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• eSTEP Newsletter November 2012

  - by mseika

  Dear Partners,We would like to inform you that the November '12 issue of our Newsletter is now available.The issue contains information to the following topics: News from CorpOracle Celebrates 25 Years of SPARC Innovation; IDC White Papers Finds Growing Customer Comfort with Oracle Solaris Operating System; Oracle Buys Instantis; Pillar Axiom OpenWorld Highlights; Announcement Oracle Solaris 11.1 Availability (data sheet, new features, FAQ's, corporate pages, internal blog, download links, Oracle shop); Announcing StorageTek VSM 6; Announcement Oracle Solaris Cluster 4.1 Availability (new features, FAQ's, cluster corp page, download site, shop for media); Announcement: Oracle Database Appliance 2.4 patch update becomes available Technical SectionOracle White papers on SPARC SuperCluster; Understanding Parallel Execution; With LTFS, Tape is Gaining Storage Ground with additional link to How to Create Oracle Solaris 11 Zones with Oracle Enterprise Manager Ops Center; Provisioning Capabilities of Oracle Enterprise Ops Center Manager 12c; Maximizing your SPARC T4 Oracle Solaris Application Performance with the following articles: SPARC T4 Servers Set World Record on Siebel CRM 8.1.1.4 Benchmark, SPARC T4-Based Highly Scalable Solutions Posts New World Record on SPECjEnterprise2010 Benchmark, SPARC T4 Server Delivers Outstanding Performance on Oracle Business Intelligence Enterprise Edition 11g; Oracle SUN ZFS Storage Appliance Reference Architecture for VMware vSphere4; Why 4K? - George Wilson's ZFS Day Talk; Pillar Axiom 600 with connected subjects: Oracle Introduces Pillar Axiom Release 5 Storage System Software, Driving down the high cost of Storage, This Provisioning with Pilar Axiom 600, Pillar Axiom 600- System overview and architecture; Migrate to Oracle;s SPARC Systems; Top 5 Reasons to Migrate to Oracle's SPARC Systems Learning & EventsRecently delivered Techcasts: Learning Paths; Oracle Database 11g: Database Administration (New) - Learning Path; Webcast: Drill Down on Disaster Recovery; What are Oracle Users Doing to Improve Availability and Disaster Recovery; SAP NetWeaver and Oracle Exadata Database Machine ReferencesARTstor Selects Oracle’s Sun ZFS Storage 7420 Appliances To Support Rapidly Growing Digital Image Library, Scottish Widows Cuts Sales Administration 20%, Reduces Time to Prepare Reports by 75%, and Achieves Return on Investment in First Year, Oracle's CRM Cloud Service Powers Innovation: Applications on Demand; Technology on Demand, How toHow to Migrate Your Data to Oracle Solaris 11 Using Shadow Migration; Using svcbundle to Create SMF Manifests and Profiles in Oracle Solaris 11; How to prepare a Sun ZFS Storage Appliance to Serve as a Storage Devise with Oracle Enterprise Manager Ops Center 12c; Command Summary: Basic Operations with the Image Packaging System In Oracle Solaris 11; How to Update to Oracle Solaris 11.1 Using the Image Packaging System, How to Migrate Oracle Database from Oracle Solaris 8 to Oracle Solaris 11; Setting Up, Configuring, and Using an Oracle WebLogic Server Cluster; Ease the Chaos with Automated Patching: Oracle Enterprise Manager Cloud Control 12c; Book excerpt: Oracle Exalogic Elastic Cloud HandbookYou find the Newsletter on our portal under eSTEP News ---> Latest Newsletter. You will need to provide your email address and the pin below to get access. Link to the portal is shown below.URL: http://launch.oracle.com/PIN: eSTEP_2011Previous published Newsletters can be found under the Archived Newsletters section and more useful information under the Events, Download and Links tab. Feel free to explore and any feedback is appreciated to help us improve the service and information we deliver.Thanks and best regards,Partner HW Enablement EMEA

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• Faster Trip to Innovation with Simplified Data Integration: Sabre Holdings Case Study

  - by Tanu Sood

  Normal 0 false false false EN-US X-NONE X-NONE /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin-top:0in; mso-para-margin-right:0in; mso-para-margin-bottom:10.0pt; mso-para-margin-left:0in; line-height:115%; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} Author: Irem Radzik, Director of Product Marketing, Data Integration, Oracle In today’s fast-paced, competitive environment, IT teams are under pressure to deliver technology solutions for many critical business initiatives as fast as possible. When the focus is on speed, it can be easy to continue to use old style, point-to-point custom scripts that grow organically to the point where they are unmanageable and too costly to maintain. As data volumes, data sources, and end users grow, uncoordinated data integration efforts create significant inefficiencies for both IT and business users. In addition to losing IT productivity due to maintaining spaghetti architecture, data integrity becomes a concern as well. Errors caused by inconsistent, data and manual data entry can prove very costly for companies and disrupt business activities. Many industry leaders recognize now that data should be moved in an automated and reliable manner across all platforms to have one version of the truth. By simplifying their data integration architecture and standardizing on a centralized approach, IT teams now accelerate time to market. Especially, using a centralized, shared-service approach brings agility, increases IT productivity, and frees up resources for innovation. One such industry leader that simplified its data integration architecture is Sabre Holdings. Sabre Holdings provides distribution and technology solutions for the travel industry, and is a winner of Oracle Excellence Awards for Fusion Middleware in 2011 in the data integration category. I had the pleasure to host Sabre Holdings on a public webcast and discuss their data integration best practices for data warehousing. In this webcast Sabre’s Amjad Saeed, presented how the company reduced complexity by consolidating systems and standardizing development on Oracle Data Integrator and Oracle GoldenGate for its global data warehouse development team. With Oracle’s complete real-time data integration solution, Sabre also streamlined support and maintenance operations, achieved real-time view in the execution of the integration processes, and can manage the data warehouse and business intelligence solution performance on demand. By reducing complexity and leveraging timely market insights, the company was able to decrease time to market by 40%. You can now listen to the webcast on demand: Sabre Holdings Case Study: Accelerating Innovation using Oracle Data Integration I invite you to hear directly from Sabre how to use advanced data integration capabilities to enable accelerated innovation. To learn more about Oracle’s data integration offering you can download our free resources.

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• Framework for Everything - Where to begin? [Longer post]

  - by SquaredSoft

  Back story of this question, feel free to skip down for the specific question Hello, I've been very interested in the idea of abstract programming the last few years. I've made about 30 attempts at creating a piece of software that is capable of almost anything you throw at it. I've undertook some attempts at this that have taken upwards of a year, while getting close, never releasing it beyond my compiler. This has been something I've always tried wrapping my head around, and something is always missing. With the title, I'm sure you're assuming, "Yes of course you noob! You can't account for everything!" To which I have to reply, "Why not?" To give you some background into what I'm talking about, this all started with doing maybe a shade of gray hat SEO software. I found myself constantly having to create similar, but slightly different sets of code. I've gone through as many iterations of way to communicate on http as the universe has particles. "How many times am I going to have to write this multi-threaded class?" is something I found myself asking a lot. Sure, I could create a class library, and just work with that, but I always felt I could optimize what I had, which often was a large undertaking and typically involved frequent use of the CRTL+A keyboard shortcut, mixed with the delete button. It dawned on me that it was time to invest in a plugin system. This would allow me to simply add snippets of code. as time went on, and I could subversion stuff out, and distribute small chunks of code, rather than something that encompasses only a specific function or design. This comes with its own complexity, of course, and by the time I had finished the software scope for this addition, it hit me that I would want to add to everything in the software, not just a new http method, or automation code for a specific website. Great, we're getting more abstract. However, the software that I have in my mind comes down to a quite a few questions regarding its execution. I have to have some parameters to what I am going to do. After writing what the perfect software would do in my mind, I came up with this as a list of requirements: Should be able to use networking A "Macro" or "Expression system" which would allow people to do something like : =First(=ParseToList(=GetUrl("http://www.google.com?q=helloworld!"), Template.Google)) Multithreaded Able to add UI elements through some type of XML -- People can make their own addons etc. Can use third party API through the plugins, such as Microsoft CRM, Exchange, etc. This would allow the software to essentially be used for everything. Really, any task you wish to automate, in a simple way. Making the UI was as also extremely hard. How do you do all of this? Its very difficult. So my question: With so many attempts at this, I'm out of ideas how to successfully complete this. I have a very specific idea in my mind, but I keep failing to execute it. I'm a self taught programmer. I've been doing it for years, and work professionally in it, but I've never encountered something that would be as complex and in-depth as a system which essentially does everything. Where would you start? What are the best practices for design? How can I avoid constantly having to go back and optimize my software. What can I do to generalize this and draw everything out to completion. These are things I struggle with. P.s., I'm using c# as my main language. I feel like in this example, I might be hitting the outer limit of the language, although, I don't know if that is the case, or if I'm just a bad programmer. Thanks for your time.

