPG? The only time I think to use PNG is when I need an image with transparency so that the background shows through. Sometimes I use GIF but more and more I use PNG as it has transparency and I believe PNG can show more colors.

But as far as I can see, this banner/background image has no need for transparency. And since PNG is a lossless compression, it yields fairly large file sizes compared to JPG. Am I missing something? Are there other considerations?

My Conservatory Ballet client wanted to sell tickets online to some upcoming performances of the Nutcracker Ballet. I guess doing it all by hand as they have done in the past (phone calls, running a credit card, recording who paid, etc) is a pain in the you know. So with just 4 days notice :-) they asked if I could whip something up.

I took a quick look around and was overwhelmed by the number of shopping cart programs available. Everything from a service to software to freeware. I tried to ensure the package I was going to use had inventory management and could take paypal payments. You need inventory control to sell tickets of course. And Paypal is just easy to set-up on such short notice.

I went with Zen Cart and have been reasonably pleased. The software seems robust and the shopping experience is very professional and amazingly full featured. And the price was $0!

My only complaint about the program is that the admin interface is very poorly organized. Trying to find a setting for this or that is a 10-15 minute exploration. There are just zillions of options and its not clear what category the option you need is located under. I usually had more success Googling it and seeing someone elses frustration trying to do the same thing along with a reply from someone who happened to know how.

Not sure I would want to run a store with 1000’s of items for sale using Zen Cart, but for something small like we are doing, it worked out just fine. Take a peek if you like…and if you are in the Washington DC area, you should consider buying a ticket. The show is held at the amazing Madeira School overlooking the Potomac in Great Falls, Virginia. The view is worth the price alone….but the show (the 35th production) will be amazing too!

http://conservatoryballet.com/tickets/

Added @11:30am 11/30: Found out that we also need to allow for a 10% discount for purchases of >10 tickets. Zen Cart can discount a single product but did not have the ability to discount an entire shopping cart. Since we wanted the discount to apply for any mix of adult/child and show time tickets, I thought we were stuck. But then I found a free module called Quantity Discounts. After installing the code and activating it under modules, I applied a 10% discount to the cart for >10 items and viola!

I heard this explanation a while back and got the text again from this Space Shuttle Page. I can’t say I know for sure if it is true, but I bet it is fairly accurate.

The US Standard railroad gauge (distance between the rails) is 4 feet, 8.5 inches. That’s an exceedingly odd number. Why was that gauge used? Because that’s the way they built them in England, and the US railroads were built by English expatriates. Why did the English people build them like that? Because the first rail lines were built by the same people who built the pre-railroad tramways, and that’s the gauge they used. Why did they use that gauge then? Because the people who built the tramways used the same jigs and tools that they used for building wagons, which used that wheel spacing.

Okay!

Why did the wagons use that odd wheel spacing? Well, if they tried to use any other spacing the wagons would break on some of the old, long distance roads, because that’s the spacing of the old wheel ruts. So who built these old rutted roads? The first long distance roads in Europe were built by Imperial Rome for the benefit of their legions. The roads have been used ever since.

And the ruts?

The initial ruts, which everyone else had to match for fear of destroying their wagons, were first made by Roman war chariots. Since the chariots were made by, or for, Imperial Rome they were all alike in the matter of wheel spacing. Thus we have the answer to the original questions:

The United States standard railroad gauge of 4 feet, 8.5 inches derives from the original specification for an Imperial Roman army war chariot. Specs and Bureaucracies live forever. So the next time you are handed a specification and wonder what horse’s ass came up with it, you may be exactly right! - because the Imperial Roman chariots were made to be just wide enough to accommodate the back-ends of two war horses.

But there’s more to this story…

When we see a Space Shuttle sitting on the launch pad, there are two big booster rockets attached to the sides of the main fuel tank. These are the solid rocket boosters, or SRBs. The SRBs are made by Thiokol at a factory in Utah. The engineers who designed the SRBs might have preferred to make them a bit fatter, but the SRBs had to be shipped by train from the factory to the launch site. The railroad line to the factory runs through a tunnel in the mountains. The SRBs had to fit through that tunnel. The tunnel is slightly wider than a railroad track, and the railroad track is about as wide as two horses’ behinds. So a major design feature of what is arguably the world’s most advanced transportation system was determined by the width of a horse’s ass.

As a follow-up to my Jamestown post, one of the things we learned was where the sailing term “Knot” came from. I have always known that a knot is 15% smaller than the same speed in miles/hour. But where did that term come from?

Below is what the sailing term “a Knot” is based off of. The sailor used a spool of rope like the one shown below. They put the end of the rope with the wooden “paddle” in the water and allowed it to un-spool with the speed of the ship. They timed the process with a sand timer (about 30 seconds) and then counted the number of actual knots that had been spooled into the water (the knots are on the rope and you can see one of them on the right side of the spool). They used this in the 1700’s to get from England to the “New World”.

