What is meant by flow specification?

- There are many problems concerning the flow specification. 

- There are limited options for the provider for mitigation of the DDoS attacks that take place internally. 

- These can be categorized in to three different categories:

Ø  BGP (border gateway protocol) destination black holes

Ø  BGP src/ uRP

Ø  ACLS

- The basic idea is to make use of the BGP for the distribution of the flow specification filters. 

- This helps in dynamic filtering in the routers. 

- The flow specification rules are encoded according to the BGP NLRI address family. 

- The flow spec NLRI is used by the BGP as its opaque key is used as an entry key for its database. 

- The extended communities are used for specifying the actions such as accepting, discarding it, rate limiting, sampling, redirecting and so on. 

- The source/destination prefix and the source/destination port are matched in combinations according to the packet size, ICMP type/co9de, fragment encoding, DSCP, TCP flag and so on. 

- For example, the TCP ports 80…90 are matched with 192.168.0/24. 

- The flow specification trust model uni casts the routing advertisements for controlling the traffic. 

- Filter is considered as a hole for the traffic that is being transmitted to some destination. 

- Filter is accepted when it is advertised for the destination by the next hop. 

- Filters with various flow specifications are available today.

- The major benefit of the flow specifications is the filters with the fine grain specification which make it easy for deploying and managing the BGP. 

- The trust and the distribution problems are solved by the BGP. 

- ASIC filtering in routers is leveraged. 

- This is another major benefit of flow specifications. 

Apart from the benefits, there are various limitations of the flow specifications as mentioned below:

Ø  There is no update level security in the BGP.

Ø The statistics and the application level acknowledgement are not well defined.

Ø  The flow specifications work only for those nodes for which the BGP has been enabled.

Ø  Beyond routing the BGP payload has to be overloaded.

Ø  There are various operational issues between the security operations and the network operations.

Ø  The threat information cannot be gathered in one place.

- The integration of the flow specifications was announced by various security vendors. 

- The DDoS attacks are experienced by a large number of customers. 

- The DDoS attacks are now massive and have put the network infrastructure at risk apart from the end customer. 

- Congestion problems occur at both the exchange and the backbone. 

- The attacks of long durations add to the cost of bursting and circuit congestion problems. 

- Depending up on the size of the attack the POP has to be isolated.

- VoIP is also affected. 

- These attacks have negative economic effects as the cost of the operations has been increased. 

- This has led to a degradation of the business. 

- Measures such as firewall filtering and destination BGP black-holing have proved to be insufficient in preventing the attacks. 

- These methods are slow since it is required to log-in and configuring the devices. 

- The configuration has to be constantly. 

- The traffic is terminated to some destination. 

- This affects the availability. 

- The black hole routes are removed by constantly changing the configurations. - Earlier version of the flow specifications had many bugs. 

- There were some limitations on the performance. 

- However, it provided arbor support for the actions of the flow specifications. 

- It does not provide multi–vendor support. 

- To some extent it provides the mitigation facility for the attack that occurred at the source. 

- The collateral damage is eliminated for both the carriers and supports the change in the matching criteria. 

What is meant by Deadlock? List the necessary conditions for arising deadlocks?

Consider two competing processes or actions in a situation where both of them wait for each other to be done and so neither of them ever finish. Such a situation is called a deadlock. 

- When the number of competing processes is exactly two, then it is said to be a ‘deadly embrace’. 

- The two involved competing actions tend to move towards some sort of tragedy which might be mutual extinction or mutual death. 

"In operating systems a situation occurs where two threads or processes enter the waiting state at the same time because of the resource that they both want is being used by some other process that also in waiting state for some resource being held by another process in waiting state and so on". 

- It so happens that the process is then unable to change its state since the resources it requires are being used by the other processes which is then keeping the process in waiting state indefinitely. 

- The system is now in a deadlock. 

- Systems such as the distributed systems, parallel computing systems, multi-processing systems face the problem of being in a deadlock quite often. 

- This is so because here the hardware and software locks are purposed for handling the resources that are shared and implementing the process synchronization. 

- Deadlocks may also occur in telecommunication systems because of the corrupt signals and their loss rather than resource contention. 

- A deadlock situation can be compared to problems such as that of the catch-22 or chicken or egg problem. 

