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  • Database Rebuild

    - by Robert May
    I promised I’d have a simpler mechanism for rebuilding the database.  Below is a complete MSBuild targets file for rebuilding the database from scratch.  I don’t know if I’ve explained the rational for this.  The reason why you’d WANT to do this is so that each developer has a clean version of the database on their local machine.  This also includes the continuous integration environment.  Basically, you can do whatever you want to the database without fear, and in a minute or two, have a completely rebuilt database structure. DBDeploy (including the KTSC build task for dbdeploy) is used in this script to do change tracking on the database itself.  The MSBuild ExtensionPack is used in this target file.  You can get an MSBuild DBDeploy task here. There are two database scripts that you’ll see below.  First is the task for creating an admin (dbo) user in the system.  This script looks like the following: USE [master] GO If not Exists (select Name from sys.sql_logins where name = '$(User)') BEGIN CREATE LOGIN [$(User)] WITH PASSWORD=N'$(Password)', DEFAULT_DATABASE=[$(DatabaseName)], CHECK_EXPIRATION=OFF, CHECK_POLICY=OFF END GO EXEC master..sp_addsrvrolemember @loginame = N'$(User)', @rolename = N'sysadmin' GO USE [$(DatabaseName)] GO CREATE USER [$(User)] FOR LOGIN [$(User)] GO ALTER USER [$(User)] WITH DEFAULT_SCHEMA=[dbo] GO EXEC sp_addrolemember N'db_owner', N'$(User)' GO The second creates the changelog table.  This script can also be found in the dbdeploy.net install\scripts directory. CREATE TABLE changelog ( change_number INTEGER NOT NULL, delta_set VARCHAR(10) NOT NULL, start_dt DATETIME NOT NULL, complete_dt DATETIME NULL, applied_by VARCHAR(100) NOT NULL, description VARCHAR(500) NOT NULL ) GO ALTER TABLE changelog ADD CONSTRAINT Pkchangelog PRIMARY KEY (change_number, delta_set) GO Finally, Here’s the targets file. <Projectxmlns="http://schemas.microsoft.com/developer/msbuild/2003" ToolsVersion="4.0" DefaultTargets="Update">   <PropertyGroup>     <DatabaseName>TestDatabase</DatabaseName>     <Server>localhost</Server>     <ScriptDirectory>.\Scripts</ScriptDirectory>     <RebuildDirectory>.\Rebuild</RebuildDirectory>     <TestDataDirectory>.\TestData</TestDataDirectory>     <DbDeploy>.\DBDeploy</DbDeploy>     <User>TestUser</User>     <Password>TestPassword</Password>     <BCP>bcp</BCP>     <BCPOptions>-S$(Server) -U$(User) -P$(Password) -N -E -k</BCPOptions>     <OutputFileName>dbDeploy-output.sql</OutputFileName>     <UndoFileName>dbDeploy-output-undo.sql</UndoFileName>     <LastChangeToApply>99999</LastChangeToApply>   </PropertyGroup>     <ImportProject="$(MSBuildExtensionsPath)\ExtensionPack\4.0\MSBuild.ExtensionPack.tasks"/>   <UsingTask TaskName="Ktsc.Build.DBDeploy" AssemblyFile="$(DbDeploy)\Ktsc.Build.dll"/>   <ItemGroup>     <VariableInclude="DatabaseName">       <Value>$(DatabaseName)</Value>     </Variable>     <VariableInclude="Server">       <Value>$(Server)</Value>     </Variable>     <VariableInclude="User">       <Value>$(User)</Value>     </Variable>     <VariableInclude="Password">       <Value>$(Password)</Value>     </Variable>   </ItemGroup>     <TargetName="Rebuild">     <!--Take the database offline to disconnect any users. Requires that the current user is an admin of the sql server machine.-->     <MSBuild.ExtensionPack.SqlServer.SqlCmd Variables="@(Variable)" Database="$(DatabaseName)" TaskAction="Execute" CommandLineQuery ="ALTER DATABASE $(DatabaseName) SET OFFLINE WITH ROLLBACK IMMEDIATE"/>         <!--Bring it back online.  If you don't, the database files won't be deleted.-->     <MSBuild.ExtensionPack.Sql2008.DatabaseTaskAction="SetOnline" DatabaseItem="$(DatabaseName)"/>     <!--Delete the database, removing the existing files.-->     <MSBuild.ExtensionPack.Sql2008.DatabaseTaskAction="Delete" DatabaseItem="$(DatabaseName)"/>     <!--Create the new database in the default database path location.-->     <MSBuild.ExtensionPack.Sql2008.DatabaseTaskAction="Create" DatabaseItem="$(DatabaseName)" Force="True"/>         <!--Create admin user-->     <MSBuild.ExtensionPack.SqlServer.SqlCmd TaskAction="Execute" Server="(local)" Database="$(DatabaseName)" InputFiles="$(RebuildDirectory)\0002 Create Admin User.sql" Variables="@(Variable)" />     <!--Create the dbdeploy changelog.-->     <MSBuild.ExtensionPack.SqlServer.SqlCmd TaskAction="Execute" Server="(local)" Database="$(DatabaseName)" LogOn="$(User)" Password="$(Password)" InputFiles="$(RebuildDirectory)\0003 Create Changelog.sql" Variables="@(Variable)" />     <CallTarget Targets="Update;ImportData"/>     </Target>    <TargetName="Update" DependsOnTargets="CreateUpdateScript">     <MSBuild.ExtensionPack.SqlServer.SqlCmd TaskAction="Execute" Server="(local)" Database="$(DatabaseName)" LogOn="$(User)" Password="$(Password)" InputFiles="$(OutputFileName)" Variables="@(Variable)" />   </Target>   <TargetName="CreateUpdateScript">     <ktsc.Build.DBDeploy DbType="mssql"                                        DbConnection="User=$(User);Password=$(Password);Data Source=$(Server);Initial Catalog=$(DatabaseName);"                                        Dir="$(ScriptDirectory)"                                        OutputFile="..\$(OutputFileName)"                                        UndoOutputFile="..\$(UndoFileName)"                                        LastChangeToApply="$(LastChangeToApply)"/>   </Target>     <TargetName="ImportData">     <ItemGroup>       <TestData Include="$(TestDataDirectory)\*.dat"/>     </ItemGroup>     <ExecCommand="$(BCP) $(DatabaseName).dbo.%(TestData.Filename) in&quot;%(TestData.Identity)&quot;$(BCPOptions)"/>   </Target> </Project> Technorati Tags: MSBuild

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  • Rocky Mountain Tech Trifecta v3.0

    - by Jeff Certain
    The Rocky Mountain Tech Trifecta is an annual event held in Denver in late February or early March. The last couple of these have been amazing events, with great speakers like Beth Massi, Scott Hanselman, David Yack, Kathleen Dollard, Ben Hoelting, Paul Nielsen… need I go on? Registration is open at http://www.rmtechtrifecta.com. The speaker list hasn’t been finalized, but it’s sure to be another great event. Don’t miss it!

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  • 2011 - ALMs for your development team and the people they work with.

    - by David V. Corbin
    Welcome to 2011, it is already shaping up to be a very exciting year. The title of the post is not about charitable giving, although that is also a great topic. Application Lifecycle Management and the Systems that support the environment is, and 2011 will be a year where I expect many teams to invest heavily in this area. For those not familiar with ALM, it can be simplified down to "A comprehensive view of all of the iteas, requirements, activities and artifacts that impact an application over the course of its lifecycle, from concept until decommissioning". Obviously, this encompases a large number of different areas even for relatively small and medium sized projects. In recent years, many teams have adapted methodoligies which address individual aspects of this; but the majority of this adoption has resulted in "islands of improvement" rather than the desired comprehensive outcome...Until now! Last year Microsoft released Team Foundation Server 2010 along with Visual Studio 2010 Ultimate Edition, and with these two in combination the situation has drastically changed. At last there is a single environment that is capable of handling all aspects of ALM, and is also capable of dealing with migration and integration with existing systems to make the transition to a single solution much easier. Thse possibilities (and practicalities) are nothing short of amazing, Architecture thru Testing integration? YES. Being able to correlate specific requirement items (and their history) to actual code (and code history)? YES. Identification of which tests will be potentially impacted by a given code change? YES. Resiliant Automated Testing of User Interfaces? YES. Automatic Deployment Management? YES. Integraton Level testing as part of (designated) Builds? YES. I could easily double or triple the above list, but these items should be enough to get you thinking about the "pain points" your team and organization currently face and the fact that there IS a way to relieve the pain. Over the course of the year, I am hoping to bring together some of the "best of breed" information, along with hosting (and participating in) discussions with various experts in the field. There are already a number of groups (including many on LinkedIn) that have an ALM focus, and I encourage everyone out to check them out. I will be posting a list of the ones I find most helpful in the not too distant future. As I said at the beginning, 2011 is shaping up to be a very interesting (and productive) year. Why wait to start investigating and adopting ALM? ps: For those interested in becoming an "Alms Giver" in the charitable sense, I highly recommend checking out GiveCamp. A group of developers, designers and others get together to create a solution for a charity in just under 48 hours. I will be attending the GiveCamp in New York City on Jan 14-16, more information is available at nycgivecamp.org/

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  • Gotcha | Installing .net 4.0 and IIS 6

    - by Steve Clements
    Just a quick one, seems pretty weird to me. I installed .net 4.0 on an old IIS6 box, ready to deploy a asp.net mvc app targeting .net 4.0.  I thought, which to me seems logical, that I install .net 4.0, setup a new web site, new app pool, set the web site to asp.net 4.0 (other configuration also needed to run MVC on IIS6 here and here) and it would just work. Errr… No.  The page cannot be displayed!  Nothing to do with MVC. Apparently just because you have installed .net 4 and the option is available in IIS, it’s not enabled.  I’m not going to repeat anything here…take a look at this post – clear, easy steps on exactly what you need to do and how to check if this is the problem. http://johan.driessen.se/archive/2010/04/13/getting-an-asp.net-4-application-to-work-on-iis6.aspx

