Wireless ad hoc network is a dynamic network with the commitment of cooperative nodes. Multicasting is intended for group communication that supports the dissemination of information from a sender to all the receivers in a group. The difficulties of ad hoc networks are the scarcity of bandwidth, short lifetime due to power constraint, dynamic topology caused by nodes' mobility, etc. These problems put in force to design simple, robust and energy efficient multicast routing protocols for this environment. In this paper, we discuss the architecture of different multicast routing protocols, address their deployment issues and provide a guideline for the researchers in this field.