- A deadlock can also occur in a circular chain pattern. 

- For example, consider a computer having 3 processes and corresponding 3 CD drives i.e., one held by each process. 

- Now all the three processes would be in a deadlock if they all request another drive.

Conditions for a Deadlock to arise

There are certain conditions that should be there for a deadlock to arise:

1. Mutual exclusion: There has to be at least one resource that cannot be shared. So that only one process would use at any given time.
2. Resource holding (or hold and wait): There should be at least one resource held by a process that in turn should be request more resources that are being held by other processes.
3. No preemption: Once the resources have been allocated, they should not de-allocated by the operating system. The condition is that the process holding the resource must release it voluntarily.
4. Circular wait: A circular chain of processes must be formed as explained in the earlier example.

"These 4 conditions for deadlock are collectively called the ‘Coffman conditions’. If any of these conditions is not met, a deadlock can’t occur".

- Handling a deadlock is an important capability of the operating systems. 

- However, there are many modern operating systems that still cannot avoid deadlocks. 

- On occurrence of a deadlock many non-standard approaches are followed by different operating systems for handling it. 

- Many of these approaches try to avoid at least one of the Coffman conditions (generally the 4^th one). 

- Below we discuss some of the approaches:

1. Ignoring deadlock
2. Detection
3. Prevention
4. Avoidance

- There is a second kind of deadlocks called the ‘distributed deadlock’ and it is common where concurrency control is used or we can say in the distributed systems. 

What are main features of TestComplete?

Many of the software applications are being written as web–based applications that can be run in a browser. The measure of effectiveness with which these applications are tested varies from organization to organization. 

- Test complete automated testing tool offers the answer to this demand. 

- For tests such as regression tests, responsiveness can be generated only through automated testing tools as such. 

- Automated testing is the way to provide many benefits including repeat-ability and speed of the test execution. 

- Test automation is known to induce long term efficiency in a software system or application.

- Developers also get a rapid feedback and can carry out unlimited iterations of the tests.

- Reporting gets customized and finding defects that were missed during the manual testing becomes easy.

-  However, automation always does not prove to be advantageous.

Features of TestComplete

Test complete  testing tool comes with certain features which we shall state now:

1. Keyword testing: This tool comes with a keyword–driven test editor that is built– in and consists of many keyword operations corresponding to the appropriate automated testing actions.
2. Test record and play back: This tool records the key actions which are required to play back the test. All the actions other than the required ones are then discarded.
3. Full featured script editor: This is another built – in editor using which the test scripts can be written manually. This editor comes with some special plug – ins that provide further assistance.
4. Script debugging features: This feature lets you stop before every statement that can be executed so that you can keep a track of what is going on and make changes accordingly.
5. Access to properties and methods of the objects: The names of all the visible elements can be read by this tool including internal elements of the following applications:

a)   Delphi

b)   C++builder

c)   .net

d)   WPF

e)   Java

f)    Visual basic etc.

Also this tool enables the access to values through test scripts so that they can be verified and used in the tests.

6. Unicode support: Tool has a Unicode character set support which enables the user to test the applications that are non – ASCII and use characters such as Hebrew, greek, Arabic, katakana and so on.
7. Issue–tracking support: This tool comes with issue tracking templates which can be deployed for the creation as well as modification of the items that reside in issue – tracking systems. The tool currently provides support for the following:

a)   Microsoft visual studio 2010,2008 and 2005 team system

b)   Bugzilla

c)   Automated QA AQdev team

8. Open architecture (COM based): An open API, COM interface forms the basis for the test complete’s engine. This makes this tool independent of the source – language and enables it to read the debugger info. It can use this info during run time via debug info agent of test complete.
9. Test visualizer: This feature of test complete lets you take screen shots of the test recording as well as play back thus allowing you to make comparisons among the actual as well as the expected screens during the run time.
10. Support for plug–ins: This feature allows the third party vendors to connect with test complete via their software systems and applications. 

How does story board testing in IBM Rational Functional Tester work?

IBM’s rational functional tester is counted among the best functional testing tools available till date. The functional testing capabilities can further be extended with the help of the SDK proxy. This can be done either manually or with the assistance of the Proxy SDK wizards. 