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• 4 Key Ingredients for the Cloud

  - by Kellsey Ruppel

  It's a short week here with the US Thanksgiving Holiday. So, before we put on our stretch pants and get ready to belly up to the dinner table for turkey, stuffing and mashed potatoes, let's spend a little time this week talking about the Cloud (kind of like the feathery whipped goodness that tops the infamous Thanksgiving pumpkin pie!) But before we dive into the Cloud, let's do a side by side comparison of the key ingredients for each. Cloud Whipped Cream  Application Integration  1 cup heavy cream  Security  1/4 cup sugar  Virtual I/O  1 teaspoon vanilla  Storage  Chilled Bowl It’s no secret that millions of people are connected to the Internet. And it also probably doesn’t come as a surprise that a lot of those people are connected on social networking sites.  Social networks have become an excellent platform for sharing and communication that reflects real world relationships and they play a major part in the everyday lives of many people. Facebook, Twitter, Pinterest, LinkedIn, Google+ and hundreds of others have transformed the way we interact and communicate with one another.Social networks are becoming more than just an online gathering of friends. They are becoming a destination for ideation, e-commerce, and marketing. But it doesn’t just stop there. Some organizations are utilizing social networks internally, integrated with their business applications and processes and the possibility of social media and cloud integration is compelling. Forrester alone estimates enterprise cloud computing to grow to over $240 billion by 2020. It’s hard to find any current IT project today that is NOT considering cloud-based deployments. Security and quality of service concerns are no longer at the forefront; rather, it’s about focusing on the right mix of capabilities for the business. Cloud vs. On-Premise? Policies & governance models? Social in the cloud? Cloud’s increasing sophistication, security in applications, mobility, transaction processing and social capabilities make it an attractive way to manage information. And Oracle offers all of this through the Oracle Cloud and Oracle Social Network. Oracle Social Network is a secure private network that provides a broad range of social tools designed to capture and preserve information flowing between people, enterprise applications, and business processes. By connecting you with your most critical applications, Oracle Social Network provides contextual, real-time communication within and across enterprises. With Oracle Social Network, you and your teams have the tools you need to collaborate quickly and efficiently, while leveraging the organization’s collective expertise to make informed decisions and drive business forward. Oracle Social Network is available as part of a portfolio of application and platform services within the Oracle Cloud. Oracle Cloud offers self-service business applications delivered on an integrated development and deployment platform with tools to rapidly extend and create new services. Oracle Social Network is pre-integrated with the Fusion CRM Cloud Service and the Fusion HCM Cloud Service within the Oracle Cloud. If you are looking for something to watch as you veg on the couch in a post-turkey dinner hangover, you might consider watching these how-to videos! And yes, it is perfectly ok to have that 2nd piece of pie

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• Representing Mauritius in the 2013 Bench Games

  Only by chance I came across an interesting option for professionals and enthusiasts in IT, and quite honestly I can't even remember where I caught attention of Brainbench and their 2013 Bench Games event. But having access to 600+ free exams in a friendly international intellectual competition doesn't happen to be available every day. So, it was actually a no-brainer to sign up and browse through the various categories. Most interestingly, Brainbench is not only IT-related. They offer a vast variety of fields in their Test Center, like Languages and Communication, Office Skills, Management, Aptitude, etc., and it can be a little bit messy about how things are organised. Anyway, while browsing through their test offers I added a couple of exams to 'My Plan' which I would give a shot afterwards. Self-assessments Actually, I took the tests based on two major aspects: 'Fun Factor' and 'How good would I be in general'... Usually, you have to pay for any kind of exams and given this unique chance by Brainbench to simply train this kind of tests was already worth the time. Frankly speaking, the tests are very close to the ones you would be asked to do at Prometric or Pearson Vue, ie. Microsoft exams, etc. Go through a set of multiple choice questions in a given time frame. Most of the tests I did during the Bench Games were based on 40 questions, each with a maximum of 3 minutes to answer. Ergo, one test in maximum 2 hours - that sounds feasible, doesn't it? The Measure of Achievement While the 2013 Bench Games are considered a worldwide friendly competition of knowledge I was really eager to get other Mauritians attracted. Using various social media networks and community activities it all looked quite well at the beginning. Mauritius was listed on rank #19 of Most Certified Citizens and rank #10 of Most Master Level Certified Nation - not bad, not bad... Until... the next update of the Bench Games Leaderboard. The downwards trend seemed to be unstoppable and I couldn't understand why my results didn't show up on the Individual Leader Board. First of all, I passed exams that were not even listed and second, I had better results on some exams listed. After some further information from the organiser it turned out that my test transcript wasn't available to the public. Only then results are considered and counted in the competition. During that time, I actually managed to hold 3 test results on the Individuals... Other participants were merciless, eh, more successful than me, produced better test results than I did. But still I managed to stay on the final score board: An 'exotic' combination of exam, test result, country and person itself Representing Mauritius and the Visual FoxPro community in that fun event. And although I mainly develop in Visual FoxPro 9.0 SP2 and C# using .NET Framework from 2.0 to 4.5 since a couple of years I still managed to pass on Master Level. Hm, actually my Microsoft Certified Programmer (MCP) exams are dated back in June 2004 - more than 9 years ago... Look who got lucky... As described above I did a couple of exams as time allowed and without any preparations, but still I received the following mail notification: "Thank you for recently participating in our Bench Games event.  We wanted to inform you that you obtained a top score on our test(s) during this event, and as a result, will receive a free annual Brainbench subscription.  Your annual subscription will give you access to all our tests just like Bench Games, but for an entire year plus additional benefits!" -- Leader Board Notification from Brainbench Even fun activities get rewarded sometimes. Thanks to @Brainbench_com for the free annual subscription based on my passed 2013 Bench Games Master Level exam. It would be interesting to know about the total figures, especially to see how many citizens of Mauritius took part in this year's Bench Games. Anyway, I'm looking forward to be able to participate in other challenges like this in the future.

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• How do you deal with poor management [closed]

  - by Sybiam

  I come from a company where during a project, we saw the client 3 time during the whole project. We were never informed when did the client came in office in order to discuss with him about his requirements. I did setup redmine and told them that if they have any request they can post an issue there. But they never really used redmine to publish anything. They would instead: harass a team member on the phone at any time of the day or night hand us over sheets of paper with new requests or changes hand us over new design (graphical) They requested how much time it would take us to finish the project, I gave them a date and a week to test everything and deployment. I calculated that time taking into account the current features we had to do. And then blamed us that our deadline was wrong and that we lied. But the truth is that one week before that deadline they added a couple of monster feature from nowhere and that week were we were supposed to test and deploy, my friends spent all day in the office changing all little things. After that project, my friend got some kind of depression and got scared everytime his phone rang. They kind of used him as a communication proxy. After that project of hell, (every body got pissed off on that project) as far as I know the designer who was working with us left work after that project and she had some kind of issue too with managers. My team also started looking for work somewhere else. At first I tried to get things straight with management, I tried to make a meeting to discuss about the communication issues and so on.. What really pissed me off and made me leave that job for good is the following. Me: "We have to discuss about what went wrong on the last project. It's quite important" Him: "Lets talk about it in a week or two. Just make a list of all the things you did wrong" Me: "We already have a new project and we want to prevent what happened on the last project to happen again" Him: "Just do it and well have our meeting in a week, make a list of all the thing you did wrong." It kind of ended there then he organized a meeting at a moment I wasn't unable to come. My friend discussed with him and tried to explained him that we really had to discuss about organization issue on how to manage a project. And his answer was pretty much: "During the meeting I don't want to ear how you want to us to manage a project but I want to know what you guys did wrong" After that I felt it wasn't even worth it discussing anything since they weren't even ready listening to us. Found a new job and I'm pretty happy with my choice. I'd like to know how you'd handle such situation. Is there anything to do to solve communication problem? After that project my friend got a depression and some other employee had their down too as far as I know. I wonder what else we can do other than leave these place as soon as possible. Feel sad for the people that are still there and get screamed at just because they need money in order to eat and finding an other job like that isn't that easy. note I died a little when our boss asked us to make a list of things we (programmers) did wrong. This is probably the stupidest request I ever got. If everybody thinks they did everything right, it doesn't mean that there is no problems. Individual problem are rarely the big issue. Colleagues help each others and solve theses issues to prevent problems.

