The inherent characteristics and limitations of Internet of Things networks make it hard to avoid facing adverse network conditions. Addressing high performance in extreme situations still remains a challenge even for a standardized routing protocol like the IPv6 Routing Protocol for Low Power and Lossy Networks (RPL). No effective support is provided by the design of RPL to guarantee high network performance in the presence of such challenging conditions. To address such a compelling need, an innovative approach referred to as Dynamic-RPL is proposed in this research paper. With only limited in-protocol modifications to RPL, Dynamic-RPL provides effective support of dynamic topology management in a distributed manner. Seamless optimization of network topology is realized with dynamic topological adjustments to sustain high network performance and stability. It incorporates modified RPL topology establishment, customized RPL objective function and parent selection, a new dynamic topology management algorithm, and additional inter-routing support. The evaluation results demonstrated the ability of Dynamic-RPL to maintain high overall network performance irrespective of the adversity of ongoing network conditions. Considering varying-scale experimental setups, high QoS performance and low energy consumption were achieved without much increase in network overhead. Dynamic-RPL succeeded in adapting responsively with little time required to have the network performance successfully restored and network topology completely converged.