Connected devices on the Internet which are commonly known as Internet of Things (IoT) are increasing continuously at an alarming pace. There should be adequate network infrastructure facilities to handle the data explosion. One challenge is that IoT devices are globally distributed. The network infrastructure should be able to reach all these globally distributed devices. This is an enormous challenge and a huge investment in infrastructure by any single service provider. Since users are subscribed to many different service providers, and are globally distributed, it is impossible for each service provider to have its own separate network to serve its own subscribers. As new technology emerges, the hardware becomes quickly obsolete leading to huge recurring costs by each service provider [31,7]. A new sharable architecture is needed which is flexible to the changing demands of the subscribers of each service provider. This is particularly the case when the number of subscribers are changing for each of the service providers. The demand for the network resources will always be dynamically changing. Service providers will be able to borrow resources from the sharable network architecture and also relinquish those resources based on the demand of its subscribers. As a result, sharable architecture would ensure that adequate resources are allocated to the service providers based on their current needs, and plan to reserve resources for future predicted needs. Another key issue is the network reconfiguration required in order to accommodate changing traffic characteristics such as bandwidth and delay requirements [10]. The security and service provisioning policies will keep on changing with time as new business applications are added to serve users on the network [1]. Packet handling policies have to be modified and high layer processing may have to be incorporated to newly added traffic [18]. As a result the location of the firewalls, load balancers, and other special purpose gateways have to be changed based on new policies. Such reconfiguration will be an issue in the shared network scenario when multiple service providers will be using a common network infrastructure. Because of all these concerns, isolation of network resources and strict confidentiality must be maintained between service providers. This will be made possible through newly developing technologies based on software defined networks (SDN) and network function virtualization (NFV). In this work, futuristic SDN and NFV architectures are discussed. Cost analysis is performed to analyze the benefits of such sharable SDN and NFV based network architectures.