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  • Hell and Diplomacy: Notes on Software Integration

    - by ericajanine
    Well, I'm getting cabin fever and short-timer's ADD all at the same time. I haven't been anywhere outside of my greater city area in FOREVER and I'm only days away from my vacation. I have brainlock because the last few days have been non-stop diffusing amazingly hostile conversations. I think I'll write about that. So then, I "do" software. At the end of the day, software is pretty straightforward. Software is that thing we love and try to make do things not currently in play, in existence. If a process around getting software to do something is broken (like most actually are), then we should acknowledge it and move on. We are professional. We are helpful beyond the normal call of duty. We live and breathe making the lives better for those apps being active in the world. But above all--the shocker: We are SERVICE. In a service frame of mind, all perspectives shift to what is best overall for system stabilization vs. what must be in production to meet business objectives. It doesn't matter how much you like or dislike the creator of said software. It doesn't matter what time you went to bed last night or if your mate appreciates your Death March attitude. Getting a product in and when is an age-old dilemma in a software environment where more than, say, 3 people are involved. We know this. Taking a servant's perspective eliminates the drama surrounding what a group of half-baked developers forgot to tell each other in the 11th hour about their trampling changes before check-in. We, my counterparts in society, get paid to deal with that drama. I get paid to diffuse that drama and make everything integrate as smoothly as possible. At the end of the day, attacking someone over a minor detail not only makes things worse, it's against the whole point of our real existence. Being in support or software integration means you are to keep your eyes on the end game. That end game? It's making a solution work for all stakeholders, not just you or your immediate superior. Development and technology groups exist because business groups need them to exist and solve their issues. The end game? Doing what is best for those business groups ultimately. Period. Note: That does not mean you let your business users solely dictate when and if something gets changed in an environment you ultimately own. That's just crazy. Software and its environments are legitimately owned by those who manage it directly, no matter how important a business group believes it is to the existence of mankind. So, you both negotiate the terms of changing that environment and only do so upon that negotiation. Diplomacy is in order. So, to finish my thoughts: If you have no ability to keep your mouth shut in a situation where a business or development group truly need your help to make something work even beyond a deadline, find another profession. Beating up someone verbally because they screw up means a service attitude is not at the forefront of your motivation for doing what is ultimately their work and their product. Software, especially integration, requires a strong will and a soft touch to keep it on track. Not a hammer covered in broken glass.

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  • Clickworthy tweets, the sequel&hellip;

    - by Chris Williams
    Twitter moves fast, and if you don’t stay on top of it, you can miss a lot. I don’t follow a ton of people, but I combine it with topic searches. Here are a few things I’ve found that are worth your time and attention, especially if you’re into video games… development or playing: The 15 Greatest Sci-Fi/Horror Games for the Commodore 64 - http://moe.vg/bovATG  (via @jlist)  Practical Tactics for Dealing with Haters! - http://www.fourhourworkweek.com/blog/2010/05/18/tim-ferriss-scam-practical-tactics-for-dealing-with-haters/ (via @The_Zman) Assassin’s Creed 2 + $10 Video Game Credit + $5 MP3 Credit - $24.99 on Amazon.com – http://amzn.to/bvRI9h (via @Assassin10k) Make Small Good – A design article about not trying to compete with ginormous AAA multimillion dollar titles. - http://www.gamasutra.com/blogs/AlexanderBrandon/20100518/5067/Make_Small_Good.php (via @Kei_tchan) (CW: Excellent article, I do this a lot in my roguelike games!) Purposes for Randomization in Game Design – http://bit.ly/cAH7PG  (via @gamasutra)

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  • BizTalk 2009 - Project Creation Failed

    - by StuartBrierley
    A couple of weeks ago I had some issue with my BizTalk Server 2009 development environment  which resulted in a reinstall of Visual Studio 2008 and the Visual Studio 2008 Service Pack 1. Following this reinstall I began to have problems when trying to create  BizTalk 2009 projects: Error Details: “Create BizTalk Project …. Project Creation Failed” It turns out that this is a known issue with BizTalk Server 2009 and Visual Studio 2008, whereby the installation of the Visual Studio Service Pack 1 can cause corruption to the BizTalk installation preventing the creation of any new projects. To resolve this issue go to control panel > add or remove programs > Microsoft BizTalk Server 2009 and select Change or Remove.  When the window opens choose “Repair”.  Upon completion you should once again be able to create BizTalk projects.

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  • The Case for Complimentary Software Copies

    - by GGBlogger
    As the Geriatric Geek you can understand that I’ve been writing and studying for over 60 years. That means that I’ve seen insane changes in the computer software industry. I’ve made the joke that I get a new college education every 6 months or so. Of course that’s an exaggeration but it doesn’t make the feeling go away. I have a long standing and strong relationship with Microsoft so I’m armed with virtually every tool they make. It also means that I have access to tons of training material. But here’s the rub… Last year I started a definitive read of Professional Visual Basic 2008. The purpose was to fill in holes in my understanding of various things. I’m currently on page 1119 of some 1400 pages. During this sojourn I’ve decided that the future is web related which is to say that the future of “thick client” applications running as Windows applications is likely to slowly disappear. To that end I’ve taken a side trip or two into the world of ASP (including XML), Silverlight and cloud development. After carefully avoiding (that’s tongue in cheek) XML for years I finally had to bite the bullet, so to speak, and start learning XML in earnest. The most recent result of that was trail downloads of Altova’s MissionKit 2010 for Software Architects and Liquid Technologies Liquid XML Studio Developer Edition. These are both beautiful products and I want to learn them and write about them. Now comes the rub… While 30 day evaluations are generous in allowing casual users to assess these technologies for purchase they are NOT long enough to allow an author to evaluate, learn and ultimately write about them. Even if I devoted the full 30 days to learning, using and writing about say Altova’s suite I wouldn’t have enough time. Liquid XML may be a little easier to learn (one product as opposed to 8).  Add to that the fact that I frequently get sidetracked to add to my kit and it really blows out. It can be extremely frustrating when I’ve devoted hours to a project and suddenly discover that to complete it I will either need to purchase a license or abandon the project. Since my life blood does not depend on the product I end up abandoning the project and moving on. So to the folks from whom I request complimentary copies… I guarantee that if I convert your product to doing paid development work I will purchase a license to do that but as long as I am using your product to study for the purpose of writing samples, teaching use or otherwise promoting your product to other paying customers I will ask that you give me a license so that I can do that without facing the dread expiration of a 30 day trial.

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  • New Company Website

    - by Liam McLennan
    For a long time now my company website has been showing its age. It was a dot net nuke monstrosity. Today I have deployed a new website for my company. I hope that it reflects my commitment to quality and minimalism. Please have a look and let me know what you think.

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  • Parallel Computing in .Net 4.0

    - by kaleidoscope
    Technorati Tags: Ram,Parallel Computing in .Net 4.0 Parallel computing is the simultaneous use of multiple compute resources to solve a computational problem: To be run using multiple CPUs A problem is broken into discrete parts that can be solved concurrently Each part is further broken down to a series of instructions Instructions from each part execute simultaneously on different CPUs Parallel Extensions in .NET 4.0 provides a set of libraries and tools to achieve the above mentioned objectives. This supports two paradigms of parallel computing Data Parallelism – This refers to dividing the data across multiple processors for parallel execution.e.g we are processing an array of 1000 elements we can distribute the data between two processors say 500 each. This is supported by the Parallel LINQ (PLINQ) in .NET 4.0 Task Parallelism – This breaks down the program into multiple tasks which can be parallelized and are executed on different processors. This is supported by Task Parallel Library (TPL) in .NET 4.0 A high level view is shown below:

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  • New features for Expression Blend 4 Release Candidate

    - by kaleidoscope
    With Microsoft Expression Blend 4, you can create websites and applications based on Microsoft Silverlight 3 and Microsoft Silverlight 4, and desktop applications based on Windows Presentation Foundation (WPF) 3.5 with Service Pack 1 (SP1) and WPF4. Expression Blend provides new support for prototyping, interactivity through behaviors, special Silverlight functionality, and on-the-fly sample data generation. Expression Blend includes new behaviors that are quickly and easily configured Expression Blend offers new sample data, behaviors, and features of project templates to support the Model-View-ViewModel (MVVM) pattern The MVVM pattern is a way to structure a Silverlight or WPF application so that user interface (UI) objects are as decoupled as possible from the application's data and behavior. This makes it easier for design tasks and development tasks to be performed independently and without breaking each other. Essentially, your UI is the View. You bind objects in the View to properties and commands of the ViewModel, and the View can also call methods on the ViewModel. Compatible with Silverlight 3 and WPF 3.5 with Service Pack 1 (SP1) Interoperate able with Visual Studio. Included New Shapes: The Assets panel in Expression Blend contains a new Shapes category, including presets for the easy creation of arcs, arrows, callouts, and polygons. New Controls: Expression Blend has tooling support for the RichTextBox control in Silverlight. XAML cleanliness :Expression Blend generates less XAML with respect to animations and animation-related properties. MVVM project template: Expression Blend includes a new project template that offers a basic starting point for Model-View-ViewModel pattern applications. Run project with CTRL+F5:To improve consistency with Visual Studio, you can now invoke the Run Project command by pressing either CTRL+F5 or F5 Technorati Tags: Rituraj,Features of Expression Blend4 RC

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  • Applications: The mathematics of movement, Part 1