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• The best computer ever

  - by Jeff

  (This is a repost from my personal blog… wow… I need to write more technical stuff!) About three years and three months ago, I bought a 17" MacBook Pro, and it turned out to be the best computer I've ever owned. You might think that every computer with better specs is automatically better than the last, but that hasn't been my experience. My first one was a Sony, back in the Pentium III days, and it cost an astonishing $2,500. That was even more ridiculous in 1999 dollars. It had a dial-up modem, and a CD-ROM, built-in! It may have even played DVD's. A few years later I bought an HP, and it ended up being a pile of shit. The power connector inside came loose from the board, and on occasion would even short. In 2005, I bought a Dell, and it wasn't bad. It had a really high resolution screen (complete with dead pixels, a problem in those days), and it was the first laptop I felt I could do real work on. When 2006 rolled around, Apple started making computers with Intel CPU's, and I bought the very first one the week it came out. I used Boot Camp to run Windows. I still have it in its box somewhere, and I used it for three years. The current 17" was new in 2009. The goodness was largely rooted in having a big screen with lots of dots. This computer has been the source of hundreds of blog posts, tens of thousands of lines of code, video and photo editing, and of course, a whole lot of Web surfing. It connected to corpnet at Microsoft, WiFi in Hawaii and has presented many a deck. It has traveled with me tens of thousands of miles. Last year, I put a solid state drive in it, and it was like getting a new computer. I can boot up a Windows 7 VM in about 19 seconds. Having 8 gigs of RAM has always been fantastic. Everything about it has been fast and fun. When new, the battery (when not using VM's) could get as much as 10 hours. I can still do 7 without much trouble. After 460 charge cycles, the battery health is still between 85 and 90%. The only real negative has been the size and weight. It's only an inch thick, but naturally it's pretty big with a 17" screen. You don't get battery life like that without a huge battery, either, so it's heavy. It was never a deal breaker, but sometimes a long haul across a large airport, you know you're carrying it. Today, Apple announced a new, thinner and lighter 15" laptop, with twice the RAM and CPU cores, and four times the screen resolution. It basically handles my size and weight issues while retaining the resolution, and it still costs less than my 17" did. So I ordered one. Three years is an excellent run, but I kind of budgeted for a new workhorse this year anyway. So if you're interested in a 17" MacBook Pro with a Core 2 Duo 2.66 GHz CPU, 8 gigs of RAM and a 320 gig hard drive (sorry, I'm keeping the SSD), I have one to sell. They've apparently discontinued the 17", which is going to piss off the video community. It's in excellent condition, with a few minor scratches, but I take care of my stuff.

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• Patterns for a tree of persistent data with multiple storage options?

  - by Robin Winslow

  I have a real-world problem which I'll try to abstract into an illustrative example. So imagine I have data objects in a tree, where parent objects can access children, and children can access parents: // Interfaces interface IParent<TChild> { List<TChild> Children; } interface IChild<TParent> { TParent Parent; } // Classes class Top : IParent<Middle> {} class Middle : IParent<Bottom>, IChild<Top> {} class Bottom : IChild<Middle> {} // Usage var top = new Top(); var middles = top.Children; // List<Middle> foreach (var middle in middles) { var bottoms = middle.Children; // List<Bottom> foreach (var bottom in bottoms) { var middle = bottom.Parent; // Access the parent var top = middle.Parent; // Access the grandparent } } All three data objects have properties that are persisted in two data stores (e.g. a database and a web service), and they need to reflect and synchronise with the stores. Some objects only request from the web service, some only write to it. Data Mapper My favourite pattern for data access is Data Mapper, because it completely separates the data objects themselves from the communication with the data store: class TopMapper { public Top FetchById(int id) { var top = new Top(DataStore.TopDataById(id)); top.Children = MiddleMapper.FetchForTop(Top); return Top; } } class MiddleMapper { public Middle FetchById(int id) { var middle = new Middle(DataStore.MiddleDataById(id)); middle.Parent = TopMapper.FetchForMiddle(middle); middle.Children = BottomMapper.FetchForMiddle(bottom); return middle; } } This way I can have one mapper per data store, and build the object from the mapper I want, and then save it back using the mapper I want. There is a circular reference here, but I guess that's not a problem because most languages can just store memory references to the objects, so there won't actually be infinite data. The problem with this is that every time I want to construct a new Top, Middle or Bottom, it needs to build the entire object tree within that object's Parent or Children property, with all the data store requests and memory usage that that entails. And in real life my tree is much bigger than the one represented here, so that's a problem. Requests in the object In this the objects request their Parents and Children themselves: class Middle { private List<Bottom> _children = null; // cache public List<Bottom> Children { get { _children = _children ?? BottomMapper.FetchForMiddle(this); return _children; } set { BottomMapper.UpdateForMiddle(this, value); _children = value; } } } I think this is an example of the repository pattern. Is that correct? This solution seems neat - the data only gets requested from the data store when you need it, and thereafter it's stored in the object if you want to request it again, avoiding a further request. However, I have two different data sources. There's a database, but there's also a web service, and I need to be able to create an object from the web service and save it back to the database and then request it again from the database and update the web service. This also makes me uneasy because the data objects themselves are no longer ignorant of the data source. We've introduced a new dependency, not to mention a circular dependency, making it harder to test. And the objects now mask their communication with the database. Other solutions Are there any other solutions which could take care of the multiple stores problem but also mean that I don't need to build / request all the data every time?

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• Ask the Readers: How Many Monitors Do You Use with Your Computer?

  - by Asian Angel

  Most people have a single monitor for their computers, many have two, and some individuals enjoy “3 monitor plus” goodness. This week we would like to know how many monitors you use with your computer. Photo by DamnedNice. A good majority of people have a single monitor that they use with their computers and that single monitor serves their needs very well. It could be that these individuals do not engage in a heavy amount of work or play on their computers…they just need to do the basics like checking e-mail, using I.M., working with photos, etc. Another possibility is the use of virtual desktop software such as Dexpot, Yodm 3D, or Sysinternals Desktops on Windows systems. Linux systems such as Ubuntu already have that wonderful multi-desktop functionality built in. The wonderful part about virtual desktops is that a single monitor can feel equivalent to a small army of monitors. The ability to separate your open windows into “categories” and spread them out across multiple desktops is definitely nice. With each passing year dual monitor setups are becoming more common. Having twice the screen real-estate visible at the same time can be extremely convenient when you are multi-tasking. Perhaps you like to monitor your system’s stats and an e-mail account on the second monitor while working with software on the first. It certainly beats having windows popping up and down on your screen constantly while keeping on top of everything! Next we have the people who have three or more monitors in use with their computers. This may be a result of the type of work they do, an experiment to see if multiple monitors are right for them, or the cool, geeky factor that comes with having all those monitors. Needless to say these individuals can induce a good amount of envy and/or inspiration in the rest of us when we see their awesome setups. Are you perfectly content with a single monitor? Do you have two or more monitors that you use? If you have two or more monitors are they actually that useful to you? Perhaps you are getting ready even now to add additional monitors to your system. Whatever your situation may be at the moment, let us know your thoughts (and possible multi-monitor plans) in the comments! How-To Geek Polls require Javascript. Please Click Here to View the Poll. Latest Features How-To Geek ETC How to Use the Avira Rescue CD to Clean Your Infected PC The Complete List of iPad Tips, Tricks, and Tutorials Is Your Desktop Printer More Expensive Than Printing Services? 20 OS X Keyboard Shortcuts You Might Not Know HTG Explains: Which Linux File System Should You Choose? HTG Explains: Why Does Photo Paper Improve Print Quality? Hidden Tracks Your Stolen Mac; Free Until End of January Why the Other Checkout Line Always Moves Faster World of Warcraft Theme for Windows 7 Ubuntu Font Family Now Available for Download Oh No! WikiLeaks Published Santa Claus’s Naughty List [Video] Remember the Milk Now Supports HTTPS Encryption for the Entire Session

