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  • SOA &amp; Application Grid Specialization &ndash; 6 steps to success &ndash; part 1 OMM

    - by Jürgen Kress
    SOA Specialization – Oracle Open Market Model (OMM) Dear Application Grid SOA Partners, Or goal is to SOA Specialize you, in the next weeks we will inform you in a series how you can achieve SOA Specialization. Specialization is key the be recognized by Oracle and to be preferred by our Customers. The first step to become SOA Specialized is to proof 2 transactions. You can either resell, co-sell or referral – as a proof point we do use our Open Market Model (OMM). To create your account go to our new Partner Portal: go to login of your OPN-Homepage: http://oraclepartnernetwork.oracle.com click on: "Sales" "Create a PRM User Account" Enter your User ID: Enter Company Identifier: ((please ask your OPN IC)) Finish Wait for a Confirmation Email If you need OMM support please contact out dedicated team: Nordics  please ask: [email protected] Portugal, Spain please ask: [email protected] Austria, Belgium, Germany, Luxembourg, Netherlands, Switzerland, United Arab Emirates, United Kingdom please ask: [email protected] For more information about OMM watch our on-demand webcast “Recognising the Value of Partners: Register Oracle Deals through the Open Market Model (OMM)”. Become SOA Specialized today SOA Specialized & Application Grid Specialized Create your references, create your OMM Entry, take the SOA Sales assessment, take the SOA Pre-Sales assessment, take the Support assessment and register for the SOA Implementation assessment. For more information on Specialization please visit our OPN Specialized Webcast Series To get support on Specialization please contact the Partner Business Centers.   SOA Specialized Application Grid Specialized Proof 2 transactions with OMM Proof 2 transactions with OMM Create your 2 references Create your 2 references SOA Sales assessment 3, Oracle Application Grid Sales Specialist  SOA Pre-Sales assessment 3 Oracle Application Grid PreSales Specialist Support assessment 1 Support assessment 2 SOA Implementation assessment 4 Application Grid Implementation assessment 4

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  • Can Search Engine Optimization Actually Help Your Online Business

    Search engine optimization or SEO is a concept that has come about in the internet world and it sure enough is a concept that is guaranteed to save a dying website in no time. If you have heard quite a bit about search engine optimization and how best it can save your business from going down the drain but do not know how can utilize the service to save your online business, then you have come to the right place because, here, you are going to find out about some very important information that will help you understand this particular concept better.

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  • DatagGridViewColumn.DataPropertyName to an array element?

    - by unknown
    Hi there, I'm using a DataGridView binding its datasource to a List, and specifying the properties for each column. An example would be: DataGridViewTextBoxColumn colConcept = new DataGridViewTextBoxColumn(); DataGridViewCell cell4 = new DataGridViewTextBoxCell(); colConcept.CellTemplate = cell4; colConcept.Name = "concept"; colConcept.HeaderText = "Concept"; colConcept.DataPropertyName = "Concept"; colConcept.Width = 200; this.dataGridViewBills.Columns.Add(colConcept); {... assign other colums...} And finally this.dataGridViewBills.DataSource=billslist; //billslist is List<Bill> Obviously Class Bill has a Property called Concept, as well as one Property for each column. Well, now my problem, is that Bill should have and Array/List/whateverdynamicsizecontainer of strings called Years. Let's assume that every Bill will have the same Years.Count, but this only known at runtime.Thus, I can't specify properties like Bill.FirstYear to obtain Bill.Years[0], Bill.SecondYear to obtain Bills.Years[1]... etc... and bind it to each column. The idea, is that now I want to have a grid with dynamic number of colums (known at runtime), and each column filled with a string from the Bill.Years List. I can make a loop to add columns to the grid at runtime depending of Bill.Years.Count, but is possible to bind them to each of the strings that the Bill.Years List contains??? I'm not sure if I'm clear enough. The result ideally would be something like this, for 2 bills on the list, and 3 years for each bill: --------------------------------------GRID HEADER------------------------------- NAME CONCEPT YEAR1 YEAR2 YEAR3 --------------------------------------GRID VALUES------------------------------- Bill1 Bill1.Concept Bill1.Years[0] Bill1.Years[1] Bill1.Years[2] Bill2 Bill2.Concept Bill2.Years[0] Bill2.Years[1] Bill2.Years[2] I can always forget the datasource, and write each cell manually, as the MSFlexGrid used to like, but if possible, I would like to use the binding capabilities of the DataGridView. Any ideas? Thanks a lot.

