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Games

Palm Pre and WebOS Get Native Gaming 49

rboatright writes "WebOS developers have been waiting, and with the 1.3.5 release, Palm's open source page suddenly listed SDL. Members of the WebOS internals team took that as a challenge and within 24 hours had a working port of Doom running in SDL on the Pre, in a webOS card. 48 hours later, they not only had Quake running, but had found in the latest LunaSysMgr the requirements to launch a native app from the webOS app launcher from an icon just like any other app. At the same time, the team demonstrated openGL apps running. With full native code support, with I/O available via SDL, developers now have a preview into Palm's future intent with regard to native code SDK's, and a hint of what's coming."

Comment Shade-Grown Train-Killed Solar-Grilled BBQ (Score 1) 416

Gee, I love the idea of the solar cells being "above the track". Wild animals from lizards on up are smart enough to seek out the shade, as are vagrant livestock. So, with the tracks in the shade for a good part of the day, I expect we could have a chain of Momma's Train-Killt Bar-B-Q stands all the way from Tucson to Phoenix (Cook them in solar ovens, come to think of it.) Or maybe DARPA could fund a next-generation cow catcher on the front of the engine, one that works at 200mph...

Comment Goats can do what mowers can't (Score 5, Informative) 466

There are lots of places in the Bay Area that do this. It's much more than a sop to carbon neutrality: the goats can "mow" slopes that are far too steep and uneven to wrestle a mower across. They also make short work of areas that are filled with rocks, brush and stumps and have no objection to a dessert course of poison oak (that's a good reason not to pat them on the head, though).

I used to watch them arrive at the Lawrence Hall of Science up in the Berkeley hills. Trailers pull up; the goat wranglers set out a low fence and then unload the goats and a few working dogs. Over the next few days the wranglers move the fenced area across the slope and the goats eat and fertilize their way across the landscape. A few days after they arrive the brush is gone and some very nasty terrain has become a fire break, with roots still in place to prevent land slides. What's not to love?

Comment It's not spanning tree's fault (Score 1) 388

A $30 switch and a patch cable will take down your spanning-tree enabled infrastructure very effectively. Loop the cable on your cheap switch: voila, a broadcast-storm generator. Plug it into the wall; plug your laptop into the switch and let it DHCP Discover, which is a broadcast. Your cheap switch now generates a stream of broadcasts as fast as it can, injecting them into the network. Your Spanning-Tree Enabled switches now repeat the broadcast faithfully. Network crashes*. STP prevents your switches from creating loops, NOT from propagating broadcast storms...

*unless you are throttling the ports based on broadcast traffic, which you now know is NOT a feature of Spanning Tree

Education

Submission + - Monkeys and humans learn the same way (sciencedaily.com)

Lucas123 writes: "A new study from UCLA showed that monkeys, like humans, learn faster by being actively involved in the learning process rather than just having information placed before them, according to a story in ScienceDaily. In the study, two rhesus macaque monkeys learned to put up to 18 photos on an ATM-like touch screen in a row. 'The monkeys did much better on the first three days when they had the help than when they didn't, but on the test day, it completely reversed.'"

Feed Engadget: Deep-brain electrical stimulation brings man out of vegetative state (engadget.com)

Filed under: Misc. Gadgets

A 38-year-old man who had been in a near-coma for six years was recently awakened via the use of a pacemaker and two electrodes which were implanted deeply in his brain. The electrical device, manufactured by a company called Medtronics, was used to send impulses to the area of the brain regulating consciousness, and researchers believe that the stimulation may be enhancing brain circuits that are still capable of functioning. The man, the first of 12 to undergo the procedure, has gone from a vegetative state to being able to play cards, speak with family members, and take trips outside. While this isn't exactly a new technology -- as doctors have been experimenting with deep-brain stimulation in the treatment of Parkinson's, epilepsy, and brain injuries for some time -- it is a clear sign that there's hope for patients whom the medical community has been, heretofore, unable to treat.

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Office Depot Featured Gadget: Xbox 360 Platinum System Packs the power to bring games to life!


Feed Techdirt: Beam Me Up Otis: Teams Getting Set To Take Another Shot At Space Elevator Prize (techdirt.com)

Despite the fact that it sounds like something straight out of a bad sci-fi novel, there are a number folks who believe that space elevator technology represents that best way for humans to cheaply and conveniently explore outer space. As with other "out there" ideas, NASA has started holding contests to promote innovations in the area. The challenge for the teams isn't to actually build a full-fledged space elevator (that probably won't be for a while), but to build a robot that can hoist itself up 100 meters in the air on a thin carbon tether in 50 seconds. Last year, a team from Canada failed to hit the mark by just two seconds. This October, teams will have another crack at it, and assuming there's been any innovation at all, some team is likely to take home the $500,000 prize. After reaching this goal, it's just another 384,402,900 meters to go before they get to the moon!

