9. RPL and multipath

So far, we've described RPL's set of mechanisms for setting up an upstream route for its preferred parent and the corresponding downstream route. To guarantee multipathing, RPL allows you to select parents other than the preferred parent: all parents.

All parents are designed to comply with the following rules:

• nodes belonging to the set of parents for a given node must have connectivity with it;

• the DODAG root must have a set of parents of size 0 ;

• a node that is not the root of the DODAG tries to maintain a parent set size greater than or equal to 1 ;...