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  • Improving abysmal 802.11n wireless network

    - by concept
    I am in desperate need of help to improve the abysmal performance of my 802.11n wireless network. At best I get 30Mbs (this is an internet download) from a technology that boasts 300Mbs, even worse is the LAN where to date best i have ever gotten is 1Mbs. It is literally quicker to copy the file to a USB and walk it to the other computer. Infrastructure is this AP 802.11n only broadcasting at both 2.4GHz and 5GHz Mac with 802.11a/b/g/n card is connected to the AP via 5GHz Linux with 802.11a/b/g/n card is connected to AP via 2.4GHz I have conducted the following tests (results at end of post) Internet based speed test wired and wireless LAN file copy wired and wireless I have read: http://nutsaboutnets.com/troubleshooting-wi-fi-problems/ http://www.smallnetbuilder.com/wireless/wireless-basics/30664-5-ways-to-fix-slow-80211n-- speed http colon //www.wi-fiplanet dot com/tutorials/7-tips-to-increase-wi-fi-performance.html Slow file transfer on network between two 802.11n laptops (connected directly together via access point) Wireless Network Performance Issues Slower than expected 802.11n wireless network speeds I have made the following optimizations AP broadcasts only 802.11n on both 2.4GHz and 5GHz frequencies 2.4GHz is on a channel with least interference (live in an apartment with lots of APs), this did make a 10Mb/sec improvement Our AP is the only one transmitting on the 5GHz freq. Security: WPA Personal WPA2 AES encryption Bandwidth: 20MHz / 40MHz (i assume this to be channel bonding) I have tried the following with 0 improvement Dropped the Fragment Threshold to 512 Dropped the Request To Send (RTS) Threshold to 512 and 1 Even thought of buying a frequency spectrum analyzer, until i saw the cost of them!!! Speed test results Linux Wired: DOWNLOAD 128.40Mb/s UPLOAD 10.62Mb/s www dot speedtest dot net/my-result/2948381853 Mac Wired: DOWNLOAD 118.02Mb/s UPLOAD 10.56Mb/s www dot speedtest dot net/my-result/2948384406 Linux Wireless: DOWNLOAD 23.99Mb/s UPLOAD 10.31Mb/s www.speedtest dot net/my-result/2948394990 Mac Wireless: DOWNLOAD 22.55Mb/s UPLOAD 10.36Mb/s www.speedtest dot net/my-result/2948396489 LAN NFS 53,345,087 bytes (51Mb) file Linux Mac NFS Wired: 65.6959 Mb/sec Linux Mac NFS Wireless: .9443 Mb/sec All help is appreciated, even testing methods will be accepted.

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  • Django: select_related and GenericRelation

    - by Parand
    Does select_related work for GenericRelation relations, or is there a reasonable alternative? At the moment Django's doing individual sql calls for each item in my queryset, and I'd like to avoid that using something like select_related. class Claim(models.Model): proof = generic.GenericRelation(Proof) class Proof(models.Model): content_type = models.ForeignKey(ContentType) object_id = models.PositiveIntegerField() content_object = generic.GenericForeignKey('content_type', 'object_id') I'm selecting a bunch of Claims, and I'd like the related Proofs to be pulled in instead of queried individually.

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  • Abstraction, Politics, and Software Architecture

    Abstraction can be defined as a general concept and/or idea that lack any concrete details. Throughout history this type of thinking has led to an array of new ideas and innovations as well as increased confusion and conspiracy. If one was to look back at our history they will see that abstraction has been used in various forms throughout our past. When I was growing up I do not know how many times I heard politicians say “Leave no child left behind” or “No child left behind” as a major part of their campaign rhetoric in regards to a stance on education. As you can see their slogan is a perfect example of abstraction because it only offers a very general concept about improving our education system but they do not mention how they would like to do it. If they did then they would be adding concrete details to their abstraction thus turning it in to an actual working plan as to how we as a society can help children succeed in school and in life, but then they would not be using abstraction. By now I sure you are thinking what does abstraction have to do with software architecture. You are valid in thinking this way, but abstraction is a wonderful tool used in information technology especially in the world of software architecture. Abstraction is one method of extracting the concepts of an idea so that it can be understood and discussed by others of varying technical abilities and backgrounds. One ways in which I tend to extract my architectural design thoughts is through the use of basic diagrams to convey an idea for a system or a new feature for an existing application. This allows me to generically model an architectural design through the use of views and Unified Markup Language (UML). UML is a standard method for creating a 4+1 Architectural View Models. The 4+1 Architectural View Model consists of 4 views typically created with UML as well as a general description of the concept that is being expressed by a model. The 4+1 Architectural View Model: Logical View: Models a system’s end-user functionality. Development View: Models a system as a collection of components and connectors to illustrate how it is intended to be developed.  Process View: Models the interaction between system components and connectors as to indicate the activities of a system. Physical View: Models the placement of the collection of components and connectors of a system within a physical environment. Recently I had to use the concept of abstraction to express an idea for implementing a new security framework on an existing website. My concept would add session based management in order to properly secure and allow page access based on valid user credentials and last user activity.  I created a basic Process View by using UML diagrams to communicate the basic process flow of my changes in the application so that all of the projects stakeholders would be able to understand my idea. Additionally I created a Logical View on a whiteboard while conveying the process workflow with a few stakeholders to show how end-user will be affected by the new framework and gaining additional input about the design. After my Logical and Process Views were accepted I then started on creating a more detailed Development View in order to map how the system will be built based on the concept of components and connections based on the previously defined interactions. I really did not need to create a Physical view for this idea because we were updating an existing system that was already deployed based on an existing Physical View. What do you think about the use of abstraction in the development of software architecture? Please let me know.

