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Comment: Re:How does this qualify as "teleportation"? (Score 1) 333

by Keramos (#41248963) Attached to: Quantum Teleportation Sends Information 143 Kilometers

Two things to note:

First, they're not "teleporting" the photon. It's a quantum property (such as spin - which, also, by the way, doesn't have to do with the photon rotating in the way you'd think of, say, a ball spinning, but I digress) that is being "teleported" and applied to the target photon.

Second, when you send a fax, the "picture" (or the information to recreate it) is sent along the wires (or optic fibres, radio waves, etc.) through space from one location to the other. With entangled particles, the effect that alters the target particle's property doesn't travel through space. It just affects it directly. That's why it's instantaneous (as opposed to travelling at the speed of light or less, like your fax signal) and called teleportation. The downside is that this teleportation effect cannot convey information.

Comment: Many LAN printing apps are available (Score 1) 203

by Keramos (#38323746) Attached to: Ask Slashdot: Best Way To Print From an Android Tablet?
Many of the printer manufacturers have software that allows you to print to their printers if they are on a LAN your Android is connected to. I have a Samsung MFP and can print and scan quite easily using Samsung's mobile print app for example. Just match your printer manufacturer with the app and check it supports the model. What you can print depends on the printing app as it either implements an action or reads particular file types. The Samsung one reads from your picture gallery, google docs, web pages, facebook & twitter and various other format files in your documents directories (txt, pdf and I'm pretty sure some versions of office files). I find scanning often to be more straightforward than on my PC. Pretty sure there are apps for Brother, HP, Epson, Canon, etc. Their features & polish will probably vary. Just search for printer in the android market, eg https://market.android.com/search?q=print&so=1&c=apps Obviously if your printing is only over the LAN, it should be more secure than a "cloud" based method, and some of those apps charge per page printed IIRC.

Comment: Tablet-based device? (Score 1) 134

by Keramos (#38054552) Attached to: Ask Slashdot: Building an Assistive Reading Device?
What about an iPad or android tablet? They tend to have a "downward" facing camera and already have a screen. You could use it as a portable magnifier, for general use, as well as a reader. They have the capacity to do OCR on a book, and could present the text one word, or even one letter, at a time. I'm sure a book holder with a frame to support the tablet wouldn't be too hard to rig up - you could probably make it fold up and portable (fit inside a briefcase, say) with a little bit of thought.

Comment: Re:pegged connection == latency, who'd of thunk it (Score 4, Informative) 525

by Keramos (#34791772) Attached to: Bufferbloat — the Submarine That's Sinking the Net

There is no 'bufferbloat because RAM is getting cheaper'. What he is seeing is what happens when you want to saturate your link. ... ...you get either a buffered or a dropped packet.

Yes, and if a link is saturated, there should be packet drops, which TCP senses, then automatically throttles back to reduce the required bandwidth and avoid saturation. But what is happening, is that these huge buffers are holding packets that would otherwise be dropped, and so TCP doesn't get the feedback it needs to detect saturation. So it continues transmitting at full speed, believing it has uncongested pipes, which in turn continues to fill the buffers, and so on.

Because of the buffers, most of these packets are eventually getting through, but maybe in seconds instead of tens or low hundreds of milliseconds. Thus you're getting huge latency.

Jitter is caused by the buffers eventually filling or TCP timing out (registering packet loss), dropping the rate for a little bit, the buffers draining, then TCP upping the rate again as the buffers refill, hiding the saturation, until they're full again. Rinse and repeat.

It's related to the "bloat" of buffering (due to the increasing affordability of RAM and the "more of a good thing must be better than a little of a good thing - QED" mindset) because, if the size of the buffer is kept below a certain point related to the pipe bandwidth and number of traffic streams, it tends to act just as a temporary "buffer" against spikes in the traffic (the intention of buffering), and can't cause the scenario above, having insufficient capacity to overload the bandwidth just from buffer contents alone. Above this threshold, the latency issues and back-and-forth thrashing noted above occurs. The bigger the buffers, the worse the effect.

And it's not just a "well, keep your traffic below x mbit if you're on ADSL2" issue, because it happens anywhere a high capacity pipe interfaces with a low capacity or otherwise congested (of any capacity) pipe. This might be your ISP's backbone which is getting hit by several thousand people downloading the latest WOW patch simultaneously, causing your 300kbps Skype call to go to hell through latency and jitter. If the ISP's equipment had smaller buffers, the servers would be throttling back as packet loss occurred. You'd probably still be losing packets, but they'd be detected and re-transmitted pretty quickly and you possibly wouldn't notice the latency or have jitter.

What he is seeing is what happens when you want to saturate your link.

So, no, what you get with appropriate buffers is your TCP connection moderating itself to the appropriate link capacity and availability, and latency remaining approximately the same (relative to what you're seeing in bufferbloat, but worse than an uncongested link, obviously).

With bufferbloat, your bandwidth appears to remain about the same, but your latency balloons massively and you get jitter effects as above.

PC Games (Games)

DC Universe Online To Launch January 11th 49

Posted by Soulskill
from the dust-off-your-cape dept.
Sony Online Entertainment has announced that their long-awaited superhero MMO DC Universe Online will be launching on January 11th in the US and January 14th in the UK. The game will be available for Windows and the PlayStation 3. Massively recently wrote up their impressions from the beta test, and a preview at The Escapist said this of the combat: "Based on my early experiences, the action of DCUO is a lot of fun. You can lock onto targets, but there is no auto attack button. To take down enemies, you must click a button to punch or fire a ranged attack. The brawler-style action feels like a wham-bang comic book. Scenery is not just difficult terrain; picking up barrels and tossing them at your foes is sometimes necessary for tough encounters. Leveling up your skills unlocks combos, with varying effects that can interrupt enemies from pulling off that devastating fire breath or stunning punch. ... The only downside with such frenetic combat is that the keyboard and mouse interface isn't really conducive to all this action. It's hard to follow up nine short left clicks with a long right button click. While I was visiting SOE's offices, I was able to play with a PS3 controller, and this control scheme was preferable."
PC Games (Games)

Age of Conan, One Year On 119

Posted by Soulskill
from the still-alive dept.
One year after its rocky launch, Age of Conan has stabilized and seen a growth in its player base, reports FunCom. What's more, they say, is that players seem to be playing for longer periods of time as well. Game Director Craig Morrison said in his May letter that work on the next major update, 1.05, is nearing completion, and provided some more details about the new features. This is the same patch which, due to the sweeping stat and equipment changes, will allow players who have a character at level 50 or higher to create a brand new character already at level 50. Reader Kheldon points out a two-part interview with Morrison in which he discusses the laundry list of changes they've made in the past year to improve the game, as well as some broader thoughts about storytelling in the MMO genre. FunCom also released some early details yesterday on two new, free-to-play MMOs they're working on, one of which is browser-based and one of which is Java-based.

Comment: Nah, it's the martians arriving. (Score 4, Funny) 155

by Keramos (#26867435) Attached to: Collided Satellite Debris Coming Down?
My understanding was that the satellites were in an orbit high enough that the debris would float around for several thousand years before being caught by the atmosphere. I suppose a few bits might have had the energy to move closer in, but all in all it sounds more like the Martians have arrived. Might be a good idea to go make some bacteria bombs before they finish building those tripedal walkers.

If I have not seen so far it is because I stood in giant's footsteps.

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