The existing LTE network architecture dose not scale well to increasing demands due to its highly centralized and hierarchical composition. In this paper we discuss the major modifications required in the current LTE network to realize a decentralized LTE architecture. Next, we develop two IP address mobility support schemes for this architecture. The proposed solutions can handle traffic redirecting and seamless IP address continuity for the nodes moving among the distributed anchor points in a resource efficient manner. Our approaches are based on the SDN (Software Defined Networking) paradigm which is also one of the most important candidate technologies to realize 5G mobile networks. We extend the NS3-LENA simulation software to implement a decentralized LTE network as well as the proposed IP mobility support schemes. The evaluation results show that the proposed solutions efficiently fulfill the functionality and performance requirements (e.g., latency and packet loss) related to mobility management.