The boundary value analysis is a technique for testing the boundary value of an equivalence class partition. A boundary value analysis identifies errors at the boundaries, opposed to within ranges in equivalence partitioning.
Example : Consider an input field in an application that can accept a minimum of 5 characters and a maximum of 10 characters. We were able to split our test cases into three equivalence classes composed of invalid and valid input. Then 5-10 is considered as valid and <4 and >10 is considered as invalid.
Test cases for application input field accepting numbers between 5-10 using boundary value analysis :
The valid partition : Between values 5-10 (For this test case, we will use the same test data as the input boundaries of the input domain, namely values 5 and 10).
The first invalid partition : <5 (The test data value for this case will be just below the edge/boundary of the input domain, i.e., value 4).
The second invalid partition : >10 (The test data value for this case will be just above the edge/boundary of the input domain, i.e., value 11).
