  The increased use of Internet of Things (IoT) devices -- from basic sensors
to robust embedded computers -- has boosted the demand for information
processing and storing solutions closer to these devices. Edge computing has
been established as a standard architecture for developing IoT solutions, since
it can optimize the workload and capacity of systems that depend on cloud
services by deploying necessary computing power close to where the information
is being produced and consumed. However, as the network scale in size, reaching
consensus becomes an increasingly challenging task. Distributed ledger
technologies (DLTs), which can be described as a network of distributed
databases that incorporate cryptography, can be leveraged to achieve consensus
among participants. In recent years DLTs have gained traction due to the
popularity of blockchains, the most-well known type of implementation. The
reliability and trust that can be achieved through transparent and traceable
transactions are other key concepts that bring IoT and DLT together. We present
the design, development and conducted experiments of a proof-of-concept system
that uses DLT smart contracts for efficiently selecting edge nodes for
offloading computational tasks. In particular, we integrate network performance
indicators in smart contracts with a Hyperledger Blockchain to optimize the
offloading on computation under dynamic connectivity solutions. The proposed
method can be applied to networks with varied topologies and different means of
connectivity. Our results show the applicability of blockchain smart contracts
to a variety of industrial use cases.