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• PCI Encryption Key Management

  - by Unicorn Bob

  (Full disclosure: I'm already an active participant here and at StackOverflow, but for reasons that should hopefully be obvious, I'm choosing to ask this particular question anonymously). I currently work for a small software shop that produces software that's sold commercially to manage small- to mid-size business in a couple of fairly specialized industries. Because these industries are customer-facing, a large portion of the software is related to storing and managing customer information. In particular, the storage (and securing) of customer credit card information. With that, of course, comes PCI compliance. To make a long story short, I'm left with a couple of questions about why certain things were done the way they were, and I'm unfortunately without much of a resource at the moment. This is a very small shop (I report directly to the owner, as does the only other full-time employee), and the owner doesn't have an answer to these questions, and the previous developer is...err...unavailable. Issue 1: Periodic Re-encryption As of now, the software prompts the user to do a wholesale re-encryption of all of the sensitive information in the database (basically credit card numbers and user passwords) if either of these conditions is true: There are any NON-encrypted pieces of sensitive information in the database (added through a manual database statement instead of through the business object, for example). This should not happen during the ordinary use of the software. The current key has been in use for more than a particular period of time. I believe it's 12 months, but I'm not certain of that. The point here is that the key "expires". This is my first foray into commercial solution development that deals with PCI, so I am unfortunately uneducated on the practices involved. Is there some aspect of PCI compliance that mandates (or even just strongly recommends) periodic key updating? This isn't a huge issue for me other than I don't currently have a good explanation to give to end users if they ask why they are being prompted to run it. Question 1: Is the concept of key expiration standard, and, if so, is that simply industry-standard or an element of PCI? Issue 2: Key Storage Here's my real issue...the encryption key is stored in the database, just obfuscated. The key is padded on the left and right with a few garbage bytes and some bits are twiddled, but fundamentally there's nothing stopping an enterprising person from examining our (dotfuscated) code, determining the pattern used to turn the stored key into the real key, then using that key to run amok. This seems like a horrible practice to me, but I want to make sure that this isn't just one of those "grin and bear it" practices that people in this industry have taken to. I have developed an alternative approach that would prevent such an attack, but I'm just looking for a sanity check here. Question 2: Is this method of key storage--namely storing the key in the database using an obfuscation method that exists in client code--normal or crazy? Believe me, I know that free advice is worth every penny that I've paid for it, nobody here is an attorney (or at least isn't offering legal advice), caveat emptor, etc. etc., but I'm looking for any input that you all can provide. Thank you in advance!

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• Cloud – the forecast is improving

  - by Rob Farley

  There is a lot of discussion about “the cloud”, and how that affects people’s data stories. Today the discussion enters the realm of T-SQL Tuesday, hosted this month by Jorge Segarra. Over the years, companies have invested a lot in making sure that their data is good, and I mean every aspect of it – the quality of it, the security of it, the performance of it, and more. Experts such as those of us at LobsterPot Solutions have helped these companies with this, and continue to work with clients to make sure that data is a strong part of their business, not an oversight. Whether business intelligence systems are being utilised or not, every business needs to be able to rely on its data, and have the confidence in it. Data should be a foundation upon which a business is built. In the past, data had been stored in paper-based systems. Filing cabinets stored vital information. Today, people have server rooms with storage of various kinds, recognising that filing cabinets don’t necessarily scale particularly well. It’s easy to ‘lose’ data in a filing cabinet, when you have people who need to make sure that the sheets of paper are in the right spot, and that you know how things are stored. Databases help solve that problem, but still the idea of a large filing cabinet continues, it just doesn’t involve paper. If something happens to the physical ‘filing cabinet’, then the problems are larger still. Then the data itself is under threat. Many clients have generators in case the power goes out, redundant cables in case the connectivity dies, and spare servers in other buildings just in case they’re required. But still they’re maintaining filing cabinets. You see, people like filing cabinets. There’s something to be said for having your data ‘close’. Even if the data is not in readable form, living as bits on a disk somewhere, the idea that its home is ‘in the building’ is comforting to many people. They simply don’t want to move their data anywhere else. The cloud offers an alternative to this, and the human element is an obstacle. By leveraging the cloud, companies can have someone else look after their filing cabinet. A lot of people really don’t like the idea of this, partly because the administrators of the data, those people who could potentially log in with escalated rights and see more than they should be allowed to, who need to be trusted to respond if there’s a problem, are now a faceless entity in the cloud. But this doesn’t mean that the cloud is bad – this is simply a concern that some people may have. In new functionality that’s on its way, we see other hybrid mechanisms that mean that people can leverage parts of the cloud with less fear. Companies can use cloud storage to hold their backup data, for example, backups that have been encrypted and are therefore not able to be read by anyone (including administrators) who don’t have the right password. Companies can have a database instance that runs locally, but which has its data files in the cloud, complete with Transparent Data Encryption if needed. There can be a higher level of control, making the change easier to accept. Hybrid options allow people who have had fears (potentially very justifiable) to take a new look at the cloud, and to start embracing some of the benefits of the cloud (such as letting someone else take care of storage, high availability, and more) without losing the feeling of the data being close. @rob_farley

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• Squibbly: LibreOffice Integration Framework for the Java Desktop

  - by Geertjan

  Squibbly is a new framework for Java desktop applications that need to integrate with LibreOffice, or more generally, need office features as part of a Java desktop solution that could include, for example, JavaFX components. Here's what it looks like, right now, on Ubuntu 13.04: Why is the framework called Squibbly? Because I needed a unique-ish name, because "squibble" sounds a bit like "scribble" (which is what one does with text documents, etc), and because of the many absurd definitions in the Urban Dictionary for the apparently real word "squibble", e.g., "A name for someone who is squibblish in nature." And, another e.g., "A squibble is a small squabble. A squabble is a little skirmish." But the real reason is the first definition (and definitely not the fourth definition): "Taking a small portion of another persons something, such as a small hit off of a pipe, a bite of food, a sip of a drink, or drag of a cigarette." In other words, I took (or "squibbled") a small portion of LibreOffice, i.e., OfficeBean, and integrated it into a NetBeans Platform application. Now anyone can add new features to it, to do anything they need, such as create a legislative software system as Propylon has done with their own solution on the NetBeans Platform: For me, the starting point was Chuk Munn Lee's similar solution from some years ago. However, he uses reflection a lot in that solution, because he didn't want to bundle the related JARs with the application. I understand that benefit but I find it even more beneficial to not need to require the user to specify the location of the LibreOffice location, since all the necessary JARs and native libraries (currently 32-bit Linux only, by the way) are bundled with the application. Plus, hundreds of lines of reflection code, as in Chuk's solution, is not fun to work with at all. Switching between applications is done like this: It's a work in progress, a proof of concept only. Just the result of a few hours of work to get the basic integration to work. Several problems remain, some of them potentially unsolvable, starting with these, but others will be added here as I identify them: Window management problems. I'd like to let the user have multiple LibreOffice applications and documents open at the same time, each in a new TopComponent. However, I haven't figured out how to do that. Right now, each application is opened into the same TopComponent, replacing the currently open application. I don't know the OfficeBean API well enough, e.g., should a single OfficeBean be shared among multiple TopComponents or should each of them have their own instance of it? Focus problems. When putting the application behind other applications and then switching back to the application, typing text becomes impossible. When closing a TopComponent and reopening it, the content is lost completely. Somehow the loss of focus, and then the return of focus, disables something. No idea how to fix that. The project is checked into this location, which isn't public yet, so you can't access it yet. Once it's publicly available, it would be great to get some code contributions and tweaks, etc. https://java.net/projects/squibbly Here's the source structure, showing especially how the OfficeBean JARs and native libraries (currently for Linux 32-bit only) fit in: Ultimately, would be cool to integrate or share code with http://joeffice.com!

