  Efficient flexibility and higher system scalability call for enhanced network
performance, better energy consumption, lower infrastructure cost, and
effective resource utilization. To accomplish this, an architectural
optimization and reconstruction of existing cellular network is required.
Network slicing is considered to be one of the key enablers and an
architectural answer of communication system of 2020 and beyond. Traditional
mobile operators provide all types of services to various kinds of customers
through a single network, however, with the deployment of network slicing
operators are now able to divide entire network into different slices each with
its own configuration and specific Quality of Service (QoS) requirements. In a
slice-based network, each slice will be considered as a separate logical
network. In this way, the infrastructure utilization and resource allocation
will be much more energy and cost efficient in comparison to traditional
network. In this paper, we provided a comprehensive discussion on concept and
system architecture of network slicing with particular focus on its business
aspect and profit modeling. We throughly discussed two different dimensions of
profit modeling, so called Own-Slice Implementation and Resource Leasing for
Outsourced Slices. We further addressed open research directions and existing
challenges with the purpose of motivating new advances and adding realistic
solutions to this emerging technology.
