Software

links for 2007-12-26

• Scratch | Home | imagine, program, share
  Scratch programming for children
  (tags: programming education kids software computer internet)

links for 2007-12-23

• FreeNAS: The Free NAS Server - Home
  (tags: linux server opensource software freebsd network storage nas drive filesystem hardware)

The Once and Future King

Twice each year the top 100 or so television critics in the U.S. lock themselves in a Los Angeles hotel for a couple weeks to meet all the producers and stars of TV shows being offered in the coming months. In January and July this ritual takes place, supplying content for thousands of newspaper columns and websites. But not this January, because the Writers Guild of America strike has crippled most of the (non-PBS) winter TV schedule and gloom reigns in Hollywood. Had the meeting been held (it was cancelled just last week) I was supposed to make a big presentation about New Media, explaining to America the future of TV. But now I get to explain some of it to you, instead. And the future of TV in America, my friends, is multicast.

IP Multicast is the not-so-simple carriage of the same digital signal to thousands or millions of people at the same time. This is as opposed to unicast, which can also serve millions of people but requires millions of parallel video streams to do so. Multicast was built into the structure of the Internet from the very beginning but was generally not turned on because net admins hate it as a resource hog. But one man's resource hog is another man's chance to sell a lot of new equipment, so Cisco has long been a huge supporter of multicast because it requires ever bigger and more powerful routers to implement. Years ago Cisco bought Judy Estrin's Precept Software and its IPTV product primarily to have an application that would drive the adoption of multicast in the enterprise and beyond. Only that didn't happen because net admins weren't giving in, there was no YouTube, and the x386 computers of the era really weren't capable of handling much video anyway.

IP Multicast, while it has been around forever, has mainly been a buzzword more than a reality even to companies that supposedly used it. Tibco, for example, used to proudly proclaim that it was using multicast for real-time data feeds from stock tickers or oil refinery safety valves, but I don't really think they were. Instead they were using IP tunneling to carry multicast traffic through places where multicast addressing wasn't supported. IP tunneling was a stopgap that has long justified multicast's resource hog reputation because it layered multicast atop another service, making everything between here and there do even more work just so we could pretend we were using multicast.

But the funny rule about IETF RFCs (Internet Engineering Task Force Request for Comments) is that if you wait long enough just about every one will eventually be required and that's finally becoming the case with IP multicast.

Here's a very simple explanation for the way that IP Multicast is supposed to work. Seinfeld episode #60, The Junior Mint (which happens to be the third most popular Seinfeld episode of all time according to some Internet poll) is assigned the Class D multicast address of 224.1.2.3. If you want to watch that episode you click on it in some client application that "subscribes" to that address. When the show is made available on a server anywhere on a part of the net that supports multicast, you will start to receive it. All the routers between here and there look for multicast subscriptions and enable them. If no other customer at your ISP wants to see The Junior Mint, then the video isn't carried on your subnet nor is any of it cached locally. No bandwidth is used. But if one person does want to see The Junior Mint, then it is held to some extent in a local cache and available for all local subscribers.

See, multicast IS a resource hog.

But to more and more ISPs multicast is looking like the best answer to a huge bandwidth problem, while also being a sneaky way to take back control of the Internet.

The first problem ISPs are facing is that they are running out of IP addresses. Many, including Comcast (my ISP), are already reusing IP addresses on subnets and are rapidly moving toward IPv6. The second problem these ISPs are facing is they are running out of bandwidth at layers 1 and 2 of the OSI protocol stack. We're not talking so much about Internet bandwidth here but Intranet bandwidth -- bandwidth within the ISP's own cable plant -- and this loss they blame primarily on P2P file-sharing services.

In order to lower their bandwidth bills, ISPs are trying to take greater control of the way we, their customers, use our "unlimited" bandwidth. So Verizon and a lot of other DSL and wireless data providers are placing download caps on their monthly service while Comcast has been traffic shaping to limit the growth of P2P file-sharing services like BitTorrent. This is all intended less to slap us around and more to keep ISP costs in line so they can -- big secret coming -- CONTINUE TO MAKE NEARLY ALL THEIR PROFIT FROM PROVIDING INTERNET SERVICE. You think your phone company makes a lot of profit on voice and long distance or that your cable company makes a lot on carrying video channels? Think again. Comcast barely breaks even on video and makes a killing on Internet and VoIP. If cable company Internet subscriptions fall, those companies are in real trouble.

Why, then, would they risk alienating us, their customers? Because they think we are stupid, for one. And because they intend to offer us alternatives, like IP Multicast.

Both Comcast and Verizon are rapidly rolling out IP multicast, as I am sure most big cable and telephone ISPs are. Even Verizon's fiber-to-the-home service, FiOS, is moving to multicast because it was architected in a dumb way that sorely limits what should be a lot of throughput.

