klm connection in schiphol from toronto to london....

obviously both are non-schegen countries. i believe there is no need to go to passport or security for connection. But I noticed london flights depart in concourse D, which have both schegen and non-schegen flights. how is the concourse D divided between schegen and non-schegen so that they can't go to each other's gates? i am just worried the ams-lhr flight might be tricky since it's in concourse D.