Today I use a wrist watch which receives microwave signals from a constellation of 30+ satellites which can tell me within 15 feet where I am anywhere on earth.

Oh, and this marvel of technology can still tell me how fast I am going in Knots!!!

Email Submission Operations: Access and Accountability Requirements :-)

Network Working Group                                         C. Hutzler
Request for Comments: 5068
BCP: 134                                                      D. Crocker
Category: Best Current Practice              Brandenburg InternetWorking
                                                              P. Resnick
                                                   QUALCOMM Incorporated
                                                               E. Allman
                                                          Sendmail, Inc.
                                                                T. Finch
                               University of Cambridge Computing Service
                                                           November 2007

  Email Submission Operations: Access and Accountability Requirements

Status of This Memo

   This document specifies an Internet Best Current Practices for the
   Internet Community, and requests discussion and suggestions for
   improvements.  Distribution of this memo is unlimited.

Abstract

   Email has become a popular distribution service for a variety of
   socially unacceptable, mass-effect purposes.  The most obvious ones
   include spam and worms.  This note recommends conventions for the
   operation of email submission and transport services between
   independent operators, such as enterprises and Internet Service
   Providers.  Its goal is to improve lines of accountability for
   controlling abusive uses of the Internet mail service.  To this end,
   this document offers recommendations for constructive operational
   policies between independent operators of email submission and
   transmission services.

   Email authentication technologies are aimed at providing assurances
   and traceability between internetworked networks.  In many email
   services, the weakest link in the chain of assurances is initial
   submission of a message.  This document offers recommendations for
   constructive operational policies for this first step of email
   sending, the submission (or posting) of email into the transmission
   network.  Relaying and delivery entail policies that occur subsequent
   to submission and are outside the scope of this document.

It’s evidently very new. I could not get it on my regular Gmail account, but I did get it on my hosted domain account….and I had to login and logout and re-login again before it showed in the preferences.

Haven’t tried it yet, but if Gmail’s IMAP works as advertised (and I expect it will) this is a fantastic addition to gmail allowing you to keep your inbox in sync across mobile devices, desktop mail clients, and gmail’s web client.

Follow-up: I tried it and it works just as you would expect with Thunderbird. I will have to try it with my wife’s hacked iPod Touch later. It’s late :-)

According to Apple (and engadget.com) they have sold 1.4 million iPhones so far. But the interesting thing is that 250,000 of them are NOT registered for use on AT&T’s network. That is a lot of unlocked iPhones!

Are they all being used in the States on T-Mobile or are people buying them and shipping them overseas to places where Apple has yet to launch the iPhone? Likely the latter is my guess.

I wonder how much an iPhone costs Apple to make. I wonder if they lose money if they fail to get the rev-share from AT&T?

As I rambled on about a few weeks ago, I really want to see the iPhone/iPod Touch devices open up for third party applications. And while Steve J said he was working on an API for developers to allow applications (and not just via Safari) which is good, I wondered what was possible today.

So last night, I took my wife’s new shiny iPod Touch and ran a little application/applescript called iJailbreak. This application helps open up root access and SSH/SFTP access to the iPod Touch. Once you have access, you can install files on the device.

First thing you have to do is point the iPod Touch’s web browser at a specific URL which has a special TIF image file. This file was created to exploit some sort of buffer overflow error in Safari. Once you do this, you can run iJailBreak.

After iJailBreak is complete you have access to an installer of a bunch of open source packagaes. I installed SSH and SFTP and was immediately able to access the filesystem over the iPod’s wifi connection. From there you can install other apps that come with the default installer like games, new skins, VNC client, etc.

But the holy grail in this little effort was to install the version of Mail that the iPhone comes with. After all, if you can’t do Mail on a wireless device, what have you? I found some links to the iPhone applications v.1.1.1 (if I had an iPhone I could have pulled the apps off of that device using similar methods). Once you have these apps along with the GMM Framework and a mobile mail preference bundle you can SFTP them to the Touch and ensure you make the Mail.app executible. And Viola!

I also installed the Calendar, Gmaps, Notes, Stocks, and Weather apps as well just for completeness. Oh, and I backed up the old version of Calendar from the Touch just in case I needed that version someday….but from what I can tell, I can revert the whole iPod back to the original factory firmware fairly easily through iTunes in case I need to someday.

So we now have an iPod Touch that can:

• Email
• Connect to my VPN or any of my customer VPNs
• Screen Sharing via a VNC client
• SSH/SFTP to any machine I have an account on
• Google Maps
• Ability to enter iCal events (not just view them)

…and even an OSX like finder a few other nice things. Not bad. Please let me keep it, Steve :-)