vRtrPimNgIfGrpSrcAsrtWnrMtrcPrf 1.3.6.1.4.1.6527.3.1.2.50.2.5.1.20

The value of vRtrPimNgIfGrpSrcAsrtWnrMtrcPrf indicates the ASSERT winner's preference associated by it's MRIB for the route towards the source or the RP.