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  • SOA Governance Starts with People and Processes

    - by Jyothi Swaroop
    While we all agree that SOA Governance is about People, Processes and Technology. Some experts are of the opinion that SOA Governance begins with People and Processes but needs to be empowered with technology to achieve the best results. Here's an interesting piece from David Linthicum on eBizq: In the world of SOA, the concept of SOA governance is getting a lot of attention. However, how SOA governance is defined and implemented really depends on the SOA governance vendor who just left the building within most enterprises. Indeed, confusion is a huge issue when considering SOA governance, and the core issues are more about the fundamentals of people and processes, and not about the technology. SOA governance is a concept used for activities related to exercising control over services in an SOA, including tracking the services, monitoring the service, and controlling changes made to the services, simple put. The trouble comes in when SOA governance vendors attempt to define SOA governance around their technology, all with different approaches to SOA governance. Thus, it's important that those building SOAs within the enterprise take a step back and understand what really need to support the concept of SOA governance. The value of SOA governance is pretty simple. Since services make up the foundation of an SOA, and are at their essence the behavior and information from existing systems externalized, it's critical to make sure that those accessing, creating, and changing services do so using a well controlled and orderly mechanism. Those of you, who already have governance in place, typically around enterprise architecture efforts, will be happy to know that SOA governance does not replace those processes, but becomes a mechanism within the larger enterprise governance concept. People and processes are first thing on the list to get under control before you begin to toss technology at this problem. This means establishing an understanding of SOA governance within the team members, including why it's important, who's involved, and the core processes that are to be follow to make SOA governance work. Indeed, when creating the core SOA governance strategy should really be independent of the technology. The technology will change over the years, but the core processes and discipline should be relatively durable over time.

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  • Solving Big Problems with Oracle R Enterprise, Part II

