The fact that the legal basis for SIS consists of separate instruments does not affect the principle that SIS constitutes one single information system that should operate as such.
Cé go bhfuil an bunús dlí do SIS comhdhéanta d'ionstraimí ar leithligh ní dhéanann sin difear don phrionsabal gur córas amháin faisnéise é SIS ar cheart feidhmiú mar aon chóras amháin.