The success of mobile communication, shows that the interest in users to access the Internet or their official networks on the move. This mobility support may be needed for a single user or group of nodes called as movable sub networks. Network Mobility (NEMO) protocol developed by IETF enables the mobile nodes and networks to maintain connectivity to their network or Internet by change their point of attachment to from one access network to another. NEMO is an extension of Mobile IPv6, this works based on tunneling the data from home agent to mobile router. The Quality of Service provided by the NEMO is measured based on the routing mechanism it operates, hand off latency and the way of secured data transfer. Though the tunneling process ensures the security of data, the various nodes involved in NEMO are vulnerable as the network is wireless without a proper infrastructure. This article presents a survey on possible threats and solutions for NEMO protocol and its extensions. © 2005-2012 JATIT & LLS. All rights reserved.