    - by dbayard
    Part II – Solving Big Problems with Oracle R Enterprise In the first post in this series (see https://blogs.oracle.com/R/entry/solving_big_problems_with_oracle), we showed how you can use R to perform historical rate of return calculations against investment data sourced from a spreadsheet.  We demonstrated the calculations against sample data for a small set of accounts.  While this worked fine, in the real-world the problem is much bigger because the amount of data is much bigger.  So much bigger that our approach in the previous post won’t scale to meet the real-world needs. From our previous post, here are the challenges we need to conquer: The actual data that needs to be used lives in a database, not in a spreadsheet The actual data is much, much bigger- too big to fit into the normal R memory space and too big to want to move across the network The overall process needs to run fast- much faster than a single processor The actual data needs to be kept secured- another reason to not want to move it from the database and across the network And the process of calculating the IRR needs to be integrated together with other database ETL activities, so that IRR’s can be calculated as part of the data warehouse refresh processes In this post, we will show how we moved from sample data environment to working with full-scale data.  This post is based on actual work we did for a financial services customer during a recent proof-of-concept. Getting started with the Database At this point, we have some sample data and our IRR function.  We were at a similar point in our customer proof-of-concept exercise- we had sample data but we did not have the full customer data yet.  So our database was empty.  But, this was easily rectified by leveraging the transparency features of Oracle R Enterprise (see https://blogs.oracle.com/R/entry/analyzing_big_data_using_the).  The following code shows how we took our sample data SimpleMWRRData and easily turned it into a new Oracle database table called IRR_DATA via ore.create().  The code also shows how we can access the database table IRR_DATA as if it was a normal R data.frame named IRR_DATA. If we go to sql*plus, we can also check out our new IRR_DATA table: At this point, we now have our sample data loaded in the database as a normal Oracle table called IRR_DATA.  So, we now proceeded to test our R function working with database data. As our first test, we retrieved the data from a single account from the IRR_DATA table, pull it into local R memory, then call our IRR function.  This worked.  No SQL coding required! Going from Crawling to Walking Now that we have shown using our R code with database-resident data for a single account, we wanted to experiment with doing this for multiple accounts.  In other words, we wanted to implement the split-apply-combine technique we discussed in our first post in this series.  Fortunately, Oracle R Enterprise provides a very scalable way to do this with a function called ore.groupApply().  You can read more about ore.groupApply() here: https://blogs.oracle.com/R/entry/analyzing_big_data_using_the1 Here is an example of how we ask ORE to take our IRR_DATA table in the database, split it by the ACCOUNT column, apply a function that calls our SimpleMWRR() calculation, and then combine the results. (If you are following along at home, be sure to have installed our myIRR package on your database server via  “R CMD INSTALL myIRR”). The interesting thing about ore.groupApply is that the calculation is not actually performed in my desktop R environment from which I am running.  What actually happens is that ore.groupApply uses the Oracle database to perform the work.  And the Oracle database is what actually splits the IRR_DATA table by ACCOUNT.  Then the Oracle database takes the data for each account and sends it to an embedded R engine running on the database server to apply our R function.  Then the Oracle database combines all the individual results from the calls to the R function. This is significant because now the embedded R engine only needs to deal with the data for a single account at a time.  Regardless of whether we have 20 accounts or 1 million accounts or more, the R engine that performs the calculation does not care.  Given that normal R has a finite amount of memory to hold data, the ore.groupApply approach overcomes the R memory scalability problem since we only need to fit the data from a single account in R memory (not all of the data for all of the accounts). Additionally, the IRR_DATA does not need to be sent from the database to my desktop R program.  Even though I am invoking ore.groupApply from my desktop R program, because the actual SimpleMWRR calculation is run by the embedded R engine on the database server, the IRR_DATA does not need to leave the database server- this is both a performance benefit because network transmission of large amounts of data take time and a security benefit because it is harder to protect private data once you start shipping around your intranet. Another benefit, which we will discuss in a few paragraphs, is the ability to leverage Oracle database parallelism to run these calculations for dozens of accounts at once. From Walking to Running ore.groupApply is rather nice, but it still has the drawback that I run this from a desktop R instance.  This is not ideal for integrating into typical operational processes like nightly data warehouse refreshes or monthly statement generation.  But, this is not an issue for ORE.  Oracle R Enterprise lets us run this from the database using regular SQL, which is easily integrated into standard operations.  That is extremely exciting and the way we actually did these calculations in the customer proof. As part of Oracle R Enterprise, it provides a SQL equivalent to ore.groupApply which it refers to as “rqGroupEval”.  To use rqGroupEval via SQL, there is a bit of simple setup needed.  Basically, the Oracle Database needs to know the structure of the input table and the grouping column, which we are able to define using the database’s pipeline table function mechanisms. Here is the setup script: At this point, our initial setup of rqGroupEval is done for the IRR_DATA table.  The next step is to define our R function to the database.  We do that via a call to ORE’s rqScriptCreate. Now we can test it.  The SQL you use to run rqGroupEval uses the Oracle database pipeline table function syntax.  The first argument to irr_dataGroupEval is a cursor defining our input.  You can add additional where clauses and subqueries to this cursor as appropriate.  The second argument is any additional inputs to the R function.  The third argument is the text of a dummy select statement.  The dummy select statement is used by the database to identify the columns and datatypes to expect the R function to return.  The fourth argument is the column of the input table to split/group by.  The final argument is the name of the R function as you defined it when you called rqScriptCreate(). The Real-World Results In our real customer proof-of-concept, we had more sophisticated calculation requirements than shown in this simplified blog example.  For instance, we had to perform the rate of return calculations for 5 separate time periods, so the R code was enhanced to do so.  In addition, some accounts needed a time-weighted rate of return to be calculated, so we extended our approach and added an R function to do that.  And finally, there were also a few more real-world data irregularities that we needed to account for, so we added logic to our R functions to deal with those exceptions.  For the full-scale customer test, we loaded the customer data onto a Half-Rack Exadata X2-2 Database Machine.  As our half-rack had 48 physical cores (and 96 threads if you consider hyperthreading), we wanted to take advantage of that CPU horsepower to speed up our calculations.  To do so with ORE, it is as simple as leveraging the Oracle Database Parallel Query features.  Let’s look at the SQL used in the customer proof: Notice that we use a parallel hint on the cursor that is the input to our rqGroupEval function.  That is all we need to do to enable Oracle to use parallel R engines. Here are a few screenshots of what this SQL looked like in the Real-Time SQL Monitor when we ran this during the proof of concept (hint: you might need to right-click on these images to be able to view the images full-screen to see the entire image): From the above, you can notice a few things (numbers 1 thru 5 below correspond with highlighted numbers on the images above.  You may need to right click on the above images and view the images full-screen to see the entire image): The SQL completed in 110 seconds (1.8minutes) We calculated rate of returns for 5 time periods for each of 911k accounts (the number of actual rows returned by the IRRSTAGEGROUPEVAL operation) We accessed 103m rows of detailed cash flow/market value data (the number of actual rows returned by the IRR_STAGE2 operation) We ran with 72 degrees of parallelism spread across 4 database servers Most of our 110seconds was spent in the “External Procedure call” event On average, we performed 8,200 executions of our R function per second (110s/911k accounts) On average, each execution was passed 110 rows of data (103m detail rows/911k accounts) On average, we did 41,000 single time period rate of return calculations per second (each of the 8,200 executions of our R function did rate of return calculations for 5 time periods) On average, we processed over 900,000 rows of database data in R per second (103m detail rows/110s) R + Oracle R Enterprise: Best of R + Best of Oracle Database This blog post series started by describing a real customer problem: how to perform a lot of calculations on a lot of data in a short period of time.  While standard R proved to be a very good fit for writing the necessary calculations, the challenge of working with a lot of data in a short period of time remained. This blog post series showed how Oracle R Enterprise enables R to be used in conjunction with the Oracle Database to overcome the data volume and performance issues (as well as simplifying the operations and security issues).  It also showed that we could calculate 5 time periods of rate of returns for almost a million individual accounts in less than 2 minutes. In a future post, we will take the same R function and show how Oracle R Connector for Hadoop can be used in the Hadoop world.  In that next post, instead of having our data in an Oracle database, our data will live in Hadoop and we will how to use the Oracle R Connector for Hadoop and other Oracle Big Data Connectors to move data between Hadoop, R, and the Oracle Database easily.