    - by TechTwaddle
    Before you continue reading this post, a suggestion; if you haven’t read “Programming Windows Phone 7 Series” by Charles Petzold, go read it. Now. If you find 150+ pages a little too long, at least go through Chapter 5, Principles of Movement, especially the section “A Brief Review of Vectors”. This post is largely inspired from this chapter. At this point I assume you know what vectors are, how they are represented using the pair (x, y), what a unit vector is, and given a vector how you would normalize the vector to get a unit vector. Our task in this post is simple, a marble is drawn at a point on the screen, the user clicks at a random point on the device, say (destX, destY), and our program makes the marble move towards that point and stop when it is reached. The tricky part of this task is the word “towards”, it adds a direction to our problem. Making a marble bounce around the screen is simple, all you have to do is keep incrementing the X and Y co-ordinates by a certain amount and handle the boundary conditions. Here, however, we need to find out exactly how to increment the X and Y values, so that the marble appears to move towards the point where the user clicked. And this is where vectors can be so helpful. The code I’ll show you here is not ideal, we’ll be working with C# on Windows Mobile 6.x, so there is no built-in vector class that I can use, though I could have written one and done all the math inside the class. I think it is trivial to the actual problem that we are trying to solve and can be done pretty easily once you know what’s going on behind the scenes. In other words, this is an excuse for me being lazy. The first approach, uses the function Atan2() to solve the “towards” part of the problem. Atan2() takes a point (x, y) as input, Atan2(y, x), note that y goes first, and then it returns an angle in radians. What angle you ask. Imagine a line from the origin (0, 0), to the point (x, y). The angle which Atan2 returns is the angle the positive X-axis makes with that line, measured clockwise. The figure below makes it clear, wiki has good details about Atan2(), give it a read. The pair (x, y) also denotes a vector. A vector whose magnitude is the length of that line, which is Sqrt(x*x + y*y), and a direction ?, as measured from positive X axis clockwise. If you’ve read that chapter from Charles Petzold’s book, this much should be clear. Now Sine and Cosine of the angle ? are special. Cosine(?) divides x by the vectors length (adjacent by hypotenuse), thus giving us a unit vector along the X direction. And Sine(?) divides y by the vectors length (opposite by hypotenuse), thus giving us a unit vector along the Y direction. Therefore the vector represented by the pair (cos(?), sin(?)), is the unit vector (or normalization) of the vector (x, y). This unit vector has a length of 1 (remember sin2(?) + cos2(?) = 1 ?), and a direction which is the same as vector (x, y). Now if I multiply this unit vector by some amount, then I will always get a point which is a certain distance away from the origin, but, more importantly, the point will always be on that line. For example, if I multiply the unit vector with the length of the line, I get the point (x, y). Thus, all we have to do to move the marble towards our destination point, is to multiply the unit vector by a certain amount each time and draw the marble, and the marble will magically move towards the click point. Now time for some code. The application, uses a timer based frame draw method to draw the marble on the screen. The timer is disabled initially and whenever the user clicks on the screen, the timer is enabled. The callback function for the timer follows the standard Update and Draw cycle. private double totLenToTravelSqrd = 0; private double startPosX = 0, startPosY = 0; private double destX = 0, destY = 0; private void Form1_MouseUp(object sender, MouseEventArgs e) {     destX = e.X;     destY = e.Y;     double x = marble1.x - destX;     double y = marble1.y - destY;     //calculate the total length to be travelled     totLenToTravelSqrd = x * x + y * y;     //store the start position of the marble     startPosX = marble1.x;     startPosY = marble1.y;     timer1.Enabled = true; } private void timer1_Tick(object sender, EventArgs e) {     UpdatePosition();     DrawMarble(); } Form1_MouseUp() method is called when ever the user touches and releases the screen. In this function we save the click point in destX and destY, this is the destination point for the marble and we also enable the timer. We store a few more values which we will use in the UpdatePosition() method to detect when the marble has reached the destination and stop the timer. So we store the start position of the marble and the square of the total length to be travelled. I’ll leave out the term ‘sqrd’ when speaking of lengths from now on. The time out interval of the timer is set to 40ms, thus giving us a frame rate of about ~25fps. In the timer callback, we update the marble position and draw the marble. We know what DrawMarble() does, so here, we’ll only look at how UpdatePosition() is implemented; private void UpdatePosition() {     //the vector (x, y)     double x = destX - marble1.x;     double y = destY - marble1.y;     double incrX=0, incrY=0;     double distanceSqrd=0;     double speed = 6;     //distance between destination and current position, before updating marble position     distanceSqrd = x * x + y * y;     double angle = Math.Atan2(y, x);     //Cos and Sin give us the unit vector, 6 is the value we use to magnify the unit vector along the same direction     incrX = speed * Math.Cos(angle);     incrY = speed * Math.Sin(angle);     marble1.x += incrX;     marble1.y += incrY;     //check for bounds     if ((int)marble1.x < MinX + marbleWidth / 2)     {         marble1.x = MinX + marbleWidth / 2;     }     else if ((int)marble1.x > (MaxX - marbleWidth / 2))     {         marble1.x = MaxX - marbleWidth / 2;     }     if ((int)marble1.y < MinY + marbleHeight / 2)     {         marble1.y = MinY + marbleHeight / 2;     }     else if ((int)marble1.y > (MaxY - marbleHeight / 2))     {         marble1.y = MaxY - marbleHeight / 2;     }     //distance between destination and current point, after updating marble position     x = destX - marble1.x;     y = destY - marble1.y;     double newDistanceSqrd = x * x + y * y;     //length from start point to current marble position     x = startPosX - (marble1.x);     y = startPosY - (marble1.y);     double lenTraveledSqrd = x * x + y * y;     //check for end conditions     if ((int)lenTraveledSqrd >= (int)totLenToTravelSqrd)     {         System.Console.WriteLine("Stopping because destination reached");         timer1.Enabled = false;     }     else if (Math.Abs((int)distanceSqrd - (int)newDistanceSqrd) < 4)     {         System.Console.WriteLine("Stopping because no change in Old and New position");         timer1.Enabled = false;     } } Ok, so in this function, first we subtract the current marble position from the destination point to give us a vector. The first three lines of the function construct this vector (x, y). The vector (x, y) has the same length as the line from (marble1.x, marble1.y) to (destX, destY) and is in the direction pointing from (marble1.x, marble1.y) to (destX, destY). Note that marble1.x and marble1.y denote the center point of the marble. Then we use Atan2() to get the angle which this vector makes with the positive X axis and use Cosine() and Sine() of that angle to get the unit vector along that same direction. We multiply this unit vector with 6, to get the values which the position of the marble should be incremented by. This variable, speed, can be experimented with and determines how fast the marble moves towards the destination. After this, we check for bounds to make sure that the marble stays within the screen limits and finally we check for the end condition and stop the timer. The end condition has two parts to it. The first case is the normal case, where the user clicks well inside the screen. Here, we stop when the total length travelled by the marble is greater than or equal to the total length to be travelled. Simple enough. The second case is when the user clicks on the very corners of the screen. Like I said before, the values marble1.x and marble1.y denote the center point of the marble. When the user clicks on the corner, the marble moves towards the point, and after some time tries to go outside of the screen, this is when the bounds checking comes into play and corrects the marble position so that the marble stays inside the screen. In this case the marble will never travel a distance of totLenToTravelSqrd, because of the correction is its position. So here we detect the end condition when there is not much change in marbles position. I use the value 4 in the second condition above. After experimenting with a few values, 4 seemed to work okay. There is a small thing missing in the code above. In the normal case, case 1, when the update method runs for the last time, marble position over shoots the destination point. This happens because the position is incremented in steps (which are not small enough), so in this case too, we should have corrected the marble position, so that the center point of the marble sits exactly on top of the destination point. I’ll add this later and update the post. This has been a pretty long post already, so I’ll leave you with a video of how this program looks while running. Notice in the video that the marble moves like a bot, without any grace what so ever. And that is because the speed of the marble is fixed at 6. In the next post we will see how to make the marble move a little more elegantly. And also, if Atan2(), Sine() and Cosine() are a little too much to digest, we’ll see how to achieve the same effect without using them, in the next to next post maybe. Ciao!

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  • BI Presentation for SharePoint 2010

    - by Leonard Mwangi
    I have uploaded the BI Presentation slideds for SharePoint 2010 that I presented at Kansas City SharePoint Users Group. The slides can be downloaded from http://www.etekglobalinc.com/Portals/0/blogs/Business%20intelligence%20with%20SharePoint%202010.ppt

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  • SSIS Send Mail Task and ForceExecutionValue Error

    - by Kevin Shyr
    I tried to use the "ForcedExecutionValue" on several Send Mail Tasks and log the execution into a ExecValueVariable so that at the end of the package I can log into a table to say whether the data check is successful or not (by determine whether an email was sent out) I set up a Boolean variable that is accessible at the package level, then set up my Send Mail Task as the screenshot below with Boolean as my ForcedExecutionValueType.  When I run the package, I got the error described below. Just to make sure this is not another issue of SSIS having with Boolean type ( you also can't set variable value from xp_cmdshell of type Boolean), I used variables of types String, Int32, DateTime with the corresponding ForcedExecutionValueType.  The only way to get around this error, was to set my variable to type Object, but then when you try to get the value out later, the Object is null. I didn't spend enough time on this to see whether it's really a bug in SSIS or not, or is this just how Send Mail Task works.  Just want to log the error and will circle back on this later to narrow down the issue some more.  In the meantime, please share if you have run into the same problem.  The current workaround is to attach a script task at the end. Also, need to note 2 existing limitation: Data check needs to be done serially because every check needs to be inner join to a master table.  The master table has all the data in a single XML column and hence need to be retrieved with XQuery (a fundamental design flaw that needs to be changed) The next iteration will be to change this design into a FOR loop and pull out the checking query from a table somewhere with all the info needed for email task, but is being put to the back of the priority. Error Message: Error: 0xC001F009 at CountCheckBetweenODSAndCleanSchema: The type of the value being assigned to variable "User::WasErrorEmailEverSent" differs from the current variable type. Variables may not change type during execution. Variable types are strict, except for variables of type Object. Error: 0xC0019001 at Send Mail Task on count mismatch: The wrapper was unable to set the value of the variable specified in the ExecutionValueVariable property.   Screenshot of my Send Mail Task setup:

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  • Attaching a Command to the WP7 Application Bar.