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• Auto-organized / smart inventory system?

  - by VeXe

  for the past week I've been working on an inventory system with Unity3D. At first I got help from the guys at Design3 but it wasn't too long till we split path, because I really didn't like the way they did their code, it didn't have any smell of OOP whatsoever. I took it further steps ahead - items take more than one slot, advanced placement system (items tries their best to find the best close fit), local mouse system (mouse gets trapped in active bag area), etc. Here's a demo of my work. What we would like to have in our game, is an auto-organizing feature - not auto-sort. We want this feature because our inventory's going to be in 'real-time' - not like in Resident Evil 1,2,3 etc where you would pause the game and do things in your inventory. Now imagine your self in a sticky situation surrounded by zombies, and you don't have bullets, you look around, you see that there are bullets nearby on the ground, so you go for them and try to pick them up, but they don't fit! you look at your inventory and find out that if you reorganize some of the items, it will fit! - now the player - in that situation doesn't have time to reorganize because he's surrounded with zombies and will die if he stops and organizes the inventory to make space (remember inventory in real-time, no pausing) - wouldn't it be nice for that to happen automatically? - Yes! (I believe this has been implemented in some games like Dungeon siege or something, so sure it's doable) take a look at this picture for example: Yes, so if you auto-sort the issue you will get your spaces but it's bad because: 1- Expensive: it doesn't need a whole sort operation to free those spaces, in the first picture, just slide the red item at the bottom to the very left, and you get the same spaces that you got from the auto-sort. 2- It's annoying to the player: "Who the F told you to re-order my stuff?" I'm not asking for "How to write the code" for this, I'm just asking for some guidance, where to look, what algorithms are involved? Is this something related to graphs and shortest path stuff? I hope not cuz I didn't manage to continue my college studies :/ But even if it is, just tell me and I will learn the stuff related. Notice there could be more than just one solution. So I guess the first thing I have to do is figure out if the situation is 'solvable' - if I know how to determine if a situation is solvable or not, then I can 'solve' it. I just need to know the conditions that makes it 'solvable'. And I believe there must be some algorithm/data structure for this. Here's a pic for more than one solution of trying to fit a 1x3 item: The arrows show just one of the solutions, but if you look you will find more than one. This is what I ultimately not auto-sorting but find a solution and applying it. Note that if I spend time on it I will come up with a way to solve it, but it wouldn't be the best way, it's like, holding a car wheel with your feet instead of your hands! XD Or just like trying to solve an issue that requires arrays, but you're not yet aware of their existence! So what is the right approach to this? Hope somebody helps, thanks a lot in advance :)

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• Application Logging needs work

  Application Logging Application logging is the act of logging events that occur within an application much like how a court report documents what happens in court case. Application logs can be useful for several reasons, but the most common use for logs is to recreate steps to find the root cause of applications errors. Other uses can include the detection of Fraud, verification of user activity, or provide audits on user/data interactions. “Logs can contain different kinds of data. The selection of the data used is normally affected by the motivation leading to the logging. “ (OWASP, 2009) OWASP also stats that logging include applicable debugging information like the event date time, responsible process, and a description of the event. “There are many reasons why a logging system is a necessary part of delivering a distributed application. One of the most important is the ability to track exactly how many users are using the application during different time periods.” (Hatton, 2000) Hatton also states that application logging helps system designers determine whether parts of an application aren't being used as designed. He implies that low usage can be used to identify if users like or do not like aspects of a system based on user usage of the application. This enables application designers to extract why users don't like aspects of an application so that changes can be made to increase its usefulness and effectiveness. “Logging memory usage can also assist you in tuning up the internals of your application. If you're experiencing a randomly occurring problem, being able to match activities performed with the memory status at the time may enable you to discover the cause of the problem. It also gives you a good indication of the health of the distributed server machine at the time any activity is performed. “ (Hatton, 2000) Commonly Logged Application Events (Defined by OWASP) Access of Data Creation of Data Modification of Data in any form Administrative Functions  Configuration Changes Debugging Information(Application Events)  Authorization Attempts  Data Deletion Network Communication  Authentication Events  Errors/Exceptions Application Error Logging The functionality associated with application error logging is actually the combination of proper error handling and applications logging.  If we look back at Figure 4 and Figure 5, these code examples allow developers to handle various types of errors that occur within the life cycle of an application’s execution. Application logging can be applied within the Catch section of the TryCatch statement allowing for the errors to be logged when they occur. By placing the logging within the Catch section specific error details can be accessed that help identify the source of the error, the path to the error, what caused the error and definition of the error that occurred. This can then be logged and reviewed at a later date in order recreate the error that was received based data found in the application log. By allowing applications to log errors developers IT staff can use them to recreate errors that are encountered by end-users or other dependent systems.

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• Obfuscation is not a panacea

  - by simonc

  So, you want to obfuscate your .NET application. My question to you is: Why? What are your aims when your obfuscate your application? To protect your IP & algorithms? Prevent crackers from breaking your licensing? Your boss says you need to? To give you a warm fuzzy feeling inside? Obfuscating code correctly can be tricky, it can break your app if applied incorrectly, it can cause problems down the line. Let me be clear - there are some very good reasons why you would want to obfuscate your .NET application. However, you shouldn't be obfuscating for the sake of obfuscating. Security through Obfuscation? Once your application has been installed on a user’s computer, you no longer control it. If they do not want to pay for your application, then nothing can stop them from cracking it, even if the time cost to them is much greater than the cost of actually paying for it. Some people will not pay for software, even if it takes them a month to crack a $30 app. And once it is cracked, there is nothing stopping them from putting the result up on the internet. There should be nothing suprising about this; there is no software protection available for general-purpose computers that cannot be cracked by a sufficiently determined attacker. Only by completely controlling the entire stack – software, hardware, and the internet connection, can you have even a chance to be uncrackable. And even then, someone somewhere will still have a go, and probably succeed. Even high-end cryptoprocessors have known vulnerabilities that can be exploited by someone with a scanning electron microscope and lots of free time. So, then, why use obfuscation? Well, the primary reason is to protect your IP. What obfuscation is very good at is hiding the overall structure of your program, so that it’s very hard to figure out what exactly the code is doing at any one time, what context it is running in, and how it fits in with the rest of the application; all of which you need to do to understand how the application operates. This is completely different to cracking an application, where you simply have to find a single toggle that determines whether the application is licensed or not, and flip it without the rest of the application noticing. However, again, there are limitations. An obfuscated application still has to run in the same way, and do the same thing, as the original unobfuscated application. This means that some of the protections applied to the obfuscated assembly have to be undone at runtime, else it would not run on the CLR and do the same thing. And, again, since we don’t control the environment the application is run on, there is nothing stopping a user from undoing those protections manually, and reversing some of the obfuscation. It’s a perpetual arms race, and it always will be. We have plenty of ideas lined about new protections, and the new protections added in SA 6.6 (method parent obfuscation and a new control flow obfuscation level) are specifically designed to be harder to reverse and reconstruct the original structure. So then, by all means, obfuscate your application if you want to protect the algorithms and what the application does. That’s what SmartAssembly is designed to do. But make sure you are clear what a .NET obfuscator can and cannot protect you against, and don’t expect your obfuscated application to be uncrackable. Someone, somewhere, will crack your application if they want to and they don’t have anything better to do with their time. The best we can do is dissuade the casual crackers and make it much more difficult for the serious ones. Cross posted from Simple Talk.