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  • What are some concepts people should understand before programming "big" projects?

    - by Abafei
    A person new to programming may be able to make a good small program. However, when starting to work on anything bigger than a small (think 1 C source file or Python module) program, there are some general concepts which become much more important when working on "big" (think many Python modules or C files) programs; one example is modularity, another is having a set aim. Some of these may be obvious to people who went to school to learn programming; however, people like me who did not go to programming classes sometimes have to learn these things from experience, possibly creating failed projects in the meantime. ================================================== Please explain what the concept is, and why the concept becomes more important for big programs than by small programs. Please give only 1 concept per answer.

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  • The Emergence of a New Architecture for Long-term Data Retention

    - by Claudia Caramelli-Oracle
    Dear Partner, A new research report from Wikibon explains how the combination of flash and tape makes for a superior solution for long-term data archives versus using dedupe appliances. The combination of these two technologies, that have been in the market, one for a few years and the other for decades, introduces a new concept. The concept is “Flape”, a concept first coined by Wikibon in October of 2012. Flape is a combination of Flash (SSD) technology and tape…this combination of technologies when used for long-term archiving can save IT departments as much as 300% of their overall IT budget over the course of 10 years. Do you want to know more? You can review the whole report here.

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  • Is ROA a specific form of doing SOA?

    - by JohnDoDo
    I have read somewhere that ROA (Resource Oriented Architecture) is SOA (Service Oriented Architecture) with specific constraints added. SOA is the abstract concept of combining discrete pieces of software and ROA is an implementation of SOA with all of the constraints of RESTful services applied to it: SOA = the concept ROA = the concept + specific implementation details I also had my share of posts saying that ROA is different than SOA, then simply fallback to statements like "ROA is REST" and "SOA is SOAP" and presenting the same more or less pertinent comparisons and differences between SOAP and REST. So just to clear up my confusion: Is ROA a specific form of doing SOA?

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  • Opinion on "loop invariants", and are these frequently used in the industry?

