The TE Router ID (reachable and stable IP address) of the
originator of the P2MP sub-group. In many cases, this will
be the ingress LSR of the P2MP tunnel and will be the
received signaled value as available in
cmplsTeP2mpTunnelDestSrcSubGroupOrigin.
When a signaling protocol is used, this object corresponds
to the Sub-Group Originator field in the SENDER_TEMPLATE
object.
This object is interpreted in the context of
cmplsTeP2mpTunnelDestSubGroupOriginType.