Ironically, WDS (when compatible) is generally considered the superior solution. Without getting into the nitty-gritty, it’s just a cleaner, more efficient solution, with fewer idiosyncrasies than universal bridging. But what always kills WDS is the incompatibilities.
via WDS vs Repeater – Wireless Network – Wireless Networking.
The task of monitoring networks requires reading all the data packets as they cross the network, which “requires a lot of data parallelism,” Wenji said.
Wenji has built a prototype at Fermilab to demonstrate the feasibility of a GPU-based network monitor, using a Nvidia M2070 GPU and an off-the-shelf NIC (network interface card) to capture network traffic. The system could easily be expanded with additional GPUs, he said.
via Super Computing 13: GPUs would make terrific network monitors – Network World.
In practical terms, this means that Man-In-the-Middle BGP route hijacking has now moved from a theoretical concern to something that happens fairly regularly, and the potential for traffic interception is very real. Everyone on the Internet — certainly the largest global carriers, certainly any bank or credit card processing company or government agency — should now be monitoring the global routing of their advertised IP prefixes.
This kind of attack should not happen. You cannot carry out this kind of hijacking without leaving permanent, visible footprints in global routing that point right back to the point of interception. We believe that people are still attempting this because they believe (correctly, in most cases) that nobody is looking.
via The New Threat: Targeted Internet Traffic Misdirection – Renesys.
I found this paper very useful.
ABSTRACT
Wireless sensor networks promise fine-grain monitoring in a wide variety of environments. Many of these environments (e.g., indoor environments or habitats) can be harsh for wireless communication. From a networking perspective, the most basic aspect of wireless communication is the packet delivery performance: the spatio-temporal characteristics of packet loss, and its environmental dependence.
These factors will deeply impact the performance of data acquisition from these networks.
In this paper, we report on a systematic medium-scale (up to sixty nodes) measurement of packet delivery in three different environments: an indoor office building, a habitat with moderate foliage, and an open parking lot. Our findings have interesting implications for the design and evaluation of routing and medium-access protocols for sensor networks.
via Understanding Packet Delivery Performance In Dense Wireless Sensor Networks
Since the Model S went into production last year, there have been more than a quarter million gasoline car fires in the United States alone, resulting in over 400 deaths and approximately 1,200 serious injuries (extrapolating 2012 NFPA data). However, the three Model S fires, which only occurred after very high-speed collisions and caused no serious injuries or deaths, received more national headlines than all 250,000+ gasoline fires combined. The media coverage of Model S fires vs. gasoline car fires is disproportionate by several orders of magnitude, despite the latter actually being far more deadly.
Reading the headlines, it is therefore easy to assume that the Tesla Model S and perhaps electric cars in general have a greater propensity to catch fire than gasoline cars when nothing could be further from the truth.
To understand how current flows in a material you first have to understand electrons behave in a material. The key feature of solid state physics is that many materials are crystals. This means that the atoms are spaced periodically. As you mention, band structures are the way that we summarize the effect of this periodic potential. Basically, a band structure just relates an electrons momentum p=mv=hbar k to its energy. The momentum can be positive or negative, the sign only denotes direction. In free space this is very boring, Energy=m v2 /2 = p2 /2m=hbar k2 /2m. When you throw in a periodic potential, this becomes modified and results in bands. Actually calculating band structures is quite difficult. The key idea is that there are ranges of energy where the electron can live and ranges of energy where the electron cannot live.
via What does current look like on a quantum level? : askscience.
In June, Snapchat raised $60 million from investors including Institutional Venture Partners; that round valued the company at $800 million.
Three months later, Snapchat said its usage had nearly doubled, to 350 million messages or “snaps” per day, up from 200 million in June.
via Snapchat Spurned $3 Billion Acquisition Offer from Facebook – Digits – WSJ.
But Jones didn’t invent SSL; nor did he invent RC4, an algorithm invented in 1987, two years before the filing date of the Jones patent.
Whatever his invention is, it came before the World Wide Web, which was made available to everyone in 1993. Jones filed for his patent in 1989, and it uses some distinctively pre-Web vocabulary; describing encryption via modems and phone lines.
via Newegg hurtles toward Texas showdown with famed “patent troll” | Ars Technica.
By claiming such common encryption, the TQP patent is essentially a “we-own-the-Internet” patent. Spangenberg declined to speak to Ars for this story, but in an August interview he said the TQP licensing campaign has reaped around $40 million in revenue.
If you want hydrogen to power an engine or a fuel cell, it’s far cheaper to get it from natural gas than to make it by splitting water. Solar power, however, could compete with natural gas as a way to make hydrogen if the solar process were somewhere between 15 and 25 percent efficient, says the U.S. Department of Energy. While that’s more than twice as efficient as current approaches, researchers at Stanford University have recently developed materials that could make it possible to hit that goal. The work is described in the journal Science.
via Artificial Photosynthesis Made Practical | MIT Technology Review.
The FCC’s new chairman, Tom Wheeler, is taking the wireless operators to task over their cellphone unlocking policies in his first month on the job. He has told them to get moving on addressing consumers’ rights to unlock their phones once their contracts are fulfilled — or they will face regulation.