  The tradeoff between cost of the access network and quality of offered
service to IoT devices, in terms of reliability and durability of
communications, is investigated. We first develop analytical tools for
reliability evaluation in uplink-oriented large-scale IoT networks. These tools
comprise modeling of interference from heterogeneous interfering sources with
time-frequency asynchronous radio-resource usage patterns, and benefit from
realistic distribution processes for modeling channel fading and locations of
interfering sources. We further present a cost model for the access network as
a function of provisioned resources like density of access points (APs), and a
battery lifetime model for IoT devices as a function of intrinsic parameters,
e.g. level of stored energy, and network parameters, e.g. reliability of
communication. The derived models represent the ways in which a required level
of reliability can be achieved by either sacrificing battery lifetime
(durability), e.g. increasing number of replica transmissions, or sacrificing
network cost and increasing provisioned resources, e.g. density of the APs.
Then, we investigate optimal resource provisioning and operation control
strategies, where the former aims at finding the optimized investment in the
access network based on the cost of each resource; while the latter aims at
optimizing data transmission strategies of IoT devices. The simulation results
confirm tightness of derived analytical expressions, and show how the derived
expressions can be used in finding optimal operation points of IoT networks.
