▁integr ator ▁( company ) ▁is ▁providing ▁an ▁enh ancement ▁to ▁a ▁customer ' s ▁existing ▁solution , ▁then ▁they ▁integrate ▁the ▁new ▁application ▁layer ▁and ▁the ▁new ▁database ▁layer ▁with ▁the ▁customer ' s ▁existing ▁application ▁and ▁database ▁layers . ▁After ▁the ▁integration ▁is ▁complete , ▁users ▁use ▁both ▁the ▁new ▁part ▁( ext ended ▁part ) ▁and ▁old ▁part ▁( pre - ex isting ▁part ) ▁of ▁the ▁integrated ▁application ▁to ▁update ▁data . ▁A ▁process ▁should ▁exist ▁to ▁exchange ▁data ▁imports ▁and ▁exports ▁between ▁the ▁two ▁data ▁layers . ▁This ▁data ▁exchange ▁process ▁should ▁keep ▁both ▁systems ▁up - to - date . ▁The ▁purpose ▁of ▁system ▁integration ▁testing ▁is ▁to ▁ensure ▁all ▁parts ▁of ▁these ▁systems ▁successfully ▁co - exist ▁and ▁exchange ▁data ▁where ▁necessary . ▁ ▁There ▁may ▁be ▁more ▁parties ▁in ▁the ▁integration , ▁for ▁example ▁the ▁primary ▁customer ▁( consum er ) ▁can ▁have ▁their ▁own ▁customers ; ▁there ▁may ▁be ▁also ▁multiple ▁prov iders . ▁ ▁Data ▁driven ▁method ▁▁ ▁A ▁simple ▁method ▁of ▁S IT ▁which ▁can ▁be ▁performed ▁with ▁minimum ▁usage ▁of ▁software ▁testing ▁tools . ▁Data ▁imports ▁and ▁exports ▁are ▁ex changed ▁before ▁the ▁behavior ▁of ▁each ▁data ▁field ▁within ▁each ▁individual ▁layer ▁is ▁investig ated . ▁After ▁the ▁software ▁collaboration , ▁there ▁are ▁three ▁main ▁states ▁of ▁data ▁flow . ▁ ▁Data ▁state ▁within ▁the ▁integration ▁layer ▁ ▁Integr ation ▁layer ▁can ▁be ▁a ▁middle ware ▁or ▁web ▁service ( s ) ▁which ▁acts ▁as ▁a ▁medium ▁for ▁data ▁imports ▁and