Best Practice to Assign Network

Hi Experts,

I have a question - What is best practice to Assign networks. Is it Header assignment or Activity Assignment.

I have a requirement which asks for a WBS Level Cost and Revenue posting while settlement. I followed the standard design of having a 1st level WBS and assigned a Network to that. Also have 2nd level WBSs linked to 1st level WBS, which have the activities. Is this suffice the settlement requirement.

Thanks

Rajesh