Due to the recent development and advancement of communication technologies, healthcare industries are becoming more attracted towards information and communication technology services. One of the interesting services is the remote monitoring of patients through the use of a wireless body area network (WBAN), which enables healthcare providers to monitor, diagnose and prescribe patients without being present physically. To develop reliable and exible remote patient monitoring services, in this thesis, the current state-of-the art of WBAN and the limitations of current WBAN technologies are investigated in the healthcare domain. To this end, the relevant background, implementation challenges and limitations of WBAN are overviewed. The in-depth literature survey identifies the lack of a current WBAN architecture in terms of administrative control, static architecture, vendor dependency, traffic priority arrangements, resource utilization, secure data sharing etc. To find a solution to the limitations of WBAN, software-defined networking (SDN) is considered to be one of the promising solutions in this paradigm. However, the incorporation of SDN into WBAN has several challenges in terms of architectural framework, resource optimization and secure data sharing. In this thesis, an SDN-based WBAN (SDWBAN) architecture is proposed to incorporate the functionalities and principles of SDN on top of the traditional WBAN architecture to overcome the existing barriers of WBAN. The proposed communication model of the SDWBAN framework utilizes the sector-based distance (SBD) routing protocol for data packet dissemination. Furthermore, an application classification algorithm is developed to prioritize emergency applications over normal applications. The proposed architecture and communication model have been simulated and experiments are conducted in Castalia 3.2. The simulation outcome demonstrates enhanced performance in terms of the packet delivery rate (PDR) and the latency of the emergency applications in comparison to normal applications. For resource optimization, a mathematical model is developed to optimize the design of the control plane in the proposed SDWBAN framework. The purpose of the model is to reduce the unnecessary wastage of resources and find an optimal relationship among the number of controllers, SDN-enabled switches (SDESWs) and body sensors (BSs) which can potentially maximize network performance. The key factors in the proposed mathematical model encompass the number of controllers, ow resolution time and number of SDESWs and BSs. The specific number of controllers returned by the model is used in the proposed SDWBAN and experiments are conducted in Castalia 3.2. The simulation results reveal that the optimal number of controllers returned by our model produces an acceptable range of PDR and latency. Finally, a secure data-sharing platform is proposed for our SDWBAN framework. The platform is developed based on the cutting-edge blockchain technology and considers multiple entities such as healthcare professionals from various clinics, medical researchers and health insurers etc. The platform is implemented with a proof-of-concept (PoC) smart contract in Ethereum private blockchain using the Solidity programming language. The platform is validated in terms of time to execute functions in a data-sharing contract (DS-Contract) and hash-contract, the time to receive data packets from the gateway and the transaction time to run the smart contract. A low overhead is observed in the experiment which justifies the suitability of the platform to be used as a secure datasharing platform for SDWBAN.