Task execution based on hierachy Level

Hello Guys,

I have a hierarchy with 2 Levels (L1 & L2; L2 is a subnode belonging to L1) and I want to oblige the users to execute the consolidation monitor task only based on Level 1,

what is the best solution into EC-CS? A validation, authorisation settings, others...

thank you in advance for your help

Best regards

Pascal