Introduction of the rational functional tester in the field of software testing has given a new significant direction to the functional testing. The following are the updates that were made then:

1. The visual test representation for the creation of no code test was enhanced via the following two ways:

a)   Dragging and dropping the controls in to the test scripts.

b)   Story board test representation.

2. The integration with the following was updated:

a)   IBM rational quality manager express edition and

b)  IBM rational quality manager standard edition v2.0 and v1.0.1.

Support for multiple project area was extended in the execution adapter and IBM rational quality manager was provided with the support for keywords.

3. New integration were made with the IBM rational team concert:

a)   Assets were bound to be managed within the SCM.

b)   IBM rational team concert V2.0 was added as an optional feature to the rational functional tester.

4. Packaged applications as well as environment support were expanded.

What is Story board testing in IBM Rational Functional Tester?

- Story board testing has been introduced as a completely new and visual approach to the automation of the actions performed by the test scripts.

- The story board testing comes with a three pane view which provides the following:

1. Description of the test actions in a natural language.
2. Screenshots of the screen that is currently being tested. Also if the control is to be used further then it is highlighted.
3. Script flow is displayed in the story board view which shows all the thumbnails of the all the screens that were accessed during the course of the test in an order of sequence.

- This testing approach gives a significant simplification of the test script editing and authoring. 

- The natural language is used all along the testing process along with the screen shots so as to provide the testers an easy way for understanding the flow of the test. 

- The test can be edited from this view as well. 

- You can carry out the following things in the story board testing:

1. Insert verification
2. Execute data driven commands
3. Insert java code

- The feature of story board testing in IBM rational functional testing does not come at the expense of the traditional testing approaches. 

- This testing approach can be considered to be a mere overlay of the java test script like it has always been known to have existed.  

- Users who are very well familiar and understand the IBM rational functional tester can go on with the story board testing as they used to do directly with the test script. 

- Story board testing approach has been accelerating the test creation by keeping it quite simple to read and edit the tests and open the test automation. 

- The story board testing approach was first introduced in the version 8.1 of the IBM rational functional tester.

- This approach did play a big role in enabling the testers in editing the test scripts by playing against the screen shots of the application captured by the rational functional tester. 

- Before this feature was included in the rational functional tester, the scripts were edited by the testers just by modifying it.

What is a Silk Test Test plan? What are the types of text lines in a test plan file?

A silk test plan consists of large amounts of data as well as information based on which are the details of the plan which in turn will be used in the organization and the development of the software system or application. 

It has three basic qualities as mentioned below:

1. Well structured
2. Hierarchical
3. Ideal model

A silk test test plan constitutes of two parts which are entirely different:

1. First part consists of an outline which gives a detailed description of the all the requirements of the testing process.
2. Second part consists of a statement which establishes a relationship between the outline of the first part and 4test scripts as well as test cases which are bound to implement the requirements defined above.

What is a Silk Test Plan?

- Test plan helps in achieving a guided way for the creation as well as execution of the test cases. 

- A new test plan can be created by following the below mentioned steps:

1. Go to the file menu and then click on new option.
2. From the drop down list that follows select test plan and hit OK. You will get a test plan window. Fill in the required fields and click OK.

- This is a known fact that silk test specializes in the field of functionality as well as regression testing and has been a known product when it comes to web, java or windows based applications. 

- Silk test provides you with two ways for defining or creating the automated tests:

1. By using the record test case command for recording the actions and the verification of steps.
2. Using visual 4test scripting language by writing the test cases manually.

- Test plans in silk test are stored as ‘test plan (.pln)’ file type. 

- This file type is sometimes used for making combinations of the test scripts. 

- The basic purpose of a silk test test plan is to provide a frame work for the testing process and also for the organization and maintenance of the testing requirements. 

Benefits of using a Test Plan

Using a test plan has following benefits:

1. With test plan you have a chance to implement top down approach for defining the testing requirements, developing thoughts and refining the requirements.
2. Attributes can be assigned to individual tests or group of tests.
3. Redundancy is reduced single only actually implementing statements are allowed.
4. Can be used as a comprehensive inventory of requirements consisting of most general as well as specific requirements.

What kind of text lines are there in a test plan file?

