-After we have built our system, verification and validation - -2
-is that phase of software development that aims to - -3
-check that the software system meets its specification and - -4
-fulfills its intended purpose. More precisely, we can look - -5
-at verification and validation independently. And validation is the - -6
-activity that answers the question did we build the - -7
-right system. Did we build the system that the - -8
-customer wants? That will make the customer happy. Whereas verification - -9
-answers a different question which is did we build the system - -10
-right. So given a description of the system that is the one - -11
-that we derived from the customer through the collection of requirements - -12
-and then design and so on, did we build a system that - -13
-actually implements the specification that we defined? And when we look - -14
-at verification there's many, many ways of doing verification and in fact - -15
-in the mini course number four we will cover verification extensively. The - -16
-only thing I want to mention here is the fact that verification - -17
-can be performed at different levels. In particular, it can be - -18
-performed at the unit level in which we test that the individual - -19
-units work as a expected. Can be performed in the integration level - -20
-in which what we test is the interaction between the different units. - -21
-So we want to make sure that the different modules talk - -22
-to each other in the right way. And finally, there is system - -23
-testing in which we test the system as a whole and we - -24
-want to make sure that all the system, all the different pieces - -25
-of the system work together in the right - -26
-way. And this is also the level at which - -27
-then we will apply validation and some other - -28
-testing techniques like stress testing or robustness testing and - -29
-so on. And as I said I'm not going to say anything more on this topic because - -30
-we will cover verification, and validation, and testing in - -31
-particular in great details in mini course number four. -- cgit 1.4.1