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• Difficulties with rotation of a sprite

  - by Andy

  I want to program a dolphin that jumps and rotates like a real dolphin. Jumping is not the problem, but I don't know how to make the rotation. My dolphin always rests in the same angle while it jumps. But I want that it changes the rotation during the jump, like a real dolphin does. How can I improve the rotation? public class Game1 : Microsoft.Xna.Framework.Game { GraphicsDeviceManager graphics; SpriteBatch spriteBatch; Texture2D image, water; float Gravity = 5.0F; float Acceleration = 20.0F; Vector2 Position = new Vector2(1200,720); Vector2 Velocity; float rotation = 0; SpriteEffects flip; Vector2 Speed = new Vector2(0, 0); public Game1() { graphics = new GraphicsDeviceManager(this); Content.RootDirectory = "Content"; graphics.PreferredBackBufferWidth = 1280; graphics.PreferredBackBufferHeight = 720; } protected override void Initialize() { base.Initialize(); } protected override void LoadContent() { spriteBatch = new SpriteBatch(GraphicsDevice); image = Content.Load<Texture2D>("cartoondolphin"); water = Content.Load<Texture2D>("background"); flip = SpriteEffects.None; } protected override void Update(GameTime gameTime) { float VelocityX = 0f; float VelocityY = 0f; float time = (float)gameTime.ElapsedGameTime.TotalSeconds; KeyboardState kbState = Keyboard.GetState(); if(kbState.IsKeyDown(Keys.Left)) { rotation = 0; flip = SpriteEffects.None; VelocityX += -5f; } if(kbState.IsKeyDown(Keys.Right)) { rotation = 0; flip = SpriteEffects.FlipHorizontally; VelocityX += 5f; } // jump if the dolphin is under water if(Position.Y >= 670) { if (kbState.IsKeyDown(Keys.A)) { if (flip == SpriteEffects.None) { rotation = 45; VelocityY += 40f; } else { rotation = -45; VelocityY += 40f; } } } else { VelocityY += -10f; } float deltaY = 0; float deltaX = 0; deltaY = Gravity * (float)gameTime.ElapsedGameTime.TotalSeconds; deltaX += VelocityX * (float)gameTime.ElapsedGameTime.TotalSeconds * Acceleration; deltaY += -VelocityY * (float)gameTime.ElapsedGameTime.TotalSeconds * Acceleration; Speed = new Vector2(Speed.X + deltaX, Speed.Y + deltaY); Position += Speed * (float)gameTime.ElapsedGameTime.TotalSeconds; Velocity.X = 0; if (Position.Y + image.Height/2 > graphics.PreferredBackBufferHeight) Position.Y = graphics.PreferredBackBufferHeight - image.Height/2; base.Update(gameTime); } protected override void Draw(GameTime gameTime) { GraphicsDevice.Clear(Color.CornflowerBlue); spriteBatch.Begin(); spriteBatch.Draw(water, new Rectangle(0, graphics.PreferredBackBufferHeight -100, graphics.PreferredBackBufferWidth, 100), Color.White); spriteBatch.Draw(image, Position, null, Color.White, MathHelper.ToRadians(rotation), new Vector2(image.Width / 2, image.Height / 2), 1, flip, 1); spriteBatch.End(); base.Draw(gameTime); } }

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• Optimal Data Structure for our own API

  - by vermiculus

  I'm in the early stages of writing an Emacs major mode for the Stack Exchange network; if you use Emacs regularly, this will benefit you in the end. In order to minimize the number of calls made to Stack Exchange's API (capped at 10000 per IP per day) and to just be a generally responsible citizen, I want to cache the information I receive from the network and store it in memory, waiting to be accessed again. I'm really stuck as to what data structure to store this information in. Obviously, it is going to be a list. However, as with any data structure, the choice must be determined by what data is being stored and what how it will be accessed. What, I would like to be able to store all of this information in a single symbol such as stack-api/cache. So, without further ado, stack-api/cache is a list of conses keyed by last update: `(<csite> <csite> <csite>) where <csite> would be (1362501715 . <site>) At this point, all we've done is define a simple association list. Of course, we must go deeper. Each <site> is a list of the API parameter (unique) followed by a list questions: `("codereview" <cquestion> <cquestion> <cquestion>) Each <cquestion> is, you guessed it, a cons of questions with their last update time: `(1362501715 <question>) (1362501720 . <question>) <question> is a cons of a question structure and a list of answers (again, consed with their last update time): `(<question-structure> <canswer> <canswer> <canswer> and ` `(1362501715 . <answer-structure>) This data structure is likely most accurately described as a tree, but I don't know if there's a better way to do this considering the language, Emacs Lisp (which isn't all that different from the Lisp you know and love at all). The explicit conses are likely unnecessary, but it helps my brain wrap around it better. I'm pretty sure a <csite>, for example, would just turn into (<epoch-time> <api-param> <cquestion> <cquestion> ...) Concerns: Does storing data in a potentially huge structure like this have any performance trade-offs for the system? I would like to avoid storing extraneous data, but I've done what I could and I don't think the dataset is that large in the first place (for normal use) since it's all just human-readable text in reasonable proportion. (I'm planning on culling old data using the times at the head of the list; each inherits its last-update time from its children and so-on down the tree. To what extent this cull should take place: I'm not sure.) Does storing data like this have any performance trade-offs for that which must use it? That is, will set and retrieve operations suffer from the size of the list? Do you have any other suggestions as to what a better structure might look like?

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• Cloud Adoption Challenges

  - by Herve Roggero

  Originally posted on: http://geekswithblogs.net/hroggero/archive/2013/11/07/cloud-adoption-challenges.aspxWhile cloud computing makes sense for most organizations and countless projects, I have seen customers significantly struggle with cloud adoption challenges. This blog post is not an attempt to provide a generic assessment of cloud adoption; rather it is an account of personal experiences in the field, some of which may or may not apply to your organization. Cloud First, Burst? In the rush to cloud adoption some companies have made the decision to redesign their core system with a cloud first approach. However a cloud first approach means that the system may not work anymore on-premises after it has been redesigned, specifically if the system depends on Platform as a Service (PaaS) components (such as Azure Tables). While PaaS makes sense when your company is in a position to adopt the cloud exclusively, it can be difficult to leverage with systems that need to work in different clouds or on-premises. As a result, some companies are starting to rethink their cloud strategy by designing for on-premises first, and modify only the necessary components to burst when needed in the cloud. This generally means that the components need to work equally well in any environment, which requires leveraging Infrastructure as a Service (IaaS) or additional investments for PaaS applications, or both.  What’s the Problem? Although most companies can benefit from cloud computing, not all of them can clearly identify a business reason for doing so other than in very generic terms. I heard many companies claim “it’s cheaper”, or “it allows us to scale”, without any specific metric or clear strategy behind the adoption decision. Other companies have a very clear strategy behind cloud adoption and can precisely articulate business benefits, such as “we have a 500% increase in traffic twice a year, so we need to burst in the cloud to avoid doubling our network and server capacity”. Understanding the problem being solved through by adopting cloud computing can significantly help organizations determine the optimum path and timeline to adoption. Performance or Scalability? I stopped counting the number of times I heard “the cloud doesn’t scale; our database runs faster on a laptop”.  While performance and scalability are related concepts, they are nonetheless different in nature. Performance is a measure of response time under a given load (meaning with a specific number of users), while scalability is the performance curve over various loads. For example one system could see great performance with 100 users, but timeout with 1,000 users, in which case the system wouldn’t scale. However another system could have average performance with 100 users, but display the exact same performance with 1,000,000 users, in which case the system would scale. Understanding that cloud computing does not usually provide high performance, but instead provides the tools necessary to build a scalable system (usually using PaaS services such as queuing and data federation), is fundamental to proper cloud adoption. Uptime? Last but not least, you may want to read the Service Level Agreement of your cloud provider in detail if you haven’t done so. If you are expecting 99.99% uptime annually you may be in for a surprise. Depending on the component being used, there may be no associated SLA at all! Other components may be restarted at any time, or services may experience failover conditions weekly ( or more) based on current overall conditions of the cloud service provider, most of which are outside of your control. As a result, for PaaS cloud environments (and to a certain extent some IaaS systems), applications need to assume failure and gracefully retry to be successful in the cloud in order to provide service continuity to end users. About Herve Roggero Herve Roggero, Windows Azure MVP, is the founder of Blue Syntax Consulting (http://www.bluesyntax.net). Herve's experience includes software development, architecture, database administration and senior management with both global corporations and startup companies. Herve holds multiple certifications, including an MCDBA, MCSE, MCSD. He also holds a Master's degree in Business Administration from Indiana University. Herve is the co-author of "PRO SQL Azure" and “PRO SQL Server 2012 Practices” from Apress, a PluralSight author, and runs the Azure Florida Association.