    - by mbcrump
    One of the biggest problems that I’ve seen with people creating WP7 applications is how do you bind the application bar to a Relay Command. If your using MVVM then this is particular important. Let’s examine the code that one might add to start with.  <phone:PhoneApplicationPage.ApplicationBar> <shell:ApplicationBar IsVisible="True" IsMenuEnabled="True"> <shell:ApplicationBarIconButton x:Name="appbar_button1" IconUri="/icons/appbar.questionmark.rest.png" Text="About"> <i:Interaction.Triggers> <i:EventTrigger EventName="Click"> <GalaSoft_MvvmLight_Command:EventToCommand Command="{Binding DisplayAbout, Mode=OneWay}" /> </i:EventTrigger> </i:Interaction.Triggers> </shell:ApplicationBarIconButton> <shell:ApplicationBar.MenuItems> <shell:ApplicationBarMenuItem x:Name="menuItem1" Text="MenuItem 1"></shell:ApplicationBarMenuItem> <shell:ApplicationBarMenuItem x:Name="menuItem2" Text="MenuItem 2"></shell:ApplicationBarMenuItem> </shell:ApplicationBar.MenuItems> </shell:ApplicationBar> </phone:PhoneApplicationPage.ApplicationBar> Everything looks right. But we quickly notice that we have a squiggly line under our Interaction.Triggers. The problem is that the object is not a FrameworkObject. This same code would have worked perfect if this were a normal button. OK. Point has been proved. Let’s make the ApplicationBar support Commands. So, go ahead and create a new project using MVVM Light. If you want to check out the source and work along side this tutorial then click here.  7 Easy Steps to have binding on the Application Bar using MVVM Light (I might add that you don’t have to use MVVM Light to get this functionality, I just prefer it.) 1) Download MVVM Light if you don’t already have it and install the project templates. It is available at http://mvvmlight.codeplex.com/. 2) Click File-New Project and navigate to Silverlight for Windows Phone. Make sure you use the MVVM Light (WP7) Template. 3) Now that we have our project setup and ready to go let’s download a wrapper created by Nicolas Humann here, it is called Phone7.Fx. After you download it then extract it somewhere that you can find it. This wrapper will make our application bar/menu item bindable. 4) Right click References inside your WP7 project and add the .dll file to your project. 5) In your MainPage.xaml you will need to add the proper namespace to it. Don’t forget to build your project afterwards. xmlns:Preview="clr-namespace:Phone7.Fx.Preview;assembly=Phone7.Fx.Preview" 6) Now you can add the BindableAppBar to your MainPage.xaml with a few lines of code.  <Preview:BindableApplicationBar x:Name="AppBar" BarOpacity="1.0" > <Preview:BindableApplicationBarIconButton Command="{Binding DisplayAbout}" IconUri="/icons/appbar.questionmark.rest.png" Text="About" /> <Preview:BindableApplicationBar.MenuItems> <Preview:BindableApplicationBarMenuItem Text="Settings" Command="{Binding InputBox}" /> </Preview:BindableApplicationBar.MenuItems> </Preview:BindableApplicationBar> So your final MainPage.xaml will look similar to this: NOTE: The AppBar will be located inside of the Grid using this wrapper.   <!--LayoutRoot contains the root grid where all other page content is placed--> <Grid x:Name="LayoutRoot" Background="Transparent"> <Grid.RowDefinitions> <RowDefinition Height="Auto" /> <RowDefinition Height="*" /> </Grid.RowDefinitions> <!--TitlePanel contains the name of the application and page title--> <StackPanel x:Name="TitlePanel" Grid.Row="0" Margin="24,24,0,12"> <TextBlock x:Name="ApplicationTitle" Text="{Binding ApplicationTitle}" Style="{StaticResource PhoneTextNormalStyle}" /> <TextBlock x:Name="PageTitle" Text="{Binding PageName}" Margin="-3,-8,0,0" Style="{StaticResource PhoneTextTitle1Style}" /> </StackPanel> <!--ContentPanel - place additional content here--> <Grid x:Name="ContentGrid" Grid.Row="1"> <TextBlock Text="{Binding Welcome}" Style="{StaticResource PhoneTextNormalStyle}" HorizontalAlignment="Center" VerticalAlignment="Center" FontSize="40" /> </Grid> <Preview:BindableApplicationBar x:Name="AppBar" BarOpacity="1.0" > <Preview:BindableApplicationBarIconButton Command="{Binding DisplayAbout}" IconUri="/icons/appbar.questionmark.rest.png" Text="About" /> <Preview:BindableApplicationBar.MenuItems> <Preview:BindableApplicationBarMenuItem Text="Settings" Command="{Binding InputBox}" /> </Preview:BindableApplicationBar.MenuItems> </Preview:BindableApplicationBar> </Grid> 7) Let’s go ahead and create the RelayCommands and write them up to a MessageBox by editing our MainViewModel.cs file. public class MainViewModel : ViewModelBase { public string ApplicationTitle { get { return "MVVM LIGHT"; } } public string PageName { get { return "My page:"; } } public string Welcome { get { return "Welcome to MVVM Light"; } } public RelayCommand DisplayAbout { get; private set; } public RelayCommand InputBox { get; private set; } /// <summary> /// Initializes a new instance of the MainViewModel class. /// </summary> public MainViewModel() { if (IsInDesignMode) { // Code runs in Blend --> create design time data. } else { DisplayAbout = new RelayCommand(() => { MessageBox.Show("About box called!"); }); InputBox = new RelayCommand(() => { MessageBox.Show("settings button called"); }); } } If you run the project now you should get something similar to this (notice the AppBar at the bottom):  Now if you hit the question mark then you will get the following MessageBox: The MenuItem works as well so for Settings: As you can see, its pretty easy to add a Command to the ApplicationBar/MenuItem. If you want to look through the full source code then click here.   Subscribe to my feed

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  • Why do we (really) program to interfaces?

    - by Kyle Burns
    One of the earliest lessons I was taught in Enterprise development was "always program against an interface".  This was back in the VB6 days and I quickly learned that no code would be allowed to move to the QA server unless my business objects and data access objects each are defined as an interface and have a matching implementation class.  Why?  "It's more reusable" was one answer.  "It doesn't tie you to a specific implementation" a slightly more knowing answer.  And let's not forget the discussion ending "it's a standard".  The problem with these responses was that senior people didn't really understand the reason we were doing the things we were doing and because of that, we were entirely unable to realize the intent behind the practice - we simply used interfaces and had a bunch of extra code to maintain to show for it. It wasn't until a few years later that I finally heard the term "Inversion of Control".  Simply put, "Inversion of Control" takes the creation of objects that used to be within the control (and therefore a responsibility of) of your component and moves it to some outside force.  For example, consider the following code which follows the old "always program against an interface" rule in the manner of many corporate development shops: 1: ICatalog catalog = new Catalog(); 2: Category[] categories = catalog.GetCategories(); In this example, I met the requirement of the rule by declaring the variable as ICatalog, but I didn't hit "it doesn't tie you to a specific implementation" because I explicitly created an instance of the concrete Catalog object.  If I want to test the functionality of the code I just wrote I have to have an environment in which Catalog can be created along with any of the resources upon which it depends (e.g. configuration files, database connections, etc) in order to test my functionality.  That's a lot of setup work and one of the things that I think ultimately discourages real buy-in of unit testing in many development shops. So how do I test my code without needing Catalog to work?  A very primitive approach I've seen is to change the line the instantiates catalog to read: 1: ICatalog catalog = new FakeCatalog();   once the test is run and passes, the code is switched back to the real thing.  This obviously poses a huge risk for introducing test code into production and in my opinion is worse than just keeping the dependency and its associated setup work.  Another popular approach is to make use of Factory methods which use an object whose "job" is to know how to obtain a valid instance of the object.  Using this approach, the code may look something like this: 1: ICatalog catalog = CatalogFactory.GetCatalog();   The code inside the factory is responsible for deciding "what kind" of catalog is needed.  This is a far better approach than the previous one, but it does make projects grow considerably because now in addition to the interface, the real implementation, and the fake implementation(s) for testing you have added a minimum of one factory (or at least a factory method) for each of your interfaces.  Once again, developers say "that's too complicated and has me writing a bunch of useless code" and quietly slip back into just creating a new Catalog and chalking any test failures up to "it will probably work on the server". This is where software intended specifically to facilitate Inversion of Control comes into play.  There are many libraries that take on the Inversion of Control responsibilities in .Net and most of them have many pros and cons.  From this point forward I'll discuss concepts from the standpoint of the Unity framework produced by Microsoft's Patterns and Practices team.  I'm primarily focusing on this library because it questions about it inspired this posting. At Unity's core and that of most any IoC framework is a catalog or registry of components.  This registry can be configured either through code or using the application's configuration file and in the most simple terms says "interface X maps to concrete implementation Y".  It can get much more complicated, but I want to keep things at the "what does it do" level instead of "how does it do it".  The object that exposes most of the Unity functionality is the UnityContainer.  This object exposes methods to configure the catalog as well as the Resolve<T> method which is used to obtain an instance of the type represented by T.  When using the Resolve<T> method, Unity does not necessarily have to just "new up" the requested object, but also can track dependencies of that object and ensure that the entire dependency chain is satisfied. There are three basic ways that I have seen Unity used within projects.  Those are through classes directly using the Unity container, classes requiring injection of dependencies, and classes making use of the Service Locator pattern. The first usage of Unity is when classes are aware of the Unity container and directly call its Resolve method whenever they need the services advertised by an interface.  The up side of this approach is that IoC is utilized, but the down side is that every class has to be aware that Unity is being used and tied directly to that implementation. Many developers don't like the idea of as close a tie to specific IoC implementation as is represented by using Unity within all of your classes and for the most part I agree that this isn't a good idea.  As an alternative, classes can be designed for Dependency Injection.  Dependency Injection is where a force outside the class itself manipulates the object to provide implementations of the interfaces that the class needs to interact with the outside world.  This is typically done either through constructor injection where the object has a constructor that accepts an instance of each interface it requires or through property setters accepting the service providers.  When using dependency, I lean toward the use of constructor injection because I view the constructor as being a much better way to "discover" what is required for the instance to be ready for use.  During resolution, Unity looks for an injection constructor and will attempt to resolve instances of each interface required by the constructor, throwing an exception of unable to meet the advertised needs of the class.  The up side of this approach is that the needs of the class are very clearly advertised and the class is unaware of which IoC container (if any) is being used.  The down side of this approach is that you're required to maintain the objects passed to the constructor as instance variables throughout the life of your object and that objects which coordinate with many external services require a lot of additional constructor arguments (this gets ugly and may indicate a need for refactoring). The final way that I've seen and used Unity is to make use of the ServiceLocator pattern, of which the Patterns and Practices team has also provided a Unity-compatible implementation.  When using the ServiceLocator, your class calls ServiceLocator.Retrieve in places where it would have called Resolve on the Unity container.  Like using Unity directly, it does tie you directly to the ServiceLocator implementation and makes your code aware that dependency injection is taking place, but it does have the up side of giving you the freedom to swap out the underlying IoC container if necessary.  I'm not hugely concerned with hiding IoC entirely from the class (I view this as a "nice to have"), so the single biggest problem that I see with the ServiceLocator approach is that it provides no way to proactively advertise needs in the way that constructor injection does, allowing more opportunity for difficult to track runtime errors. This blog entry has not been intended in any way to be a definitive work on IoC, but rather as something to spur thought about why we program to interfaces and some ways to reach the intended value of the practice instead of having it just complicate your code.  I hope that it helps somebody begin or continue a journey away from being a "Cargo Cult Programmer".