Test plan file consists of 5 types of text lines that we have described below:

1. First type of text lines are the comments which are usually marked in green color.These types of text lines provide commentary type of information regarding the test code.
2. Group Description: This type of text lines are represented in bold black color. Furthermore, they are included so as to provide a description of a group of tests rather than describing individual tests. Usually, a test plan consists of many tests which are then grouped in to multiple levels of various groups.
3. Test Description: This type of text lines are written in blue color and are meant for showcasing the description of the individual tests only.
4. Test plan statement: This type of text lines in a test plan file provide information regarding the relations to the following elements:

a)   Test cases

b)   Link scripts

c)   Test data

d)   Closed sub test plans

e)   Include files to a test plan.

These are marked in red color.

5. Open sub plan file marker: These text lines are marked in magenta color and thus providing info regarding relations to link sub test plans with the master plan.

What is the difference between functions and actions in QTP?

Functions and actions are two different aspects of quick test professional. In this article we will talk regarding the two and see what the differences between them are. 

What are functions in QTP?

- In most of the cases you may need to use some segments of code again and again in your tests. 

- In such a case a user defined function can be created which will not only reduce the length of your tests but will also make it easier to be designed, read and maintained. 

- The created functions can consist of the following:

1. Sub routines,
2. Modules
3. VBScript functions and so on.

- Three simple tests need to be followed if a function is to be used in the test from a library:

1. For creating a new function you can select new function library from the file menu. This cause a new tab to open up in the quick test professional window. You can even opt for multiple tests in the same file.
2. Next you need to save the function with extension “.qfl” and associate the appropriate library with that particular function. “Associate function library” option can be accessed from file menu.
3. Now the third step is to invoke the function using the usual simple function call. Quite advanced or sophisticated functions can be generated using DCOM and COM.

What are actions in QTP?

- Whenever you have a piece of code at your disposal you get two options in quick test professional i.e., to either turn it in to a function or a reusable action.

- When the quick test 9 was introduced by the mercury, an argument was made in the favor of the functions for making them more compelling by the means of multi document interface. 

- Many function libraries can be used at once but still mostly one test is used. 

- If you want a reusable action to be edited, the current test has to be shut down. 

- Then you need to open the test in which you want to make the changes, make the changes and then save and close. 

- Later, the original test can be re-opened.

Differences between Functions and Actions in QTP

Now we are stating below some very basic differences between the functions and actions in quick test professional:

1. Passing of Data: 

Functions can access a variety of objects advance as well as primitive like arrays, test objects (such as frames, pages and so on.) and dictionary objects. But this is not the case with the actions rather they can accept only primitive kind of data types such as parameters like integers, strings and so on.

2. Use of Resources: 

Each action is provided with the following basic things:

a)   A folder

b)   3 separate VBS files

c)   A subfolder for keeping snapshots

d)   A certain amount of load time

e)   An excel spreadsheet and

f)    A local object repository.

On the other hand a function consists of only the code and nothing else.

3. API: 

For functions, the function libraries can be attached to the test scripts through the API of the quick test professional. As for the actions the insertion of the calls in the existing actions is not possible through the API of the quick test professional rather it can be done only through the interface.

4. Return Values: 

Actions return the values which are quite difficult to be read in syntax as well as understand. On the other hand the return values of the functions work well and similarly in all the languages.

With actions your test can be divided in to business processes or logical units along with the scripts that are more efficient as well as modular.

Explain Quick Test Professional (QTP) Testing process?

The quick test professional is a software package that facilitates both the test automation as well as the software testing. To be an expert in quick test professional it is important that you understand both the test automation and software testing using the quick test professional. 

When the software testing process is carried out using the quick test professional it is referred to as the quick test professional test process. By now you must have got it that the emphasis of this article is on the same testing process. 

To say the quick test professional testing process constitutes of the following steps as mentioned below:

1. Configuring of the record and run settings
2. Creating an object repository (this step is optional is many cases)
3. Creating the basic automation scripts
4. Editing or enhancing the script
5. Executing the script
6. Debugging the script
7. Analyzing the results
8. Summarizing the results (this includes tracking the discovered defects and generating the report)

Major stages of the QTP testing process

1. Analyzation of the application

- This is the first test and is aimed at finding your testing needs. 

