  Today, the number of IoT devices in all aspects of life is exponentially
increasing. The cities we are living in are getting smarter and informing us
about our surroundings in a contextual manner. However, there lay significant
challenges of deploying, managing and collecting data from these devices, in
addition to the problem of storing and mining that data for higher-quality IoT
services. Blockchain technology, even in today's nascent form, contains the
pillars to create a common, distributed, trustless and autonomous
infrastructure system. This paper describes a standardized IoT infrastructure;
where data is stored on a DDOS-resistant, fault-tolerant, distributed storage
service and data access is managed by a decentralized, trustless blockchain.
The illustrated system used LoRa as the emerging network technology, Swarm as
the distributed data storage and Ethereum as the blockchain platform. Such a
data backend will ensure high availability with minimal security risks while
replacing traditional backend systems with a single "smart contract".

Cryptography and Security