Comment Your Bandwidth Numbers are Off! Common Mistake (Score 3, Informative) 232

Actually, Bandwidth In Mirror Will Be Larger Than It Appears (BIMWBLTIA)! And, when it gets right down to it, you don't care about bandwidth anyway; you only think you do.
1. Why do companies spend $500 a month for a 1.544Mbps T-1 when a 1.5Mbps DSL connection is only $29? BECAUSE YOU DON'T CARE ABOUT BANDWIDTH (you only think you do. more below.)
2. Why does your 64Kbps codec consume more than that when you actually look at it? BECAUSE OVERHEAD COULD DRIVE THROUGHPUT AS HIGH AS 3,500Kbps! (actually that's just a theoretical, non-real world extreme, _as is 64Kbps_, more below.)

Regarding #1. Bandwidth, schmandwidth. It's all about LATENCY. Which is better for voice, a 50Mbps pipe or a 56Kbps pipe? Answer: Cannot tell from info provided in question. If, in the 60th second of a minute-long call, I deliver 3000Mb of voice data, I've given you the promised 50Mbps bandwidth. Unfortunately, there were 59 seconds of silence followed by an auctioneer's delightful squirt of one minute's words delivered in one second! Far better if they had been delivered less dramatically, but spaced evenly, over that minute. VOICE IS DIFFERENT FROM DATA IN THIS WAY. Had that been a big file, it wouldn't have made any difference. For file-type data, you pay your provider for the bandwidth. For voice-type data, you need to find a provider who can guarantee you evenly-spaced, regular delivery: that is, low latency and jitter. A T-1 has low latency, jitter and pkt loss; a DSL pipe may have identical _bandwidth_ but comes with no guarantee as to what is really important for voice, latency-jitter-loss.
That 56Kbps pipe? If it were a plain old $20-a-month land line from the phone company, that skimpy bandwidth would be delivering your voice with an end-to-end delay (latency) of less than 150ms; compare that to the VOIP standard (again, nominal) of 450ms. Your land line is still the Gold Standard for voice quality. (And yes, I have experienced better-sounding voice over Skype; Pure Friendly Magic! Great proof that VOIP can exceed even Carrier Grade. Someday, Vladimir, someday all the workers will have Carrier Grade VOIP.)

Regarding #2. I know that XorNand mentions overhead and is obviously aware of the following, but let's be explicit: overhead is more than trivial. You will never, never, never, never deliver voice at 64Kbps with a 64Kbps codec. That is a fake number, the limit that VOIP might approach asymptotically. Worst case? Your voice, encoded at 64Kbps, consumes about 3.5Mbps of bandwidth. (Also a fake number; we make a deal with the Devil, i.e. Delay, to keep the bandwidth down.)
The phone company standard codec, G-711, samples your voice 8000 times per second and represents the volume of your voice in that sample as an 8-bit number: 8bits*8,000 samples --> 64,000bps. The phone company then drops your voice onto the wire (on say a T-1 line) 8 bits at a time; each sample drops as soon as it's encoded, eight thousand times a second. Because this wire goes straight to the Central Office (say), the Telco does not need to add an IP address: there's only one place for it to go, the other end of the wire. Because the wire has a clocking device at both ends (the CSU that terminates a T-1) the Telco does not need to attach an RTP Timestamp to your voice: the T-1 circuit does that too. Because the voice samples can't leapfrog eachother in the wire, or get lost, the Telco does not need to attach a TCP sequence number or acknowledgement; the CSUs know whether a sample is to be used as voice or data, and handle multiplexing, so there is no need for a TCP/UDP port number.
You can see where this is going, right? VOIP takes the same sample, and to deliver it attaches an RTP header for timing/sequencing/codec info, a UDP header for port number, an IP header for end-to-end addressing, and an Ethernet header to get you across your LAN. That 1-byte sample is now dozens of bytes long. It's as if to carry 8000 commuters to work you sent out 8000 trains, each with a string of locomotives to pull a single commuter down the rails. We don't do that; we wait until we accumulate a "reasonable" number of commuters on the platform, then have one string of locomotives pull many of them down the rails at once. Yes, the commuters experience delay, and Yes, delay is evil, but the alternative would be to use a ridiculous amount of bandwidth on the rail network to deliver them all.
Most VOIP systems impose a MINIMUM delay of 10ms at the beginning of the delivery process, the time it takes to collect 80 voice samples. They drop voice on the wire 100 times a second, not 8000 like a Telco T-1. At that rate, a call actually needs around 100Kbps bandwidth to carry the 64Kbps of voice you encoded with G-711. If you wait five times as long, collect 400 samples and drop them on the wire in one ethernet frame, you'll drop 20 frames per second and your bandwidth needs fall to about 75Kbps. But you increase the delay! Tradeoff: bandwidth versus delay.

In the end, voice is entirely unlike other types of data carried over IP. Files require 100% of the bits to reach the other end and can tolerate delay. Voice is fine with a reasonable number of lost bits but cannot tolerate delay. Guess which the Internet was designed to favor? When you spec "bandwidth" for a VOIP connection, it's at best a proxy for delay-- high bandwidth pipes tend to have less delay. Bandwidth is less important than delay, and Service Level Agreements for VOIP need to explicitly spell out requirements for jitter and loss.

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