    - by Michael Aaron Safyan
    I was thinking back to my freshman year at college (five years ago) when I took an exam to place-out of intro-level computer science. There was a question about loop invariants, and I was wondering if loop invariants are really necessary in this case or if the question was simply a bad example... the question was to write an iterative definition for a factorial function, and then to prove that the function was correct. The code that I provided for the factorial function was as follows: public static int factorial(int x) { if ( x < 0 ){ throw new IllegalArgumentException("Parameter must be = 0"); }else if ( x == 0 ){ return 1; }else{ int result = 1; for ( int i = 1; i <= x; i++ ){ result*=i; } return result; } } My own proof of correctness was a proof by cases, and in each I asserted that it was correct by definition (x! is undefined for negative values, 0! is 1, and x! is 1*2*3...*x for a positive value of x). The professor wanted me to prove the loop using a loop invariant; however, my argument was that it was correct "by definition", because the definition of "x!" for a positive integer x is "the product of the integers from 1... x", and the for-loop in the else clause is simply a literal translation of this definition. Is a loop invariant really needed as a proof of correctness in this case? How complicated must a loop be before a loop invariant (and proper initialization and termination conditions) become necessary for a proof of correctness? Additionally, I was wondering... how often are such formal proofs used in the industry? I have found that about half of my courses are very theoretical and proof-heavy and about half are very implementation and coding-heavy, without any formal or theoretical material. How much do these overlap in practice? If you do use proofs in the industry, when do you apply them (always, only if it's complicated, rarely, never)?

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  • RegEx for MetaMap in Java

    - by Christian
    MetaMap files have following lines: mappings([map(-1000,[ev(-1000,'C0018017','Objective','Goals',[objective],[inpr],[[[1,1],[1,1],0]],yes,no)])]). The format is explained as mappings( [map(negated overall score for this mapping, [ev(negated candidate score,'UMLS concept ID','UMLS concept','preferred name for concept - may or may not be different', [matched word or words lowercased that this candidate matches in the phrase - comma separated list], [semantic type(s) - comma separated list], [match map list - see below],candidate involved with head of phrase - yes or no, is this an overmatch - yes or no ) ] ) ] ). I want to run a RegEx query in java that gives me the Strings 'UMLS concept ID', semantic type and match map list. Is RegEx the right tool or what is the most efficent way to accomplish this in Java?

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  • Normalization in plain English

    - by Yada
    I sort of understand the concept of database normalization but always have a hard time explaining it in plain English especially for a job interview. I have read the wikipedia post, but still find it hard to explain the concept to none developers. "Design a database in a way not to get duplicated data" is the first thing that comes to mind. Does anyone was a nice way to explain the concept of database normalization in plain English. And what are some nice examples to show the differences between first, second and third normal forms. Say you go to a job interview and the person asks: Explain the concept of normalization and how would go about designing a normalized database. What key points are the interviewer looking for?

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  • Did Java invent interfaces?

    - by Jordão
    I know about C++ pure virtual classes, but Java went one step further and created a first-class (no pun intended) concept for multiple-interface (not implementation) inheritance, the interface. It's now a staple of major statically-typed languages. Did Java invent the interface concept? Or did it appear in older languages also as a first-class concept?

