The NEMO Basic Support (NEMO BS) protocol provides a technique for enabling entire networks of IPv6 hosts to gain Internet access and remain reachable via constant, unaltered addresses whilst their underlying location in the Internet changes. In addition to individual hosts, this NEMO model also supports entire mobile networks connecting to other mobile networks, resulting in topologies known as Nested NEMO networks. In this paper we explain the inefficiencies that arise if NEMO BS is used to support this type of scenario and introduce our NEMO+ suite of protocols which are designed to optimise performance in Nested NEMO networks. We detail the Tree Discovery (TD), Network In Node Advertisement (NINA) and Reverse Routing Header (RRH) protocols that make up the NEMO+ suite and provide experimental evaluation results from a testbed comprising of our two distinct protocol implementation platforms (Linux and Cisco IOS). In addition we present simulation results based on scenarios of mass deployment of NEMO+ enabled mobile networks in order to determine the feasibility of our approach to efficiently support Nested NEMO networks.