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Hardware

Submission + - Qubits found in cheap, mass-produced semiconductor (extremetech.com)

Submitted by
MrSeb
MrSeb writes: "Physicists at UC Santa Barbara have discovered a quality of silicon carbide — a material commonly used in the manufacture of semiconductors — that can be used to perform quantum computing. Silicon carbide is a compound that has some 250 crystalline forms, but its 4H polytype has an imperfection that traps electrons. The spin of these electrons can then be manipulated and measured (addressed) with optical wavelengths. In short, silicon carbide is an array of solid-state, addressable qubits. The reason this is big news is because silicon carbide traps electrons at room temperature, and (so far) the only other material to exhibit this property is diamond. Unlike diamond, silicon carbide crystals can be grown at an industrial scale and relatively cheaply. Furthermore, the qubits in silicon carbide can be addressed using optical wavelengths already used in telecommunications."
Verizon

Submission + - Verizon Moving to Offer Premium QoS on Mobile (pcmag.com)

Submitted by Anonymous Coward
An anonymous reader writes: PC Mag attended an open-house event at Verizon's Application Innovation Center in San Francisco, where executives said Tuesday that "Verizon will publish an API that could allow consumers to "turbocharge" the network bandwidth their smartphone apps use for a small fee."

Verizon anticipates that a customer running an app on a smartphone will have the option to dynamically snatch more bandwidth for that app, if network congestion slows it down, said Hugh Fletcher, associate director for technology in Verizon's Product Development and Technology team. The app, however, must be running what Verizon referred to as the network optimization API it is currently developing, and hopes to publish by the third quarter of 2012.

This comes after Verizon's earlier claims that "Verizon is fully committed to an open Internet."

Comment iRedMail+SOGo+Funambol (Score 1) 554

by KazW (#37015800) Attached to: Ask Slashdot: Self-Hosted Gmail Alternatives?
I use iRedMail+SOGo+Funambol... iRedMail is a CentOS based email server that supports domain keys, multiple domains, spam assassin, sieve filtering, mailbox quotas, email aliases, mailing lists and an LDAP/MySQL hybrid backend (and many more features). SOGo is a very nice groupware suite with a calendar and can be hooked up to Thunderbird with Lightening for a desktop UI, SOGo can also pull from POP/IMAP accounts on other servers. You can also link SOGo to iRedMail's sieve server to make email filtering rules from the web UI, SOGo also supports multiple identities for one user and multiple domains. Funambol connects to SOGo and syncs everything to your iOS/Android/Windows Mobile devices, including email, contacts and calendar (you can also save photos and other media/stuff to Funambol, but I haven't used it). All of these services are easy to wrap up in SSL when using Apache as a proxy (SOGo and Funambol are their own HTTP servers, but are limiting if you want to run everything on one domain with SSL). This setup also works great on a VPS.

My only complaint is that iRedMail's use of LDAP isn't great and it can be a pain to configure other services like Samba, NFS/NIS and OpenVPN to use it's LDAP, but it's doable. iRedMail also has a nice web UI for basic operations like adding a domain and users, and there is a more advance admin UI available ($200/year), but if you can use phpLDAPadmin and Google, you don't need it.

As for security concerns, iRedMail is already setup to be secure as far as not being an open relay. As for securing the web UI, modify your Apache config and only let certain services use https (public), and set the admin stuff to use http (or https if you have 2 NICs) via only the local network.

The last step would be to get a cheap little VPS somewhere and set it up to be a backup MX.
Idle

Submission + - Keys Can Be Copied From Pictures Taken 200ft Away (singularityhub.com) 1

Submitted by
kkleiner
kkleiner writes: "A group of computer scientists at UC San Diego have developed software, called Sneakey, that can copy keys using digital images taken from large distances, and from almost any angle. In one demonstration they duplicated a key using an image captured on a cell phone camera. In another demonstration, with the help of a telephoto lens they were able to duplicate keys sitting on a café table almost 200 feet away. Incredibly, all of the copies worked when tested out on the relevant locks."
Wireless Networking

Submission + - What's killing your Wi-Fi? (pcpro.co.uk)

Submitted by
Barence
Barence writes: "PC Pro has taken an in-depth look at Wi-Fi and the factors that can cause connections to crumble. It dispels some common myths about Wi-Fi problems — such as that neighbouring Wi-Fi hotspots are the most common cause of problems, instead of other RF interference from devices such as analogue video senders, microwave ovens and even fish tanks. The feature also highlights free and paid-for tools that can diagnose Wi-Fi issues, such as inSSIDer and Heatmapper, the latter of which maps provides a heatmap of Wi-Fi hotspots in your home or office."
Programming

