PIM query

Hello all,
I have doubt in the following network topology.
Please tell me whether this is valid scenario?


     1            2         3            4
RCV------DR@RCV--------RP--------DR@SRC-------SRC
           |                       |
           |          5            |
           |-----------------------|


RCV 	: uses igmpv2 to join group G
DR@RCV 	: is DR at receiver.
RP	: Rendezvous point
DR@SRC 	: is DR at source
SRC     : multicasr sender
Number 1,2,3,4,5 indiate interface index just for 
simplifying the description.


NOTE THAT : "RP has route to SRC through DR@RCV."
and assume that DR@RCV does not switch to SPT b'cos
threshold configured in DR@RCV is infinity. 


I am confused about who sends periodic join(S,G)...DR@RCV or RP ?



AJay