Questions

It is a useful, memory-saving technique for multiprogrammed timesharing systems. A Reentrant Procedure is one in which multiple users can share a single copy of a program during the same period. Reentrancy has 2 key aspects: The program code cannot modify itself, and the local data for each user process must be stored separately. Thus, the permanent part is the code, and the temporary part is the pointer back to the calling program and local variables used by that program. Each execution instance is called activation. It executes the code in the permanent part, but has its own copy of local variables/parameters. The temporary part associated with each activation is the activation record. Generally, the activation record is kept on the stack.

Note: A reentrant procedure can be interrupted and called by an interrupting program, and still execute correctly on returning to the procedure.

Windows NT uses protection mechanism called rings provides by the process to implement separation between the user mode and kernel mode.

ICMP means Internet Control Message Protocol and is always coupled with the IP protocol (There are 2 ICMP variants one for IPv4 and one for IPv6.) echo request and echo response are the two operation codes of ICMP used to implement ping.

a.) Quality Assurance

Quality assurance is an activity that establishes and evaluates the processes that produce products. Quality assurance would measure processes to identify weaknesses and then correct them to continually improve the process: Eg. Code review.

b.) Quality Control

Quality control is a process in which the product's quality is compared with standards and corrective actions taken if required. Quality control activities focus on identifying defects in the actual products produced. Eg. Testing.

c.) Test Case

A test case is a unit level document describing the inputs, steps of execution and the expected result of each test condition for every requirement from the BRD. Testers determine whether the application is working correctly or not based on the test case that is being executed. A test case is marked as "Pass" if the application works as expected and is marked as "Fail" if otherwise. Test cases also aide in generating test status metrics.

d.) Test Condition

Test condition is the condition on which the test execution evaluates to pass or fail. Eg of a test condition: Set Password field should accept a mix of Alphanumeric and Special characters on mandatory basis and throw error message otherwise.

e.) Test Script

Test script is the set of instructions performed on the application to verify its functions.

f.) Test Data

Test data is the input data used to test a particular functionality. Eg: Username and password to test a login screen.

g.) Test Bed

Test bed is the environment on which the testing is done and includes the software and hardware set up that is required for testing the application.