Covering NEtwork MObility (NEMO) scenarios based on end-to-end mobility management protocols such as the Host Identity Protocol (HIP) is not straightforward. However, it has been demonstrated that HIP based NEMO solutions outperform NEMO Basic Support (NEMO BS), hence, HIP is being considered also for addressing NEMO scenario necessities. In this work we focus on the Registration Extension process of HIP, which is mandatory for providing reachability of HIP enabled mobile nodes. More specifically, we describe our proposal, the Bulk Registration process, which has been analytically modeled to show that it outperforms other registration approaches in more than 90% in terms of delay and signaling overhead. Obtained results are highly valuable for a common NEMO scenario where several nodes are present in a vehicle to control its operation.