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  • Defaulting the HLSL Vertex and Pixel Shader Levels to Feature Level 9_1 in VS 2012

    - by Michael B. McLaughlin
    I love Visual Studio 2012. But this is not a post about that. This is a post about tweaking one particular parameter that I’ve found a bit annoying. Disclaimer: You will be modifying important MSBuild files. If you screw up you will break your build tools. And maybe your computer will catch fire. I’m not responsible. No warranties or guaranties of any sort. This info is provided “as is”. By default, if you add a new vertex shader or pixel shader item to a project, it will be set to build with shader profile 4.0_level_9_3. If you need 9_3 functionality, this is all well and good. But (especially for Windows Store apps) you really want to target the lowest shader profile possible so that your game will run on as many computers as possible. So it’s a good idea to default to 9_1. To do this you could add in new HLSL files via “Add->New Item->Visual C++->HLSL->______ Shader File (.hlsl)” and then edit the shader files’ properties to set them manually to use 9_1 via “Properties->HLSL Compiler->General->Shader Model”. This is fine unless you forget to do this once and then submit your game with 9_3 shaders instead of 9_1 shaders to the Windows Store or to some other game store. Then you’d wind up with either rejection or angry “this doesn’t work on my computer! ripoff!” messages. There’s another option though. In “Program Files (x86)\Microsoft Visual Studio 11.0\Common7\IDE\ItemTemplates\VC\HLSL\1033\VertexShader” (note the path might vary slightly for you if you are using a 32-bit system or have a non-ENU version of Visual Studio 2012) you will find a “VertexShader.vstemplate” file. If you open this file in a text editor (e.g. Notepad++), then inside the CustomParameters tag within the TemplateContent tag you should see a CustomParameter tag for the ShaderType, i.e.: <CustomParameter Name="$ShaderType$" Value="Vertex"/> On a new line, we are going to add another CustomParameter tag to the CustomParameters tag. It will look like this: <CustomParameter Name="$ShaderModel$" Value="4.0_level_9_1"/> such that we now have:     <CustomParameters>       <CustomParameter Name="$ShaderType$" Value="Vertex"/>       <CustomParameter Name="$ShaderModel$" Value="4.0_level_9_1"/>     </CustomParameters> You can then save the file (you will need to be an Administrator or have Administrator access). Back in the 1033 directory (or whatever the number is for your language), go into the “PixelShader” directory. Edit the “PixelShader.vstemplate” file and make the same change (note that this time $ShaderType$ is “Pixel” not “Vertex”; you shouldn’t be changing that line anyway, but if you were to just copy and replace the above four lines then you will wind up creating pixel shaders that the HLSL compiler would try to compile as vertex shaders, with all sort of weird errors as a result). Once you’ve added the $ShaderModel$ line to “PixelShader.vstemplate” and have saved it, everything should be done. Since Feature Level 9_1 and 9_3 don’t support any of the other shader types, those are set to default to their appropriate minimums already (Compute and Geometry are set to “4.0” and Domain and Hull are set to “5.0”, which are their respective minimums (though not all 4.0 cards support Compute shaders; they were an optional feature added with DirectX 10.1 and only became required for DirectX 11 hardware). In case you are wondering where these magic values come from, you can find them all in the “fxc.xml” file in the “\Program Files (x86)\MSBuild\Microsoft.CPP\v4.0\V110\1033” directory (or whatever your language number is; 1033 is ENU and various other product languages have their own respective numbers (see: http://msdn.microsoft.com/en-us/goglobal/bb964664.aspx ) such that Japanese is 1041 (for example), though for all I know MSBuild tasks might be 1033 for everyone). If, like me, you installed VS 2012 to a drive other than the C:\ drive, you will find the vstemplate files in the drive to which you installed VS 2012 (D:\ in my case) but you will find the fxc.xml file on the C:\ drive. You should not edit fxc.xml. You will almost definitely break things by doing that; it’s just something you can look through to see all the other options that the FXC task takes such that you could, if needed, add further CustomParameter tags if you wanted to default to other supported options. I haven’t tried any others though so I don’t have any advice on how to set them.

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  • Using LINQ to Twitter OAuth with Windows 8

