According to an embodiment, a communication control device includes a receiving unit, a generating unit, and an output unit. The receiving unit receives input of a binary tree in which each of leaf nodes has an index assigned thereto, and receives input of a node ID that enable identification of a leaf node belonging to a group. The generating unit generates set information indicating a set of a predetermined number of partial trees of the binary tree. Each partial tree includes only the leaf node identified by the node ID. The generating unit generates range information of the indexes assigned to one or more leaf nodes of each partial tree included in the set. The output unit outputs the set information and the range information at least to a communication device corresponding to a leaf node belonging to the group.