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  • Security in Software

    The term security has many meanings based on the context and perspective in which it is used. Security from the perspective of software/system development is the continuous process of maintaining confidentiality, integrity, and availability of a system, sub-system, and system data. This definition at a very high level can be restated as the following: Computer security is a continuous process dealing with confidentiality, integrity, and availability on multiple layers of a system. Key Aspects of Software Security Integrity Confidentiality Availability Integrity within a system is the concept of ensuring only authorized users can only manipulate information through authorized methods and procedures. An example of this can be seen in a simple lead management application.  If the business decided to allow each sales member to only update their own leads in the system and sales managers can update all leads in the system then an integrity violation would occur if a sales member attempted to update someone else’s leads. An integrity violation occurs when a team member attempts to update someone else’s lead because it was not entered by the sales member.  This violates the business rule that leads can only be update by the originating sales member. Confidentiality within a system is the concept of preventing unauthorized access to specific information or tools.  In a perfect world the knowledge of the existence of confidential information/tools would be unknown to all those who do not have access. When this this concept is applied within the context of an application only the authorized information/tools will be available. If we look at the sales lead management system again, leads can only be updated by originating sales members. If we look at this rule then we can say that all sales leads are confidential between the system and the sales person who entered the lead in to the system. The other sales team members would not need to know about the leads let alone need to access it. Availability within a system is the concept of authorized users being able to access the system. A real world example can be seen again from the lead management system. If that system was hosted on a web server then IP restriction can be put in place to limit access to the system based on the requesting IP address. If in this example all of the sales members where accessing the system from the 192.168.1.23 IP address then removing access from all other IPs would be need to ensure that improper access to the system is prevented while approved users can access the system from an authorized location. In essence if the requesting user is not coming from an authorized IP address then the system will appear unavailable to them. This is one way of controlling where a system is accessed. Through the years several design principles have been identified as being beneficial when integrating security aspects into a system. These principles in various combinations allow for a system to achieve the previously defined aspects of security based on generic architectural models. Security Design Principles Least Privilege Fail-Safe Defaults Economy of Mechanism Complete Mediation Open Design Separation Privilege Least Common Mechanism Psychological Acceptability Defense in Depth Least Privilege Design PrincipleThe Least Privilege design principle requires a minimalistic approach to granting user access rights to specific information and tools. Additionally, access rights should be time based as to limit resources access bound to the time needed to complete necessary tasks. The implications of granting access beyond this scope will allow for unnecessary access and the potential for data to be updated out of the approved context. The assigning of access rights will limit system damaging attacks from users whether they are intentional or not. This principle attempts to limit data changes and prevents potential damage from occurring by accident or error by reducing the amount of potential interactions with a resource. Fail-Safe Defaults Design PrincipleThe Fail-Safe Defaults design principle pertains to allowing access to resources based on granted access over access exclusion. This principle is a methodology for allowing resources to be accessed only if explicit access is granted to a user. By default users do not have access to any resources until access has been granted. This approach prevents unauthorized users from gaining access to resource until access is given. Economy of Mechanism Design PrincipleThe Economy of mechanism design principle requires that systems should be designed as simple and small as possible. Design and implementation errors result in unauthorized access to resources that would not be noticed during normal use. Complete Mediation Design PrincipleThe Complete Mediation design principle states that every access to every resource must be validated for authorization. Open Design Design PrincipleThe Open Design Design Principle is a concept that the security of a system and its algorithms should not be dependent on secrecy of its design or implementation Separation Privilege Design PrincipleThe separation privilege design principle requires that all resource approved resource access attempts be granted based on more than a single condition. For example a user should be validated for active status and has access to the specific resource. Least Common Mechanism Design PrincipleThe Least Common Mechanism design principle declares that mechanisms used to access resources should not be shared. Psychological Acceptability Design PrincipleThe Psychological Acceptability design principle refers to security mechanisms not make resources more difficult to access than if the security mechanisms were not present Defense in Depth Design PrincipleThe Defense in Depth design principle is a concept of layering resource access authorization verification in a system reduces the chance of a successful attack. This layered approach to resource authorization requires unauthorized users to circumvent each authorization attempt to gain access to a resource. When designing a system that requires meeting a security quality attribute architects need consider the scope of security needs and the minimum required security qualities. Not every system will need to use all of the basic security design principles but will use one or more in combination based on a company’s and architect’s threshold for system security because the existence of security in an application adds an additional layer to the overall system and can affect performance. That is why the definition of minimum security acceptably is need when a system is design because this quality attributes needs to be factored in with the other system quality attributes so that the system in question adheres to all qualities based on the priorities of the qualities. Resources: Barnum, Sean. Gegick, Michael. (2005). Least Privilege. Retrieved on August 28, 2011 from https://buildsecurityin.us-cert.gov/bsi/articles/knowledge/principles/351-BSI.html Saltzer, Jerry. (2011). BASIC PRINCIPLES OF INFORMATION PROTECTION. Retrieved on August 28, 2011 from  http://web.mit.edu/Saltzer/www/publications/protection/Basic.html Barnum, Sean. Gegick, Michael. (2005). Defense in Depth. Retrieved on August 28, 2011 from  https://buildsecurityin.us-cert.gov/bsi/articles/knowledge/principles/347-BSI.html Bertino, Elisa. (2005). Design Principles for Security. Retrieved on August 28, 2011 from  http://homes.cerias.purdue.edu/~bhargav/cs526/security-9.pdf

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  • Create Sound and Video Presentation For Your Website

    The concept of web video production offers the business community an exciting opportunity to expand their reach. The technological advances in the speeds of internet transmission now make it possible to take the concept of marketing to another level. The availability of high quality video provides an efficient tool for business to reach an expanding customer base. This article will briefly discuss web video production.

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  • Revamp Websites With Custom Design

    The concept of web design encompasses the task of developing hypertext or hypermedia content which a user can access through the World Wide Web. Through web design websites are created. The concept entails more on designing rather than development, i.e. taking care of the graphic elements, look and feel and other aesthetic feature. It is different from professional web development which often concentrates on the technical aspect of the website.

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  • Legal Applications of Metamorphic Code

    - by V_P
    Firstly, I would like to state that I already understand the 'vx' applications for Metamorphic code. I am not here to ask a question related to any of those topics as that would be inappropriate in this context. I would like to know if anyone has ever used 'Metamorphic' code in practice, for purposes other than those previously stated, if so, what was the reasoning for using said concept. In essence I am trying to discover a purpose for this concept, if any, other than circumventing anti-virus scanners and the like.