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• How to make a stack stable? Need help for an explicit resting contact scheme (2-dimensional)

  - by Register Sole

  Previously, I struggle with the sequential impulse-based method I developed. Thanks to jedediah referring me to this paper, I managed to rebuild the codes and implement the simultaneous impulse based method with Projected-Gauss-Seidel (PGS) iterative solver as described by Erin Catto (mentioned in the reference of the paper as [Catt05]). So here's how it currently is: The simulation handles 2-dimensional rotating convex polygons. Detection is using separating-axis test, with a SKIN, meaning closest points between two polygons is detected and determined if their distance is less than SKIN. To resolve collision, simultaneous impulse-based method is used. It is solved using iterative solver (PGS-solver) as in Erin Catto's paper. Error-correction is implemented using Baumgarte's stabilization (you can refer to either paper for this) using J V = beta/dt*overlap, J is the Jacobian for the constraints, V the matrix containing the velocities of the bodies, beta an error-correction parameter that is better be < 1, dt the time-step taken by the engine, and overlap, the overlap between the bodies (true overlap, so SKIN is ignored). However, it is still less stable than I expected :s I tried to stack hexagons (or squares, doesn't really matter), and even with only 4 to 5 of them, they would swing! Also note that I am not looking for a sleeping scheme. But I would settle if you have any explicit scheme to handle resting contacts. That said, I would be more than happy if you have a way of treating it generally (as continuous collision, instead of explicitly as a special state). Ideas I have tried: Using simultaneous position based error correction as described in the paper in section 5.3.2, turned out to be worse than the current scheme. If you want to know the parameters I used: Hexagons, side 50 (pixels) gravity 2400 (pixels/sec^2) time-step 1/60 (sec) beta 0.1 restitution 0 to 0.2 coeff. of friction 0.2 PGS iteration 10 initial separation 10 (pixels) mass 1 (unit is irrelevant for now, i modified velocity directly<-impulse method) inertia 1/1000 Thanks in advance! I really appreciate any help from you guys!! :) EDIT In response to Cholesky's comment about warm starting the solver and Baumgarte: Oh right, I forgot to mention! I do save the contact history and the impulse determined in this time step to be used as initial guess in the next time step. As for the Baumgarte, here's what actually happens in the code. Collision is detected when the bodies' closest distance is less than SKIN, meaning they are actually still separated. If at this moment, I used the PGS solver without Baumgarte, restitution of 0 alone would be able to stop the bodies, separated by a distance of ~SKIN, in mid-air! So this isn't right, I want to have the bodies touching each other. So I turn on the Baumgarte, where its role is actually to pull the bodies together! Weird I know, a scheme intended to push the body apart becomes useful for the reverse. Also, I found that if I increase the number of iteration to 100, stacks become much more stable, though the program becomes so slow. UPDATE Since the stack swings left and right, could it be something is wrong with my friction model? Current friction constraint: relative_tangential_velocity = 0

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• What do you need to know to be a world-class master software developer? [closed]

  - by glitch

  I wanted to bring up this question to you folks and see what you think, hopefully advise me on the matter: let's say you had 30 years of learning and practicing software development in front of you, how would you dedicate your time so that you'd get the biggest bang for your buck. What would you both learn and work on to be a world-class software developer that would make a large impact on the industry and leave behind a legacy? I think that most great developers end up being both broad generalists and specialists in one-two areas of interest. I'm thinking Bill Joy, John Carmack, Linus Torvalds, K&R and so on. I'm thinking that perhaps one approach would be to break things down by categories and establish a base minimum of "software development" greatness. I'm thinking: Operating Systems: completely internalize the core concepts of OS, perhaps gain a lot of familiarity with an OSS one such as Linux. Anything from memory management to device drivers has to be complete second nature. Programming Languages: this is one of those topics that imho has to be fully grokked even if it might take many years. I don't think there's quite anything like going through the process of developing your own compiler, understanding language design trade-offs and so on. Programming Language Pragmatics is one of my favorite books actually, I think you want to have that internalized back to back, and that's just the start. You could go significantly deeper, but I think it's time well spent, because it's such a crucial building block. As a subset of that, you want to really understand the different programming paradigms out there. Imperative, declarative, logic, functional and so on. Anything from assembly to LISP should be at the very least comfortable to write in. Contexts: I believe one should have experience working in different contexts to truly be able to appreciate the trade-offs that are being made every day. Embedded, web development, mobile development, UX development, distributed, cloud computing and so on. Hardware: I'm somewhat conflicted about this one. I think you want some understanding of computer architecture at a low level, but I feel like the concepts that will truly matter will be slightly higher level, such as CPU caching / memory hierarchy, ILP, and so on. Networking: we live in a completely network-dependent era. Having a good understanding of the OSI model, knowing how the Web works, how HTTP works and so on is pretty much a pre-requisite these days. Distributed systems: once again, everything's distributed these days, it's getting progressively harder to ignore this reality. Slightly related, perhaps add solid understanding of how browsers work to that, since the world seems to be moving so much to interfacing with everything through a browser. Tools: Have a really broad toolset that you're familiar with, one that continuously expands throughout the years. Communication: I think being a great writer, effective communicator and a phenomenal team player is pretty much a prerequisite for a lot of a software developer's greatness. It can't be overstated. Software engineering: understanding the process of building software, team dynamics, the requirements of the business-side, all the pitfalls. You want to deeply understand where what you're writing fits from the market perspective. The better you understand all of this, the more of your work will actually see the daylight. This is really just a starting list, I'm confident that there's a ton of other material that you need to master. As I mentioned, you most likely end up specializing in a bunch of these areas as you go along, but I was trying to come up with a baseline. Any thoughts, suggestions and words of wisdom from the grizzled veterans out there who would like to share their thoughts and experiences with this? I'd really love to know what you think!

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• Hosted Monitoring

  - by Grant Fritchey

  The concept of using services to take the place of writing a lot of your own code goes way, way back in computing history. The fundamentals of the concept go back to the dawn of computing with places like IBM hosting time-shares for computing power that you could rent for short periods of time. But things really took off with the building of the Web. Now, all the growth with virtual machines, hosted machines, hosted services from vendors like Amazon and Microsoft, the need to keep all of your software locally on physical boxes is just going the way of the dodo. There will likely always be some pieces of software that you keep on machines on your property or on your person, but the concept of keeping fundamental services locally is going away. As someone put it to me once, if you were starting a business right now, would you bother setting up an Exchange server to manage your email or would you just go to one of the external mail services for everything? For most of us (who are not Exchange admins) the answer is pretty easy. With all this momentum to having external services manage more and more of the infrastructure that’s not business unique, why would you burn up a server and license instance setting up monitoring for your SQL Servers? Of course, some of you are dealing with hyper-sensitive data that might require, through law or treaty, that you lock it down and never expose it to the intertubes, but most of us are not. So, what if someone else took on the basic hassle of setting up monitoring on your systems? That’s what we’re working on here at Red Gate. Right now it’s a private test, but we’re growing it and developing it and it’ll be going to a public beta, probably (hopefully) this year. I’m running it on my machines right now. The concept is pretty simple. You put a relay on your server, poke a hole in your firewall for it, and we start monitoring your server using SQL Monitor. It’s actually shocking how easy it is to get going. You still have to adjust your alerting thresholds, but that’s a standard part of alerting. Your pain threshold and my pain threshold for any given alert may be different. But from there, we do all the heavy lifting, keeping your data online and available, providing you with access to the information about how your servers are behaving, everything. Maybe it’s just me, but I’m really excited by this. I think we’re getting to a place where we can really help the small and medium sized businesses get a monitoring solution in place, quickly and easily. All you crazy busy, and possibly accidental, DBAs and system admins finally can set up monitoring without taking all the time to configure systems, run installs, and all the rest. You just have to tweak your alerts and you’re ready to run. If you are interested in checking it out, you can apply for the closed beta through the Monitor web page.

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• Is there any kind of established architecture for browser based games?

