vRtrPimLdpPmsiCGrpSrcIfIndex 1.3.6.1.4.1.6527.3.1.2.50.2.14.1.11

The value of vRtrPimLdpPmsiCGrpSrcIfIndex indicates the interface index of the Ldp S-PMSI. This value will be non-zero integer value specific to the router.