Let's look at the issue from the perspective of a cable company or MSO (Multiple System Operator, an operator of multiple cable television systems), which typically has 750 MHz of available bandwidth on their cable plants. They have to support analog video service since the bulk of their customers don't have digital cable service (they want that coax coming out of the wall to plug directly into their TV).

Typical analog video service is a 70-channel package. Each analog video channel consumes 6 MHz of the plant spectrum. That's 420 MHz of their 750 MHz of capacity consumed already. We'll be dead and buried before analog video service is retired, so that 420 MHz is unlikely to be recovered.

And if you're thinking the FCC decision about going all digital on February 17, 2009 is going to change this, think again. In fact, it will probably increase analog cable subscription numbers since the MSOs will have to take the digital-only signals coming from local broadcasters and convert them back to analog signals so customers can receive them. The FCC order doesn't affect cable or satellite companies.

As for digital video on cable systems, each 6 MHz analog channel devoted to digital use is good for anywhere from 28 to 40 megabits per second of bandwidth depending on the QAM implementation on that cable system. Newer or upgraded cable plants implement the newer QAM-256, and thus can pack in more data (and more digital video channels) per 6-MHz analog channel.

The cable guys are stuck with MPEG-2 video for a few more years due to the millions of set-top boxes currently deployed that are only MPEG-2 capable (no MPEG-4). This means higher bandwidth consumption for quality digital video on older systems. That will change over time but not quickly. The same goes for older satellite systems.

The folks at ESPN demand as part of their contracts that a lot of their programming on MPEG-2 systems be delivered at 5-8 MBps (SDTV resolution) compared to the 2 MBps used for most other channels. Same for pay cable services like HBO, Showtime, etc., though they are willing to accept slightly less bandwidth than ESPN because they don't have the motion issues associated with sports programming.

So replicate the current video offerings of a cable company on the digital side (70 channels for basic+), add in some analog premium channels (HBO, etc.), add some packages that entail multiple premium channels (HBO, HBO Family, HBO Signature and others), pay per view, adult, etc., on top of the analog video, and you're looking at 600+ MHz of the 750 MHz available spectrum JUST FOR VIDEO.

With everyone and their grandmother signing up for broadband plus wide use of P2P applications, these companies are honestly running short of intranet bandwidth.

For Comcast part of the answer to this problem is to move toward IP delivery of video using MPEG-4. This will allow them to reduce the amount of bandwidth required per channel PLUS implement IP Multicast. Internal audience studies at Comcast have shown that 90 percent of the customer base watches 10 percent of the available channels AND NOTHING ELSE. But Comcast can't easily dump the underutilized channels people don't watch because programming contracts with the studios require carriage and having a bunch of channels available that you never watch is part of the perceived value of the service we are paying for. Would you pay $50 per month for the seven channels you actually watch? Me neither.

Multicast solves this problem because it allocates no bandwidth to channels that aren't being watched. Multicast also solves (from the cable company's perspective) the "problem" of P2P because they'll give multicast addresses to paid content and content from movie studios and traditional TV networks that PAY for this privilege, saying that this is a preferred alternative to P2P, which will continue to be traffic shaped.

There are only two ways for today's ISPs to carry tomorrow's Internet video traffic. They can embrace wide-open P2P or they can implement IP Multicast. Which do you think they will do?

Merry Christmas.

Revolution, Not Evolution

A couple months have passed since I announced Team Cringely, my plan to win the Google Lunar X Prize by landing a rover on the Moon and driving it around. This week the first of the GLX contestants formally registered with more to follow, including Team Cringely, so it would seem that an update is in order. Mostly, though, I want to cover what has emerged as the primary motivation behind Team Cringely, which is literally preserving the entire idea of going to space, an idea that -- at least for America -- is near death.

When this adventure began it was a lark, a no-brainer (who wouldn't want to send a rover to the Moon and make a lot of money?), but I could hardly call myself a space expert in any regard. And two months of research isn't enough to make me a space expert today. But as a guy who has been evaluating technologies and technology programs for 30 years, the nature of the space culture is beginning to emerge.

On the government level, which is to say NASA, the space culture is one of risk aversion and budget preservation: all budgets are spent but most projects are cancelled. Space technology is moving forward at a very slow rate, with propulsion systems, for example, little changed from 40 years ago. Moore's Law has described many things, but serious space advancements aren't among them. The result is that hard-won knowledge has retired with the men and women who developed it and we are substantially LESS able to go to the Moon today as a nation than we were 30 years ago.

There may be other nations doing great work in space, I simply don't know.

Private space exploration has become a great hobby for Silicon Valley tycoons who bring to it fresh money, some fresh ideas, and by their sheer number compared to NASA a greater pace of change through accelerated natural selection. Yet I worry that this is a fad, that it will fade over time as space enthusiasts lose the 10 percent of their fortunes their wives will allow them to risk, then go back to building big boats or big houses, or whatever they would otherwise have done with that money.

