he main issues and discusses possible solutions for 5G and blockchain in healthcare applications. 7.5.1 RESOURCE ALLOCATION CHALLENGE Computational and QoS requirements for each request need to be allocated physical resources that fulfill both requirements. The decision on where to place the task is the responsibility of the network orchestrator. The orchestrator may allocate com- putational resources on MEC servers or the cloud according to the availability of resources on MEC servers and on QoS requirements. Furthermore, other factors, such as task priority and energy consumption, can affect the allocation. Task priority implies how critical the task is, and therefore blocking high-priority tasks should be minimized. Minimizing energy consumption is an important factor to consider, espe- cially since the power capabilities of healthcare IoT devices are limited. Orchestrator architectures can be classified as centralized, such as in [16-18], or decentralized, such as in [19, 20]. Centralized orchestrators are typically placed as cluster heads for a group of base stations or at the core network. In this architecture, the orchestrator receives requests from several base stations and decides which MEC server they should be allocated to or whether the cloud best serves their requests. In the case of a decentralized orchestrator, the allocation decision is taken collabora- tively by MEC servers. Each server broadcasts its status to the other servers in the network SO that no server is overloaded, and the total number of requests satisfied is maximized. The advantage of using centralized orchestration is that it manages 5G Wireless Communication System in Healthcare Informatics requests and balances network loads easily, transfers less data over the network, and can be implemented over the current infrastructure with simple modifications. The problem with centralized orchestrators is a single point of failure. The decentralized architecture eliminates the single point of failure but overloads the network with a broadc