- This phase involves the type determination of the development environment of your application i.e., whether it is a web application or a windows application. 

- In either of the cases, you will need to load your quick test professional software with appropriate add ins. 

- There are available separated add – ins for both the web type and windows type applications. 

- These add – ins are required since they only give the power to quick test professional to identify as well work with the objects present in the application. - Next thing to determine are the business processes and functionality required. 

- For determining these two things you need to think about what your customer will do with the application. 

- The required business processes are then divided in to smaller groups or units and the actions based on these units are created. 

- This is done so because with smaller modular actions it becomes easy to read, follow and maintain the tests in the long term.

2. Preparation of the testing infrastructure: 

- Based on the needs that you determined in the first phase, the resources required are determined in this second phase. 

- The resources are either obtained or created as required. 

- The resources may include the following:

      a)   Object repositories along with the test objects.

      b)   Function libraries along with the functions that add to functionality of the quick test professional and so on.

- Also in this phase the settings of the quick test professional are configured as per the tasks need to be performed.

3. Building of the tests and addition of the steps to them: 

- By now the testing infrastructure is complete and now you can start developing your tests. 

- Any number of empty tests can be created and actions can be added to them so as to form the testing skeletons. 

- Relevant actions can be associated with the corresponding object repositories.

- Relevant tests can be associated with the function libraries. 

- Steps can be inserted with the help of key words and test preferences are also considered.

4. Enhancement of the test: 

- This phase includes insertion of the checkpoints so that you can easily search for a specific value of object, page or text etc and know whether or not your application is functioning properly.

5. Debugging, execution and analyzation of the test: 

- This phase ensures that the application is working without encountering any interruption. 

- Only if a test is running properly, it can correctly check the behavior of the application.

6. Reporting of the defects: 

- The defects discovered can be reported to the quality center if you have it installed on your machine. 

What are Virtual Objects in Quick Test Professional?

- The concept of the virtual objects in quick test professional comes in to light only when a failure in the identification of the object is encountered or some error is generated like “object not found”. 

- This happens because even after recording the actions during the time of play back, the quick test professional is experiencing some difficulties in the process of recognition of the object and this causes the whole script to fail. 

- A certain kind of object has been created in quick test professional in order to resolve the issues of the object recognition which has been termed as the “virtual objects”. 

- In some cases it happens that the quick test professional is unable to recognize the area of the object and therefore some other wizard is used for mapping the area of the object called the “virtual object wizard”. 

- All the virtual objects that are created during the course of object recognition are stored in the virtual object manager. 

- After the quick test professional has learned about the virtual object, it can record on the actual object very well. 

- A virtual object can be created easily by going to the tools menu, then selecting the virtual object list and then finally clicking on the new virtual object option. 

- Even though the virtual objects are very helpful there are some points about virtual objects to be noted:

1. It is not possible to use the object spy on a virtual object.
2. Only recording operation can be performed on virtual objects.
3. You cannot treat labels and scroll bars as virtual objects.

- For disabling the virtual objects mode, simply go to the tools drop down list, and then go to options, then general, then check the option which says “disable recognition of virtual objects while recording”. 

- Using virtual objects is just one way of handling the issues of object recognition. The other two are:

1. Analog recording and
2. Low level recording.

- Basically, the virtual objects help in the recognition of the objects that do behave like standard objects but still cannot be identified by the quick test professional. 

- Such objects are mapped to standard classes with the help of virtual object mapping wizard. 

- The user actions on the virtual objects are emulated by the quick test professional during the run session. 

- The virtual object is portrayed as a standard class object in the test results. 

- The virtual object wizard allows you to select the standard object class to which the object has to be mapped and then the boundaries of the virtual object can be marked with the help of the cross hair pointer. 

- After being done with this, a test object can be selected to be the parent of the virtual object. 

- The group of all virtual objects stored under one descriptive name is termed as the virtual objects collection. 

- While using the virtual objects during a run session always make sure that the size and location of the application window are exactly same as they were in the recording mode. 

- If it is not taken care of the coordinates of the virtual object may vary affecting the success of the whole run session. 

- Another point to be noted is that it is not possible to insert any check points on a virtual object. 

- For performing an operation on the active screen on a virtual object it is required that you first record it, save its properties in the description in the object repository.