    - by Joe Mayo
    In previous posts, I explained how to use LINQ to Twitter with Windows 8, but the example was a Twitter Search, which didn’t require authentication. Much of the Twitter API requires authentication, so this post will explain how you can perform OAuth authentication with LINQ to Twitter in a Windows 8 Metro-style application. Getting Started I have earlier posts on how to create a Windows 8 app and add pages, so I’ll assume it isn’t necessary to repeat here. One difference is that I’m using Visual Studio 2012 RC and some of the terminology and/or library code might be slightly different.  Here are steps to get started: Create a new Windows metro style app, selecting the Blank App project template. Create a new Basic Page and name it OAuth.xaml.  Note: You’ll receive a prompt window for adding files and you should click Yes because those files are necessary for this demo. Add a new Basic Page named TweetPage.xaml. Open App.xaml.cs and change !rootFrame.Navigate(typeof(MainPage)) to !rootFrame.Navigate(typeof(TweetPage)). Now that the project is set up you’ll see the reason why authentication is required by setting up the TweetPage. Setting Up to Tweet a Status In this section, I’ll show you how to set up the XAML and code-behind for a tweet.  The tweet logic will check to see if the user is authenticated before performing the tweet. To tweet, I put a TextBox and Button on the XAML page. The following code omits most of the page, concentrating primarily on the elements of interest in this post: <StackPanel Grid.Row="1"> <TextBox Name="TweetTextBox" Margin="15" /> <Button Name="TweetButton" Content="Tweet" Click="TweetButton_Click" Margin="15,0" /> </StackPanel> Given the UI above, the user types the message they want to tweet, and taps Tweet. This invokes TweetButton_Click, which checks to see if the user is authenticated.  If the user is not authenticated, the app navigates to the OAuth page.  If they are authenticated, LINQ to Twitter does an UpdateStatus to post the user’s tweet.  Here’s the TweetButton_Click implementation: void TweetButton_Click(object sender, RoutedEventArgs e) { PinAuthorizer auth = null; if (SuspensionManager.SessionState.ContainsKey("Authorizer")) { auth = SuspensionManager.SessionState["Authorizer"] as PinAuthorizer; } if (auth == null || !auth.IsAuthorized) { Frame.Navigate(typeof(OAuthPage)); return; } var twitterCtx = new TwitterContext(auth); Status tweet = twitterCtx.UpdateStatus(TweetTextBox.Text); new MessageDialog(tweet.Text, "Successful Tweet").ShowAsync(); } For authentication, this app uses PinAuthorizer, one of several authorizers available in the LINQ to Twitter library. I’ll explain how PinAuthorizer works in the next section. What’s important here is that LINQ to Twitter needs an authorizer to post a Tweet. The code above checks to see if a valid authorizer is available. To do this, it uses the SuspensionManager class, which is part of the code generated earlier when creating OAuthPage.xaml. The SessionState property is a Dictionary<string, object> and I’m using the Authorizer key to store the PinAuthorizer.  If the user previously authorized during this session, the code reads the PinAuthorizer instance from SessionState and assigns it to the auth variable. If the user is authorized, auth would not be null and IsAuthorized would be true. Otherwise, the app navigates the user to OAuthPage.xaml, which I’ll discuss in more depth in the next section. When the user is authorized, the code passes the authorizer, auth, to the TwitterContext constructor. LINQ to Twitter uses the auth instance to build OAuth signatures for each interaction with Twitter.  You no longer need to write any more code to make this happen. The code above accepts the tweet just posted in the Status instance, tweet, and displays a message with the text to confirm success to the user. You can pull the PinAuthorizer instance from SessionState, instantiate your TwitterContext, and use it as you need. Just remember to make sure you have a valid authorizer, like the code above. As shown earlier, the code navigates to OAuthPage.xaml when a valid authorizer isn’t available. The next section shows how to perform the authorization upon arrival at OAuthPage.xaml. Doing the OAuth Dance This section shows how to authenticate with LINQ to Twitter’s built-in OAuth support. From the user perspective, they must be navigated to the Twitter authentication page, add credentials, be navigated to a Pin number page, and then enter that Pin in the Windows 8 application. The following XAML shows the relevant elements that the user will interact with during this process. <StackPanel Grid.Row="2"> <WebView x:Name="OAuthWebBrowser" HorizontalAlignment="Left" Height="400" Margin="15" VerticalAlignment="Top" Width="700" /> <TextBlock Text="Please perform OAuth process (above), enter Pin (below) when ready, and tap Authenticate:" Margin="15,15,15,5" /> <TextBox Name="PinTextBox" Margin="15,0,15,15" Width="432" HorizontalAlignment="Left" IsEnabled="False" /> <Button Name="AuthenticatePinButton" Content="Authenticate" Margin="15" IsEnabled="False" Click="AuthenticatePinButton_Click" /> </StackPanel> The WebView in the code above is what allows the user to see the Twitter authentication page. The TextBox is for entering the Pin, and the Button invokes code that will take the Pin and allow LINQ to Twitter to complete the authentication process. As you can see, there are several steps to OAuth authentication, but LINQ to Twitter tries to minimize the amount of code you have to write. The two important parts of the code to make this happen are the part that starts the authentication process and the part that completes the authentication process. The following code, from OAuthPage.xaml.cs, shows a couple events that are instrumental in making this process happen: public OAuthPage() { this.InitializeComponent(); this.Loaded += OAuthPage_Loaded; OAuthWebBrowser.LoadCompleted += OAuthWebBrowser_LoadCompleted; } The OAuthWebBrowser_LoadCompleted event handler enables UI controls when the browser is done loading – notice that the TextBox and Button in the previous XAML have their IsEnabled attributes set to False. When the Page.Loaded event is invoked, the OAuthPage_Loaded handler starts the OAuth process, shown here: void OAuthPage_Loaded(object sender, RoutedEventArgs e) { auth = new PinAuthorizer { Credentials = new InMemoryCredentials { ConsumerKey = "", ConsumerSecret = "" }, UseCompression = true, GoToTwitterAuthorization = pageLink => Dispatcher.RunAsync(CoreDispatcherPriority.Normal, () => OAuthWebBrowser.Navigate(new Uri(pageLink, UriKind.Absolute))) }; auth.BeginAuthorize(resp => Dispatcher.RunAsync(CoreDispatcherPriority.Normal, () => { switch (resp.Status) { case TwitterErrorStatus.Success: break; case TwitterErrorStatus.RequestProcessingException: case TwitterErrorStatus.TwitterApiError: new MessageDialog(resp.Error.ToString(), resp.Message).ShowAsync(); break; } })); } The PinAuthorizer, auth, a field of this class instantiated in the code above, assigns keys to the Credentials property. These are credentials that come from registering an application with Twitter, explained in the LINQ to Twitter documentation, Securing Your Applications. Notice how I use Dispatcher.RunAsync to marshal the web browser navigation back onto the UI thread. Internally, LINQ to Twitter invokes the lambda expression assigned to GoToTwitterAuthorization when starting the OAuth process.  In this case, we want the WebView control to navigate to the Twitter authentication page, which is defined with a default URL in LINQ to Twitter and passed to the GoToTwitterAuthorization lambda as pageLink. Then you need to start the authorization process by calling BeginAuthorize. This starts the OAuth dance, running asynchronously.  LINQ to Twitter invokes the callback assigned to the BeginAuthorize parameter, allowing you to take whatever action you need, based on the Status of the response, resp. As mentioned earlier, this is where the user performs the authentication process, enters the Pin, and clicks authenticate. The handler for authenticate completes the process and saves the authorizer for subsequent use by the application, as shown below: void AuthenticatePinButton_Click(object sender, RoutedEventArgs e) { auth.CompleteAuthorize( PinTextBox.Text, completeResp => Dispatcher.RunAsync(CoreDispatcherPriority.Normal, () => { switch (completeResp.Status) { case TwitterErrorStatus.Success: SuspensionManager.SessionState["Authorizer"] = auth; Frame.Navigate(typeof(TweetPage)); break; case TwitterErrorStatus.RequestProcessingException: case TwitterErrorStatus.TwitterApiError: new MessageDialog(completeResp.Error.ToString(), completeResp.Message).ShowAsync(); break; } })); } The PinAuthorizer CompleteAuthorize method takes two parameters: Pin and callback. The Pin is from what the user entered in the TextBox prior to clicking the Authenticate button that invoked this method. The callback handles the response from completing the OAuth process. The completeResp holds information about the results of the operation, indicated by a Status property of type TwitterErrorStatus. On success, the code assigns auth to SessionState. You might remember SessionState from the previous description of TweetPage – this is where the valid authorizer comes from. After saving the authorizer, the code navigates the user back to TweetPage, where they can type in a message, click the Tweet button, and observe that they have successfully tweeted. Summary You’ve seen how to get started with using LINQ to Twitter in a Metro-style application. The generated code contained a SuspensionManager class with way to manage information across multiple pages via its SessionState property. You also saw how LINQ to Twitter performs authorization in two steps of starting the process and completing the process when the user provides a Pin number. Remember to marshal callback thread back onto the UI – you saw earlier how to use Dispatcher.RunAsync to accomplish this. There were a few steps in the process, but LINQ to Twitter did minimize the amount of code you needed to write to make it happen. You can download the MetroOAuthDemo.zip sample on the LINQ to Twitter Samples Page.   @JoeMayo

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  • Glume cu chelneri

    - by interesante
    La un mic restaurant, in luna decembrie:- Chelner, ce ai rece in acest moment?- Picioarele, domnule.Distreaza-te si cu alte lucruri amuzante de pe jurnalul meu haios.La un restaurant de lux, vine controlul de la Sanepid.Fac ei controlul si constata ca totul era o.k.Multumiti,din partea patronului de local,primesc si un pranz.Vine chelnerul,ii intreaba ce vin doresc sa serveasca,le aduce vinul,scoate dopul de pluta,le toarna in pahare si, ca la un local care se respecta,acesta scoase o lingurita de la pieptul sacoului si curata cu grija bucatelele de pluta din paharele mesenilor. Dupa ce inspectorii servira masa, il chemara pe chelner sa-i multumeasca si-l intrebara: - Nu va suparati! De ce purtati snur la slit? - Igiena inainte de toate! Cand ne ducem la buda, ca sa nu mai punem mana, tragem de snur si gata! - Aha! Si cum o bagati la loc? - Cu lingurita!

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  • Agilist, Heal Thyself!

    - by Dylan Smith
    I’ve been meaning to blog about a great experience I had earlier in the year at Prairie Dev Con Calgary.  Myself and Steve Rogalsky did a session that we called “Agilist, Heal Thyself!”.  We used a format that was new to me, but that Steve had seen used at another conference.  What we did was start by asking the audience to give us a list of challenges they had had when adopting agile.  We wrote them all down, then had everybody vote on the most interesting ones.  Then we split into two groups, and each group was assigned one of the agile challenges.  We had 20 minutes to discuss the challenge, and suggest solutions or approaches to improve things.  At the end of the 20 minutes, each of the groups gave a brief summary of their discussion and learning's, then we mixed up the groups and repeated with another 2 challenges. The 2 groups I was part of had some really interesting discussions, and suggestions: Unfinished Stories at the end of Sprints The first agile challenge we tackled, was something that every single Scrum team I have worked with has struggled with.  What happens when you get to the end of a Sprint, and there are some stories that are only partially completed.  The team in question was getting very de-moralized as they felt that every Sprint was a failure as they never had a set of fully completed stories. How do you avoid this? and/or what do you do when it happens? There were 2 pieces of advice that were well received: 1. Try to bring stories to completion before starting new ones.  This is advice I give all my Scrum teams.  If you have a 3-week sprint, what happens all too often is you get to the end of week 2, and a lot of stories are almost done; but almost none are completely done.  This is a Bad Thing.  I encourage the teams I work with to only start a new story as a very last resort.  If you finish your task look at the stories in progress and see if there’s anything you can do to help before moving onto a new story.  In the daily standup, put a focus on seeing what stories got completed yesterday, if a few days go by with none getting completed, be sure this fact is visible to the team and do something about it.  Something I’ve been doing recently is introducing WIP (Work In Progress) limits while using Scrum.  My current team has 2-week sprints, and we usually have about a dozen or stories in a sprint.  We instituted a WIP limit of 4 stories.  If 4 stories have been started but not finished then nobody is allowed to start new stories.  This made it obvious very quickly that our QA tasks were our bottleneck (we have 4 devs, but only 1.5 testers).  The WIP limit forced the developers to start to pickup QA tasks before moving onto the next dev tasks, and we ended our sprints with many more stories completely finished than we did before introducing WIP limits. 2. Rather than using time-boxed sprints, why not just do away with them altogether and go to a continuous flow type approach like KanBan.  Limit WIP to keep things under control, but don’t have a fixed time box at the end of which all tasks are supposed to be done.  This eliminates the problem almost entirely.  At some points in the project (releases) you need to be able to burn down all the half finished stories to get a stable release build, but this probably occurs less often than every sprint, and there are alternative approaches to achieve it using branching strategies rather than forcing your team to try to get to Zero WIP every 2-weeks (e.g. when you are ready for a release, create a new branch for any new stories, but finish all existing stories in the current branch and release it). Trying to Introduce Agile into a team with previous Bad Agile Experiences One of the agile adoption challenges somebody described, was he was in a leadership role on a team he had recently joined – lets call him Dave.  This team was currently very waterfall in their ALM process, but they were about to start on a new green-field project.  Dave wanted to use this new project as an opportunity to do things the “right way”, using an Agile methodology like Scrum, adopting TDD, automated builds, proper branching strategies, etc.  The problem he was facing is everybody else on the team had previously gone through an “Agile Adoption” that was a horrible failure.  Dave blamed this failure on the consultant brought in previously to lead this agile transition, but regardless of the reason, the team had very negative feelings towards agile, and was very resistant to trying it out again.  Dave possibly had the authority to try to force the team to adopt Agile practices, but we all know that doesn’t work very well.  What was Dave to do? Ultimately, the best advice was to question *why* did Dave want to adopt all these various practices. Rather than trying to convince his team that these were the “right way” to run a dev project, and trying to do a Big Bang approach to introducing change.  He would be better served by identifying problems the team currently faces, have a discussion with the team to get everybody to agree that specific problems existed, then have an open discussion about ways to address those problems.  This way Dave could incrementally introduce agile practices, and he doesn’t even need to identify them as “agile” practices if he doesn’t want to.  For example, when we discussed with Dave, he said probably the teams biggest problem was long periods without feedback from users, then finding out too late that the software is not going to meet their needs.  Rather than Dave jumping right to introducing Scrum and all it entails, it would be easier to get buy-in from team if he framed it as a discussion of existing problems, and brainstorming possible solutions.  And possibly most importantly, don’t try to do massive changes all at once with a team that has not bought-into those changes.  Taking an incremental approach has a greater chance of success. I see something similar in my day job all the time too.  Clients who for one reason or another claim to not be fans of agile (or not ready for agile yet).  But then they go on to ask me to help them get shorter feedback cycles, quicker delivery cycles, iterative development processes, etc.  It’s kind of funny at times, sometimes you just need to phrase the suggestions in terms they are using and avoid the word “agile”. PS – I haven’t blogged all that much over the past couple of years, but in an attempt to motivate myself, a few of us have accepted a blogger challenge.  There’s 6 of us who have all put some money into a pool, and the agreement is that we each need to blog at least once every 2-weeks.  The first 2-week period that we miss we’re eliminated.  Last person standing gets the money.  So expect at least one blog post every couple of weeks for the near future (I hope!).  And check out the blogs of the other 5 people in this blogger challenge: Steve Rogalsky: http://winnipegagilist.blogspot.ca Aaron Kowall: http://www.geekswithblogs.net/caffeinatedgeek Tyler Doerkson: http://blog.tylerdoerksen.com David Alpert: http://www.spinthemoose.com Dave White: http://www.agileramblings.com (note: site not available yet.  should be shortly or he owes me some money!)

