In this paper, we propose a security mechanisms for the Hybrid-Wireless-Mesh Protocol (HWMP). Our mechanisms is based on the Identity Based Cryptography (IBC). The motivation behind using IBC is that it eliminates the need to verify the authenticity of public keys. We have implemented the IBC technique to secure control message in HWMP, namely RREQ (Path Request) and RREP (Path Reply). In these Control messages, we are interested only by mutable (i.e. fields that an changing during control packet exchange). Through simulation experiments, we have evaluated the performance of our IBC-HWMP in terms of delay and control overhead. +Simulation results show that the IBC-HWMP does not induce a long overhead compared to the original HWMP protocol.