Boundary value analysis (BVA) is an extension of equivalence partitioning but can only be used when the partition is ordered, consisting of numeric or sequential data.
The minimum and maximum values ( or first and last values) of a portion are its boundary values.
As an example, consider a printer that has an input option for the number of copies to be made, from 1 to 99. To apply boundary value analysis, we will take the minimum and maximum (boundary) values from the valid partition (1 and 99 in this case) together with the first or last value, respectively, in each of the invalid partitions adjacent to the valid partition (0 and 100 in this case). In this example, we would have three equivalence partitioning tests (one from each of the three partitions) and four boundary value tests.