  - by black_puppydog

  I am beginning the development of a broser based game in which players take certain actions at any point in time. Big parts of gameplay will be happening in real life and just have to be entered into the system. I believe a good kind of comparison might be a platform for managing fantasy football, although I have virtually no experience playing that, so please correct me if I am mistaken here. The point is that some events happen in the program (i.e. on the server, out of reach for the players) like pulling new results from some datasource, starting of a new round by a game master and such. Other events happen in real life (two players closing a deal on the transfer of some team member or whatnot - again: have never played fantasy football) and have to be entered into the system. The first part is pretty easy since the game masters will be "staff" and thus can be trusted to a certain degree to not mess with the system. But the second part bothers me quite a lot, especially since the actions may involve multiple steps and interactions with different players, like registering a deal with the system that then has to be approved by the other party or denied and passed on to a game master to decide. I would of course like to separate the game logic as far as possible from the presentation and basic form validation but am unsure how to do this in a clean fashion. Of course I could (and will) put some effort into making my own architectural decisions and prototype different ideas. But I am bound to make some stupid mistakes at some point, so I would like to avoid some of that by getting a little "book smart" beforehand. So the question is: Is there any kind of architectural works that I can read up on? Papers, blogs, maybe design documents or even source code? Writing this down this seems more like a business application with business rules, workflows and such... Any good entry points for that? EDIT: After reading the first answers I am under the impression of having made a mistake when including the "MMO" part into the title. The game will not be all fancy (i.e. 3D or such) on the client side and the logic will completely exist on the server. That is, apart from basic form validation for the user which will also be mirrored on the server side. So the target toolset will be HTML5, JavaScript, probably JQuery(UI). My question is more related to the software architecture/design of a system that enforces certain rules. Separation of ruleset and presentation One problem I am having is that I want to separate the game rules from the presentation. The first step would be to make an own module for the game "engine" that only exposes an interface that allows all actions to be taken in a clean way. If an action fails with regard to some pre/post condition, the engine throws an exception which is then presented to the user like "you cannot sell something you do not own" or "after that you would end up in a situation which is not a valid game state." The problem here is that I would like to be able to not even present invalid action in the first place or grey out the corresponding UI elements. Changing and tweaking the ruleset Another big thing is the ruleset. It will probably evolve over time and most definitely must be tweaked. What's more, it should be possible (to a certain extent) to build a ruleset that fits a specific game round, i.e. choosing different kinds of behaviours in different aspects of the game. This would do something like "we play it with extension A today but we throw out extension B." For me, this screams "Architectural/Design pattern" but I have no idea on who might have published on something like this, not even what to google for.

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• Multitenancy in SQL Azure

  - by cibrax

  If you are building a SaaS application in Windows Azure that relies on SQL Azure, it’s probably that you will need to support multiple tenants at database level. This is short overview of the different approaches you can use for support that scenario, A different database per tenant A new database is created and assigned when a tenant is provisioned. Pros Complete isolation between tenants. All the data for a tenant lives in a database only he can access. Cons It’s not cost effective. SQL Azure databases are not cheap, and the minimum size for a database is 1GB.  You might be paying for storage that you don’t really use. A different connection pool is required per database. Updates must be replicated across all the databases You need multiple backup strategies across all the databases Multiple schemas in a database shared by all the tenants A single database is shared among all the tenants, but every tenant is assigned to a different schema and database user. Pros You only pay for a single database. Data is isolated at database level. If the credentials for one tenant is compromised, the rest of the data for the other tenants is not. Cons You need to replicate all the database objects in every schema, so the number of objects can increase indefinitely. Updates must be replicated across all the schemas. The connection pool for the database must maintain a different connection per tenant (or set of credentials) A different user is required per tenant, which is stored at server level. You have to backup that user independently. Centralizing the database access with store procedures in a database shared by all the tenants A single database is shared among all the tenants, but nobody can read the data directly from the tables. All the data operations are performed through store procedures that centralize the access to the tenant data. The store procedures contain some logic to map the database user to an specific tenant. Pros You only pay for a single database. You only have a set of objects to maintain and backup. Cons There is no real isolation. All the data for the different tenants is shared in the same tables. You can not use traditional ORM like EF code first for consuming the data. A different user is required per tenant, which is stored at server level. You have to backup that user independently. SQL Federations A single database is shared among all the tenants, but a different federation is used per tenant. A federation in few words, it’s a mechanism for horizontal scaling in SQL Azure, which basically uses the idea of logical partitions to distribute data based on certain criteria. Pros You only have a single database with multiple federations. You can use filtering in the connections to pick the right federation, so any ORM could be used to consume the data. Cons There is no real isolation at that database level. The isolation is enforced programmatically with federations.

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• Making user input/math on data fast, unlike excel type programs

  - by proGrammar

  I'm creating a research platform solely for myself to do some research on data. Programs like excel are terribly slow for me so I'm trying to come up with another solution. Originally I used excel. A1 was the cell that contained the data and all other cells in use calculated something on A1, or on other cells, that all could be in the end traced to A1. A1 was like an element of an array, I then I incremented it to go through all my data. This was way too slow. So the only other option I found originally was to hand code in c# the calculations inside a loop. Then I simply recompiled each time I changed my math. This was terribly slow to do and I had to order everything correctly so things would update correctly (dependencies). I could have also used events, but hand coding events for each cell like calculation would also be very slow. Next I created an application to read Excel and to perfectly imitate it. Which is what I now use. Basically I write formulas onto a fraction of my data to get live results inside excel. Then my program reads excel, writes another c# program, compiles it, and runs that program which runs my excel created formulas through a lot more data a whole lot faster. The advantage being my application dependency sorts everything (or I could use events) so I don't have to (like excel does) And of course the speed. But now its not a single application anymore. Instead its 2 applications, one which only reads my formulas and writes another program. The other one being the result which only lives for a short while before I do other runs through my data with different formulas / settings. So I can't see multiple results at one time without introducing even more programs like a database or at least having the 2 applications talking to each other. My idea was to have a dll that would be written, compiled, loaded, and unloaded again and again. So a self-updating program, sort of. But apparently that's not possible without another appdomain which means data has to be marshaled to be moved between the appdomains. Which would slow things down, not for summaries, but for other stuff I need to do with all my data. I'm also forgetting to mention a huge problem with restarting an application again and again which is having to reload ALL my data into memory again and again. But its still a whole lot faster than excel. I'm really super puzzled as to what people do when they want to research data fast. I'm completely unable to have a program accept user input and having it fast. My understanding is that it would have to do things like excel which is to evaluate strings again and again. So my only option is to repeatedly compile applications. Do I have a correct understanding on computer science? I've only just began programming, and didn't think I would have to learn much to do some simple math on data. My understanding is its either compiling my user defined stuff to a program or evaluating them from a string or something stupid again and again. And my only option is to probably switch operating systems or something to be able to have a program compile and run itself without stopping (writing/compiling dll, loading dll to program, unloading, and repeating). Can someone give me some idea on how computers work? Is anything better possible? Like a running program, that can accept user input and compile it and then unload it later? I mean heck operating systems dont need to be RESTARTED with every change to user input. What is this the cave man days? Sorry, it's just so super frustrating not knowing what one can do, and can't do. If only I could understand and learn this stuff fast enough.

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• Web Service Exception Handling

  - by SchlaWiener

  I have a Winforms app that consumes a C# Webservice. If the WebService throws an Exception my Client app always get's a SoapException instead of the "real" Exception. Here's a demo: [WebService(Namespace = "http://tempuri.org/")] [WebServiceBinding(ConformsTo = WsiProfiles.BasicProfile1_1)] [System.ComponentModel.ToolboxItem(false)] public class Service1 : System.Web.Services.WebService { [WebMethod] public string HelloWorld() { throw new IndexOutOfRangeException("just a demo exception"); } } Now, on the client side, I want to be able to handle different exceptions in a different way. try { ServiceReference1.Service1SoapClient client = new ServiceReference1.Service1SoapClient(); Button1.Text = client.HelloWorld(); } catch (IndexOutOfRangeException ex) { // I know how to handle IndexOutOfRangeException // but this block is never reached } catch (MyOwnException ex) { // I know how to handle MyOwnException // but this block is never reached } catch (System.ServiceModel.FaultException ex) { // I always end in this block } But that does not work because I always get a "System.ServiceModel.FaultException" and I can only figure out the "real" exception by parsing the Exception's message property: System.Web.Services.Protocols.SoapException: Server was unable to process request. ---> System.IndexOutOfRangeException: just a demo\n at SoapExceptionTest.Service1.Service1.HelloWorld() in ... --- End of inner exception stack trace --- Is there a way to make this work somehow?

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