Submission + - Tiny cores are here, and they change programming (futurechips.org) 3

Submitted by Anonymous Coward
An anonymous reader writes: Intel is returning to in-order cores after two decades with Atom and Knights. ARM is already building in-order cores for iPhones, iPads, and Androids. IBM has switched to in-order cores after building generations of out-of-order cores. This indicates a clear trend that in-order cores are back in the mainstream. Highlighting the performance characteristics of in-order and out-of-order cores, Dr. Aater Suleman's article explains why programming for in-order cores is very different from programming for the now-traditional out-of-order cores. Thus, this new trend requires a change in compilers, tools, and programming techniques. Compilers need to get better at removing useless code and instruction scheduling. Programmers need to weigh new trade-offs and perform classic optimizations that have been forgotten. I liked this article particularly for the very simple code examples and a simple explanation of in-order and out-of-order differences. The message is clear: programmers and compilers need to understand in-order cores and target their code better.
AI

Submission + - Watson Wins (bloomberg.com) 3

Submitted by NicknamesAreStupid
NicknamesAreStupid writes: The word is in, Watson beats the two best Jeopardy players. Sure, it cost IBM four years and millions of dollars and requires a room full of hardware. In thirty years it will all fit in your pocket and cost $19.99. Resistance is futile; you will be trivialized.
Earth

Submission + - Researchers: 100% Green Energy Possible By 2050 (greencarreports.com)

Submitted by thecarchik
thecarchik writes: Researchers from Stanford University and the University of California-Davis published their analysis in the journal Energy Policy. The main challenges, say the authors, will be summoning the global will to make the conversion.

There are no technological or economic barriers to converting the entire world to clean, renewable energy sources, said author Mark Jacobson, a Stanford professor, saying it is only a question of "whether we have the societal and political will."

During this decade, the two "fuels of the future" will be electricity and gasoline. Beyond that, we can't project.
Java

Submission + - Sun Java is the most vulnerable plug-in (net-security.org) 1

Submitted by dinscott
dinscott writes: Wondering how secure your browser is? Research show that browsers and plug-ins are frequently outdated and easily attackable. To make things worse, malware authors adapt quickly and most of their new attacks are against browser plug-ins.

The problem is that people might remember to update the browser, but forget to do the same with the plug-ins — and they are not typically updated by the browser itself. And while everybody knows about the hackers' predilection for targeting Adobe Flash, data shows that Sun Java is by far the most vulnerable plug-in installed in browsers.
Linux

Submission + - 6 of the Best Free Linux Point-of-Sale Software (linuxlinks.com)

Submitted by Anonymous Coward
An anonymous reader writes: Point-of sale (POS) is the location where a transaction takes place. It also refers to the immediate capture of transactions and customer payment information when goods and services are purchased. This data can be obtained using many different devices such as a computer, cash register, barcode scanner, PIN pads, and magnetic card readers.

A POS system consists of a number of different components, including computer hardware, a computer operating system, checkout hardware, and checkout software. A key part is the POS software. The purpose of this article is to identify Linux software that forms part of the checkout system. With the current economic climate, open source POS software has the obvious advantage of helping a business to lower costs.

To provide an insight into the open source software that is available, we have compiled a list of 6 of our favorite Point-of-Sale software. Hopefully, there will be something of interest here for anyone who needs to track sales and inventory as they occur.
Books

Submission + - PostgreSQL 9.0 High Performance (packtpub.com)

Submitted by eggyknap
eggyknap writes: Thanks in large part to the oft-hyped "NoSQL" movement, database performance has received a great deal of press in the past few years. Organizations large and small have replaced their traditional relational database applications with new technologies like key-value stores, document databases, and other systems, with great fanfare and often great success. But replacing a database system with something radically different is a difficult undertaking, and these new database systems achieve their impressive results principally because they abandon some of the guarantees traditional database systems have always provided.

For those of us who need improved performance but don't have the luxury of redesigning our systems, and even more for those of us who still need traditional transactions, data integrity, and SQL, there is an option. Greg Smith's book, "PostgreSQL 9.0 High Performance" takes the reader step-by-step through the process of building an efficient and responsive database using "the world's most advanced open source database".

Greg Smith has been a major contributor to PostgreSQL for many years, with work focusing particularly on performance. In "PostgreSQL 9.0 High Performance", Smith starts at the lowest level and works through a complete system, sharing his experience with systematic benchmarking and detailed performance improvement at each step. Despite the title, the material applies not only to PostgreSQL's still fairly new 9.0 release, but to previous releases as well. After introducing PostgreSQL, briefly discussing its history, strengths and weaknesses, and basic management, the book dives into a detailed discussion of hardware and benchmarking, and doesn't come out for 400 pages.