Against this the Google Lunar X Prize is refreshingly different yet also sadly the same. Each of the teams I know about (there are many others I don't know about, so this generalization may be weak) is building a little Apollo Program, spending a LOT of money to launch an ambitious lander and rover with the promise of cracking open space, starting whole new industries, getting in on the bottom floor for a whole new economy. Only it won't, for the most part, work out that way.

The Google Lunar X Prize is $20 million. I haven't heard of a team other than Team Cringely planning to spend less than $50 million and many are in the $100 million range. This is both laudable and dangerous. It is laudable that there is so much capital available yet dangerous if that capital doesn't result in some truly significant advance in both space science AND space industry. If $1 billion is spent on Google Lunar X Prize entries, most of which can't win (there is only one first prize) and many of which will never even fly, does it help space exploration or hurt it? I suspect that it will hurt space exploration as mad money that could have been put to better use gets burned in little or no use at all.

You won't find, for example, any traditional space companies lining up to compete for this prize. Lockheed Martin and Boeing will gladly work for any team, but they "know better" than to vie for the prize themselves, because they are profit-making enterprises and they could never win the prize at a profit despite all the knowledge they would have coming into the contest.

But this doesn't at all mean I am down on the Google Lunar X Prize. Just the opposite. I think it is a fabulous gesture that will ultimately have positive results IF somebody actually wins.

Whether Google realizes it or not, they have taken a revolutionary step with this prize, because the only way to win it -- the ONLY way to win it -- is by taking a completely new approach. The safer route would have been for Google to offer a $100 million prize rather than $20 million. That would have made practical the efforts of these other teams and would have pulled one or more traditional space contractors into the race. There would be a winner and that winner would look like any one of these teams.

But for whatever reason Google decided to offer only $20 million for the first prize, giving us what will emerge over the next few months as half a dozen or more America's Cup-sized teams with America's Cup-sized budgets, each pinning its hopes on a single rover and arguing that there is a business case for investment here, somewhere, if only you squint just right.

Then there is Team Cringely. Our budget to win the Google Lunar X Prize has grown from $3 million to $5 million, where it will stop. That's because (controversial statement coming) I am firmly convinced that we can win the prize with $5 million, but if we spent $10 million we probably couldn't.

So far we have raised $500,000, with the biggest single investment being $100,000 from a guy whose motivation is to share an adventure with his nine-year-old son. It's a lot of money, sure, but this is money that will never be regretted by those who invested it because it isn't enough to have any impact on their lives -- that is unless we win the prize. It's true mad money. One Team Cringely investor is also bankrolling the iPhone Dev Team hackers group simply to pull Steve Jobs' chain.

We'll raise more money over time from similar folks and add to that some corporate sponsorships that will eventually reach our $5 million goal, I am sure. The goal is modest and within reach.

And the pitch is simple: win the prize, make money, save the future of space exploration.

The method is simple, too: build smaller, cheaper rovers and send a bunch of them to the Moon.

If you have 20 shots at hitting the Moon for $5 million versus one shot for $100 million, it changes your whole day.

And the idea is appealing to more than just giddy amateurs. Without making any effort to recruit them, Team Cringely has begun attracting real rocket scientists who are drawn by the simple idea that winning this prize at a profit could change completely the way entrepreneurs and governments look at space. The symbolism of what we are doing is as important as the work, itself.

So Team Cringely now has a Program Manager, a role I gladly hand over so I can go back to evangelizing and raising money. Our Program Manager is Tomas Svitek, who has a PhD from Caltech, was a systems engineer at the Jet Propulsion Laboratory on the NASA Mars Scout, Mars Surveyor, Mars Sample Return and various Discovery Missions. He was the Principal Scientist for Orbital Sciences Corp., Project Leader for the BlastOff Lunar Lander project and AeroAstro's miniature spacecraft project. He has managed and completed projects for NASA, the U.S. Air Force Research Lab, Microcosm Inc., and SpaceX Corp.. He was lead engineer for Jeff Bezos' Blue Origins crew capsule and has long run his own space consulting company in California.

With the help of Tomas and the rest of Team Cringely we will within 18 months land on the Moon and claim the Google Lunar X Prize. Doing so -- and doing it at a profit -- will show the world there is another way to explore space, drawing new players with new rules into this exciting future.

FlexMail

Since IMAP is not working with Google Mail and my Windows Mobile phone, I started looking into what other clients I could run on my phone.  FlexMail looked like the best option.

FlexMail integrates SMS, MMS, ActiveSync and POP/IMAP accounts.  You can see all of accounts in an integrated folder list.  Fordisplaying email messages, FlexMail handles HTML messages.  There are tons of options, so you can configure how much mail is downloaded, which way an IMAP folder should be synchronized.

Once I finished configuring it, I noticed that my phone was really starting to drag and actually crashed. Once I disabled it, my phone returned to normal.

I think that what I am going to do is configure the built-in Windows Mobile email client to check my email with POP3.  I will just have to deal with the views of my mail being out of sync on different email clients.  

 [via  Short Nerd Chief]