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  • Documenting your database with Visual Studio 2012 SSDT tools

    - by krislankford
    The title of this post is interesting and something I am wishing you and your colleagues had a better way to do. I understand as I am asked this question frequently. I couple of weeks ago I was asked the same question by a customer who documents their database using the ApexSQL Doc tools which uses the extended properties on objects to create automated documentation. I thought that was super interesting and went down the path to see how we could could support the creation of this documentation while leveraging the Visual Studio 2012 SSDT Tools. What I found is was rather intriguing. There is a property called “Description” on all objects in the SSDT tools. This property is rather subtle and I am betting overlooked. To be honest, this property has probably been there for a while and I just never discovered it. Adding text to this '”Description” property it allows Visual Studio to create the commands for the extended properties directly to your schema which should be version controlled. As I did more digging there seemed to be extended properties at every level in the SQL database objects. This fills some rather challenging gaps and allows organizations to manage SQL Schema using the Visual Studio SQL database tools while allowing a way to automatically document the database. This will also work in the automation of the creation and alter scripts that can be generated as part f an automated build system. Now we essentially get a way to store, build and document the database in a nice little ALM package. Happy Coding!

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  • C++ Numerical Recipes &ndash; A New Adventure!

    - by JoshReuben
    I am about to embark on a great journey – over the next 6 weeks I plan to read through C++ Numerical Recipes 3rd edition http://amzn.to/YtdpkS I'll be reading this with an eye to C++ AMP, thinking about implementing the suitable subset (non-recursive, additive, commutative) to run on the GPU. APIs supporting HPC, GPGPU or MapReduce are all useful – providing you have the ability to choose the correct algorithm to leverage on them. I really think this is the most fascinating area of programming – a lot more exciting than LOB CRUD !!! When you think about it , everything is a function – we categorize & we extrapolate. As abstractions get higher & less leaky, sooner or later information systems programming will become a non-programmer task – you will be using WYSIWYG designers to build: GUIs MVVM service mapping & virtualization workflows ORM Entity relations In the data source SharePoint / LightSwitch are not there yet, but every iteration gets closer. For information workers, managed code is a race to the bottom. As MS futures are a bit shaky right now, the provider agnostic nature & higher barriers of entry of both C++ & Numerical Analysis seem like a rational choice to me. Its also fascinating – stepping outside the box. This is not the first time I've delved into numerical analysis. 6 months ago I read Numerical methods with Applications, which can be found for free online: http://nm.mathforcollege.com/ 2 years ago I learned the .NET Extreme Optimization library www.extremeoptimization.com – not bad 2.5 years ago I read Schaums Numerical Analysis book http://amzn.to/V5yuLI - not an easy read, as topics jump back & forth across chapters: 3 years ago I read Practical Numerical Methods with C# http://amzn.to/V5yCL9 (which is a toy learning language for this kind of stuff) I also read through AI a Modern Approach 3rd edition END to END http://amzn.to/V5yQSp - this took me a few years but was the most rewarding experience. I'll post progress updates – see you on the other side !

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  • Windows for IoT, continued

    - by Valter Minute
    Originally posted on: http://geekswithblogs.net/WindowsEmbeddedCookbook/archive/2014/08/05/windows-for-iot-continued.aspxI received many interesting feedbacks on my previous blog post and I tried to find some time to do some additional tests. Bert Kleinschmidt pointed out that pins 2,3 and 10 of the Galileo are connected directly to the SOC, while pin 13, the one used for the sample sketch is controlled via an I2C I/O expander. I changed my code to use pin 2 instead of 13 (just changing the variable assignment at the beginning of the code) and latency was greatly reduced. Now each pulse lasts for 1.44ms, 44% more than the expected time, but ways better that the result we got using pin 13. I also used SetThreadPriority to increase the priority of the thread that was running the sketch to THREAD_PRIORITY_HIGHEST but that didn't change the results. When I was using the I2C-controlled pin I tried the same and the timings got ways worse (increasing more than 10 times) and so I did not commented on that part, wanting to investigate the issua a bit more in detail. It seems that increasing the priority of the application thread impacts negatively the I2C communication. I tried to use also the Linux-based implementation (using a different Galileo board since the one provided by MS seems to use a different firmware) and the results of running the sample blink sketch modified to use pin 2 and blink the led for 1ms are similar to those we got on the same board running Windows. Here the difference between expected time and measured time is worse, getting around 3.2ms instead of 1 (320% compared to 150% using Windows but far from the 100.1% we got with the 8-bit Arduino). Both systems were not under load during the test, maybe loading some applications that use part of the CPU time would make those timings even less reliable, but I think that those numbers are enough to draw some conclusions. It may not be worth running a full OS if what you need is Arduino compatibility. The Arduino UNO is probably the best Arduino you can find to perform this kind of development. The Galileo running the Linux-based stack or running Windows for IoT is targeted to be a platform for "Internet of Things" devices, whatever that means. At the moment I don't see the "I" part of IoT. We have low level interfaces (SPI, I2C, the GPIO pins) that can be used to connect sensors but the support for connectivity is limited and the amount of work required to deliver some data to the cloud (using a secure HTTP request or a message queuing system like APMQS or MQTT) is still big and the rich OS underneath seems to not provide any help doing that.Why should I use sockets and can't access all the high level connectivity features we have on "full" Windows?I know that it's possible to use some third party libraries, try to build them using the Windows For IoT SDK etc. but this means re-inventing the wheel every time and can also lead to some IP concerns if used for products meant to be closed-source. I hope that MS and Intel (and others) will focus less on the "coolness" of running (some) Arduino sketches and more on providing a better platform to people that really want to design devices that leverage internet connectivity and the cloud processing power to deliver better products and services. Providing a reliable set of connectivity services would be a great start. Providing support for .NET would be even better, leaving native code available for hardware access etc. I know that those components may require additional storage and memory etc. So making the OS componentizable (or, at least, provide a way to install additional components) would be a great way to let developers pick the parts of the system they need to develop their solution, knowing that they will integrate well together. I can understand that the Arduino and Raspberry Pi* success may have attracted the attention of marketing departments worldwide and almost any new development board those days is promoted as "XXX response to Arduino" or "YYYY alternative to Raspberry Pi", but this is misleading and prevents companies from focusing on how to deliver good products and how to integrate "IoT" features with their existing offer to provide, at the end, a better product or service to their customers. Marketing is important, but can't decide the key features of a product (the OS) that is going to be used to develop full products for end customers integrating it with hardware and application software. I really like the "hackable" nature of open-source devices and like to see that companies are getting more and more open in releasing information, providing "hackable" devices and supporting developers with documentation, good samples etc. On the other side being able to run a sketch designed for an 8 bit microcontroller on a full-featured application processor may sound cool and an easy upgrade path for people that just experimented with sensors etc. on Arduino but it's not, in my humble opinion, the main path to follow for people who want to deliver real products.   *Shameless self-promotion: if you are looking for a good book in Italian about the Raspberry Pi , try mine: http://www.amazon.it/Raspberry-Pi-alluso-Digital-LifeStyle-ebook/dp/B00GYY3OKO

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  • Add SQL Azure database to Azure Web Role and persist data with entity framework code first.

