For large-scale multimedia distributions, multicast is the preferred method of communication. ASM (Any Source Multicast) and SSM (Source-Specific Multicast) are the two types of multicast used. ASM is designed for either many-to-many or one-to-many communication. SSM is derived from ASM. SSM is used when only one session member is allowed to send data. An example use of SSM could be an IPTV broadcasting system over fixed or mobile network. The paper deals with describing hierarchical aggregation for feedback transmission in SSM. For the purpose of hierarchical aggregation, multicast receivers are organized into a tree structure. We present a tree structure consisting of end and summarization nodes. End nodes act as multicast receivers and summarization nodes perform feedback aggregation. The proposed MFCP (Multicast Feedback Control Protocol) is used to establish the tree structure and to exchange signalization needed for the feedback hierarchical aggregation.