Previous Works Motivation 上浒充通大￥ Main challenge and contribution SHANGHAI JIAO TONG UNIVERSITY Multicast group size Power-law This work distribution (Social network based) 1 Fixed Multicast Start point group size destination (X.Li's work [11]) distribution Uniform Rank-based model distribution (Social network based) 10Previous Works & Motivation Main challenge and contribution 10 Start point (X. Li’s work [11]) Multicast group size Multicast destination distribution Fixed group size Uniform distribution This work Power-law distribution Rank-based model (Social network based) (Social network based)