    - by MagnusKarlsson
    In my last post I went for a warts n all approach to set up a web role on Azure. In this post I’ll describe how to add an SQL Azure database to the project. This will be described with an as minimal as possible amount of code and screen dumps. All questions are welcome in the comments area. Please don’t email since questions answered in the comments field is made available to other visitors. As an example we will add a comments section to the site we used in the previous post (Länk här). Steps: 1. Create a Comments entity and then use Scaffolding to set up controller and view, and add ConnectionString to web.config. 2. Create SQL Azure database in Management Portal and link the new database 3. Test it online!   1. Right click Models folder, choose add, choose “class…” . Name the Class Comment. 1.1 Replace the Code in the class with the following: using System.Data.Entity; namespace MvcWebRole1.Models { public class Comment {    public int CommentId { get; set; }    public string Name { get; set; }      public string Content { get; set; } } public class CommentsDb : DbContext { public DbSet<Comment> CommentEntries { get; set; } } } Now Entity Framework can create a database and a table named Comment. Build your project to assert there are no build errors.   1.2 Right click Controllers folder, choose add, choose “class…” . Name the Class CommentController and fill out the values as in the example below.     1.3 Click Add. Visual Studio now creates default View for CRUD operations and a Controller adhering to these and opens them. 1.3 Open Web.config and add the following connectionstring in <connectionStrings> node. <add name="CommentsDb” connectionString="data source=(LocalDB)\v11.0;Integrated Security=SSPI;AttachDbFileName=|DataDirectory|\CommentsDb.mdf;Initial Catalog=CommentsDb;MultipleActiveResultSets=True" providerName="System.Data.SqlClient" />   1.4 Save All and press F5 to start the application. 1.5 Go to http://127.0.0.1:81/Comments which will redirect you through CommentsController to the Index View which looks like this:     Click Create new. In the Create-view, add name and content and press Create.   1: // 2: // POST: /Comments/Create 3:  4: [HttpPost] 5: public ActionResult Create(Comment comment) 6: { 7: if (ModelState.IsValid) 8: { 9: db.CommentEntries.Add(comment); 10: db.SaveChanges(); 11: return RedirectToAction("Index"); 12: } 13:  14: return View(comment); 15: } 16:    The default View() is Index so that is the View you will come to. Looking like this: 1: // 2: // GET: /Comments/ 3: 4: public ActionResult Index() 5: { 6: return View(db.CommentEntries.ToList()); 7: } Resulting in the following screen dump(success!):   2. Now, go to the Management portal and Create a new db.   2.1 With the new database created. Click the DB icon in the left most menu. Then click the newly created database. Click DASHBOARD in the top menu. Finally click Connections strings in the right menu to get the connection string we need to add in our web.debug.config file.   2.2 Now, take a copy of the connection String earlier added to the web.config and paste in web.debug.conifg in the connectionstrings node. Replace everything within “ “ in the copied connectionstring with that you got from SQL Azure. You will have something like this:   2.3 Rebuild the application, right click the cloud project and choose “Package…” (if you haven’t set up publishing profile which we will do in our next blog post). Remember to choose the right config file, use debug for staging and release for production so your databases won’t collide. You should see something like this:   2.4 Go to Management Portal and click the Web Services menu, choose your service and click update in the bottom menu.   2.5 Link the newly created database to your application. Click the LINKED RESOURCES in the top menu and then click “Link” in the bottom menu. You should get something like this. 3. Alright then. Under the Dashboard you can find the link to your application. Click it to open it in a browser and then go to ~/Comments to try it out just the way we did locally. Success and end of this story!

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  • Computer Networks UNISA - Chap 10 &ndash; In Depth TCP/IP Networking

    - by MarkPearl
    After reading this section you should be able to Understand methods of network design unique to TCP/IP networks, including subnetting, CIDR, and address translation Explain the differences between public and private TCP/IP networks Describe protocols used between mail clients and mail servers, including SMTP, POP3, and IMAP4 Employ multiple TCP/IP utilities for network discovery and troubleshooting Designing TCP/IP-Based Networks The following sections explain how network and host information in an IPv4 address can be manipulated to subdivide networks into smaller segments. Subnetting Subnetting separates a network into multiple logically defined segments, or subnets. Networks are commonly subnetted according to geographic locations, departmental boundaries, or technology types. A network administrator might separate traffic to accomplish the following… Enhance security Improve performance Simplify troubleshooting The challenges of Classful Addressing in IPv4 (No subnetting) The simplest type of IPv4 is known as classful addressing (which was the Class A, Class B & Class C network addresses). Classful addressing has the following limitations. Restriction in the number of usable IPv4 addresses (class C would be limited to 254 addresses) Difficult to separate traffic from various parts of a network Because of the above reasons, subnetting was introduced. IPv4 Subnet Masks Subnetting depends on the use of subnet masks to identify how a network is subdivided. A subnet mask indicates where network information is located in an IPv4 address. The 1 in a subnet mask indicates that corresponding bits in the IPv4 address contain network information (likewise 0 indicates the opposite) Each network class is associated with a default subnet mask… Class A = 255.0.0.0 Class B = 255.255.0.0 Class C = 255.255.255.0 An example of calculating  the network ID for a particular device with a subnet mask is shown below.. IP Address = 199.34.89.127 Subnet Mask = 255.255.255.0 Resultant Network ID = 199.34.89.0 IPv4 Subnetting Techniques Subnetting breaks the rules of classful IPv4 addressing. Read page 490 for a detailed explanation Calculating IPv4 Subnets Read page 491 – 494 for an explanation Important… Subnetting only applies to the devices internal to your network. Everything external looks at the class of the IP address instead of the subnet network ID. This way, traffic directed to your network externally still knows where to go, and once it has entered your internal network it can then be prioritized and segmented. CIDR (classless Interdomain Routing) CIDR is also known as classless routing or supernetting. In CIDR conventional network class distinctions do not exist, a subnet boundary can move to the left, therefore generating more usable IP addresses on your network. A subnet created by moving the subnet boundary to the left is known as a supernet. With CIDR also came new shorthand for denoting the position of subnet boundaries known as CIDR notation or slash notation. CIDR notation takes the form of the network ID followed by a forward slash (/) followed by the number of bits that are used for the extended network prefix. To take advantage of classless routing, your networks routers must be able to interpret IP addresses that don;t adhere to conventional network class parameters. Routers that rely on older routing protocols (i.e. RIP) are not capable of interpreting classless IP addresses. Internet Gateways Gateways are a combination of software and hardware that enable two different network segments to exchange data. A gateway facilitates communication between different networks or subnets. Because on device cannot send data directly to a device on another subnet, a gateway must intercede and hand off the information. Every device on a TCP/IP based network has a default gateway (a gateway that first interprets its outbound requests to other subnets, and then interprets its inbound requests from other subnets). The internet contains a vast number of routers and gateways. If each gateway had to track addressing information for every other gateway on the Internet, it would be overtaxed. Instead, each handles only a relatively small amount of addressing information, which it uses to forward data to another gateway that knows more about the data’s destination. The gateways that make up the internet backbone are called core gateways. Address Translation An organizations default gateway can also be used to “hide” the organizations internal IP addresses and keep them from being recognized on a public network. A public network is one that any user may access with little or no restrictions. On private networks, hiding IP addresses allows network managers more flexibility in assigning addresses. Clients behind a gateway may use any IP addressing scheme, regardless of whether it is recognized as legitimate by the Internet authorities but as soon as those devices need to go on the internet, they must have legitimate IP addresses to exchange data. When a clients transmission reaches the default gateway, the gateway opens the IP datagram and replaces the client’s private IP address with an Internet recognized IP address. This process is known as NAT (Network Address Translation). TCP/IP Mail Services All Internet mail services rely on the same principles of mail delivery, storage, and pickup, though they may use different types of software to accomplish these functions. Email servers and clients communicate through special TCP/IP application layer protocols. These protocols, all of which operate on a variety of operating systems are discussed below… SMTP (Simple Mail transfer Protocol) The protocol responsible for moving messages from one mail server to another over TCP/IP based networks. SMTP belongs to the application layer of the ODI model and relies on TCP as its transport protocol. Operates from port 25 on the SMTP server Simple sub-protocol, incapable of doing anything more than transporting mail or holding it in a queue MIME (Multipurpose Internet Mail Extensions) The standard message format specified by SMTP allows for lines that contain no more than 1000 ascii characters meaning if you relied solely on SMTP you would have very short messages and nothing like pictures included in an email. MIME us a standard for encoding and interpreting binary files, images, video, and non-ascii character sets within an email message. MIME identifies each element of a mail message according to content type. MIME does not replace SMTP but works in conjunction with it. Most modern email clients and servers support MIME POP (Post Office Protocol) POP is an application layer protocol used to retrieve messages from a mail server POP3 relies on TCP and operates over port 110 With POP3 mail is delivered and stored on a mail server until it is downloaded by a user Disadvantage of POP3 is that it typically does not allow users to save their messages on the server because of this IMAP is sometimes used IMAP (Internet Message Access Protocol) IMAP is a retrieval protocol that was developed as a more sophisticated alternative to POP3 The single biggest advantage IMAP4 has over POP3 is that users can store messages on the mail server, rather than having to continually download them Users can retrieve all or only a portion of any mail message Users can review their messages and delete them while the messages remain on the server Users can create sophisticated methods of organizing messages on the server Users can share a mailbox in a central location Disadvantages of IMAP are typically related to the fact that it requires more storage space on the server. Additional TCP/IP Utilities Nearly all TCP/IP utilities can be accessed from the command prompt on any type of server or client running TCP/IP. The syntaxt may differ depending on the OS of the client. Below is a list of additional TCP/IP utilities – research their use on your own! Ipconfig (Windows) & Ifconfig (Linux) Netstat Nbtstat Hostname, Host & Nslookup Dig (Linux) Whois (Linux) Traceroute (Tracert) Mtr (my traceroute) Route

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