Currently, providing 6LoWPAN fragmentation security is considered as one of the most critical issue since 6LoWPAN nodes are deployed in hostile environments and, therefore, are vulnerable to severe attacks. In this paper, we describe security threats to be observed in the 6LoWPAN fragments while fragments traverse across multiple hops towards the destination. Moreover, we explain the fundamental characteristics and security requirements of fragments in 6LoWPAN. Then, possible fragmentation security vulnerabilities and attacks in 6LoWPAN are identified. We also identified possible causes to fragmentation security threats in the 6LoWPAN. Finally, we propose a 3-tier secure end-to-end authentication (SEA) and message transmission protocol to overcome fragmentation vulnerabilities and prevent fragmentation attacks such as selective forwarding, sinkhole, wormhole, denial of service, sybil, replay, buffer overflow, node revocation and spoofed attacks in a large scale motionless 6LoWPAN. The proposed scheme assures 6LoWPAN node-to-stub node, stub node-to-edge router and edge router-to-edge router authentication along the way from source to destination.