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  • using an already proved lema/theorem/corollary in coq

    - by André Hincu
    I am trying to make a proof in Coq, and I would like to use a lemma already definded and proved by me. Is it possible for the following code? Lemma conj_comm: forall A B : Prop, A /\ B -> B /\ A. Proof. intros. destruct H. split. exact H0. exact H. Qed. Lemma not_conj_comm: forall A B : Prop, ~(A /\ B) -> ~(B /\ A). Proof. intros. intro. unfold not in H. apply H. use H0. In the above I want to use the fact that A /\B is the same as B /\ A in order to prove that ~(A /\ B) is the same as ~(B /\ A). Is it possible to use my proved lemma?

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  • Formal Languages, Inductive Proofs &amp; Regular Expressions

    - by MarkPearl
    So I am slogging away at my UNISA stuff. I have just finished doing the initial once non stop read through the first 11 chapters of my COS 201 Textbook - “Introduction to Computer Theory 2nd Edition” by Daniel Cohen. It has been an interesting couple of days, with familiar concepts coming up as well as some new territory. In this posting I am going to cover the first couple of chapters of the book. Let start with Formal Languages… What exactly is a formal language? Pretty much a no duh question for me but still a good one to ask – a formal language is a language that is defined in a precise mathematical way. Does that mean that the English language is a formal language? I would say no – and my main motivation for this is that one can have an English sentence that is correct grammatically that is also ambiguous. For example the ambiguous sentence: "I once shot an elephant in my pyjamas.” For this and possibly many other reasons that I am unaware of, English is termed a “Natural Language”. So why the importance of formal languages in computer science? Again a no duh question in my mind… If we want computers to be effective and useful tools then we need them to be able to evaluate a series of commands in some form of language that when interpreted by the device no confusion will exist as to what we were requesting. Imagine the mayhem that would exist if a computer misinterpreted a command to print a document and instead decided to delete it. So what is a Formal Language made up of… For my study purposes a language is made up of a finite alphabet. For a formal language to exist there needs to be a specification on the language that will describe whether a string of characters has membership in the language or not. There are two basic ways to do this: By a “machine” that will recognize strings of the language (e.g. Finite Automata). By a rule that describes how strings of a language can be formed (e.g. Regular Expressions). When we use the phrase “string of characters”, we can also be referring to a “word”. What is an Inductive Proof? So I am not to far into my textbook and of course it starts referring to proofs and different types. I have had to go through several different approaches of proofs in the past, but I can never remember their formal names , so when I saw “inductive proof” I thought to myself – what the heck is that? Google to the rescue… An inductive proof is like a normal proof but it employs a neat trick which allows you to prove a statement about an arbitrary number n by first proving it is true when n is 1 and then assuming it is true for n=k and showing it is true for n=k+1. The idea is that if you want to show that someone can climb to the nth floor of a fire escape, you need only show that you can climb the ladder up to the fire escape (n=1) and then show that you know how to climb the stairs from any level of the fire escape (n=k) to the next level (n=k+1). Does this sound like a form of recursion? No surprise then that in the same chapter they deal with recursive definitions. An example of a recursive definition for the language EVEN would the 3 rules below: 2 is in EVEN If x is in EVEN then so is x+2 The only elements in the set EVEN are those that be produced by the rules above. Nothing to exciting… So if a definition for a language is done recursively, then it makes sense that the language can be proved using induction. Regular Expressions So I am wondering to myself what use is this all – in fact – I find this the biggest challenge to any university material is that it is quite hard to find the immediate practical applications of some theory in real life stuff. How great was my joy when I suddenly saw the word regular expression being introduced. I had been introduced to regular expressions on Stack Overflow where I was trying to recognize if some text measurement put in by a user was in a valid form or not. For instance, the imperial system of measurement where you have feet and inches can be represented in so many different ways. I had eventually turned to regular expressions as an easy way to check if my parser could correctly parse the text or not and convert it to a normalize measurement. So some rules about languages and regular expressions… Any finite language can be represented by at least one if not more regular expressions A regular expressions is almost a rule syntax for expressing how regular languages can be formed regular expressions are cool For a regular expression to be valid for a language it must be able to generate all the words in the language and no other words. This is important. It doesn’t help me if my regular expression parses 100% of my measurement texts but also lets one or two invalid texts to pass as well. Okay, so this posting jumps around a bit – but introduces some very basic fundamentals for the subject which will be built on in later postings… Time to go and do some practical examples now…

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