An efficient and scalable multicast routing protocol for ad hoc networks is proposed. Network Sender Multicast Routing Protocol (NSMRP) is a mesh based protocol. A central node called mesh sender (MS) is selected periodically from among the group(s) sender(s) to create one mesh in order to be used in forwarding control and data packets to all multicast group(s) member(s). One invitation message will be periodically flooded to all group(s) member(s) by MS to join the group(s). NSMRP is evaluated by simulation, and the simulation results show that NSMRP is achieving better performance and low overheads by varying the maximum mobility speeds or increasing the number of multicast groups or senders.