Databases vary, of course, but in general they depend on three main hardware factors: CPU, memory, and disks. Smith discusses each in turn, and in substantial detail, as demonstrated in a sample chapter available from the publisher, Packt Publishing. After describing the various features and important considerations of each aspect of a database server's hardware, the book introduces and demonstrates powerful and widely available tools for testing and benchmarking. This section in particular should apply easily not only to administrators of PostgreSQL databases, but users of other databases, or indeed other applications as well, where CPU, memory, or disk performance is a critical factor. Did you know, for instance, the difference between "write-through" and "write-back" caching in disk, and why it matters to a database? Or did you know that disks perform better depending on which part of the physical platter they're reading? How does memory performance compare between various common CPUs through the evolution of their different architectures?

At every step, Smith encourages small changes and strict testing, to ensure optimum results from your performance efforts. His discussion includes methods for reducing and correcting variability, and sticks to easily obtained and interpreted tools, whose output is widely understood and for which support is readily available. The underlying philosophy has correctly been described as "measure, don't guess," a welcome relief in a world where system administrators often make changes based on a hunch or institutional mythology.

Database administrators often limit their tools to little more than building new indexes and rewriting queries, so it's surprising to note that those topics don't make their appearance until chapters 9 and 10 respectively, halfway through the book. That said, they receive the same detailed attention given earlier to database hardware, and later on to monitoring tools and replication. Smith thoroughly explains each of the operations that may appear in PostgreSQL's often overwhelming query plans, describes each index type and its variations, and goes deeply into how the query planner decides on the best way to execute a query.

Other chapters cover such topics as file systems, configuration options suitable for various scenarios, partitioning, and common pitfalls, each in depth. In fact, the whole book is extremely detailed. Although the tools introduced for benchmarking, monitoring, and the like are well described and their use nicely demonstrated, this is not a book a PostgreSQL beginner would use to get started. Smith's writing style is clear and blessedly free of errors and confusion, as is easily seen by his many posts on PostgreSQL mailing lists throughout the years, but it is deeply detailed, and the uninitiated could quickly get lost.

This is also a very long book, and although not built strictly as a reference manual, it's probably best treated as one, after an initial thorough reading. It covers each topic in such detail that each must be absorbed before further reading can be beneficial. Figures and other non-textual interruptions are, unfortunately, almost nowhere to be found, so despite the author's clear and easy style, it can be a tiring read.

It is, however, one of the clearest, most thorough, and best presented descriptions of the full depth of PostgreSQL currently available, and doubtless has something to teach any frequent user of a PostgreSQL database. Those planning a new database will welcome the straightforward and comprehensive presentation of hardware-level details that are difficult or impossible to change after a system goes into production; administrators will benefit from its discussion of configuration options and applicable tools; and users and developers will embrace its comprehensive description of query planning and optimization. "PostgreSQL 9.0 High Performance" will be a valuable tool for all PostgreSQL users interested in getting the most from their database.
Image

Sharks Seen Swimming Down Australian Streets 210

Posted by samzenpus from the we're-going-to-need-a-bigger-sidewalk dept.
As if the flood waters weren't bad enough for the people of Queensland, it now appears that there are sharks swimming in the streets. Two bull sharks were spotted swimming past a McDonald’s in the city of Goodna, Butcher Steve Bateman saw another making its way past his shop on Williams street. Ipswich councillor for the Goodna region Paul Tully said: "It would have swam several kilometres in from the river, across Evan Marginson Park and the motorway. It’s definitely a first for Goodna, to have a shark in the main street."
Software

Graphic Map of Linux-2.6.36 25

Posted by timothy from the under-the-hood dept.
conan.sh writes "The Interactive map of Linux Kernel was expanded and updated to the recent kernel linux-2.6.36. Now the map contains more than four hundred important source items (functions and structures) with links to source code and documentation."
Databases

Cassandra 0.7 Can Pack 2 Billion Columns Into a Row 235

Posted by timothy from the but-only-if-they're-really-thin dept.
angry tapir writes "The cadre of volunteer developers behind the Cassandra distributed database have released the latest version of their open source software, able to hold up to 2 billion columns per row. The newly installed Large Row Support feature of Cassandra version 0.7 allows the database to hold up to 2 billion columns per row. Previous versions had no set upper limit, though the maximum amount of material that could be held in a single row was approximately 2GB. This upper limit has been eliminated."

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