IoT backend with Swarm and Ethereum smart contracts

Using Ethereum + Swarm as an IoT backend

• IoT gateways, which are relatively powerful LoRa/NB-IoT devices, may be used to push collected data to torrent-like Swarm file storage network via HTTP.
• Created file handles are stored in Ethereum blockchain using a smart contract named vendor.sol.
• By using Swarm as the storage service and Ethereum blockchain as the file explorer, it is possible to create a generic backend for IoT device manufacturers.

Smart contract interface

# check if device is present i.e. has ever pushed any data
function is_device_present (address device_id) public constant returns (bool result);
# get total device count
function get_device_count() public constant returns (uint count);
# enumerate device id's
function get_device_at_index (uint index) public constant returns (address device_address);
# get timestamp values containing data (for a specific device)
function get_device_timestamps (address device_id) public constant returns (uint[] timestamp);
# get stored file hashes (handles) with certain timestamp (for a specific device)
function get_device_data (address device_id, uint timestamp) public constant returns (string hash);
# push file hashes (handles) into the chain
function set_device_data (address device_id, string filehash) public returns (uint index, uint timestamp);
# event to log action
event log_action (address indexed device_id, uint index, uint timestamp, string filehash);

• How to deploy and run 'vendor' smart contract

Complete setup guide

• How to build Ethereum and Swarm binaries?
• What is Genesis block?
• How to setup a private Ethereum network?
• How to monitor the network?
• How to make transactions?
• How to start a private Swarm network?
• How to run Solidity (Remix IDE)?
• How to deploy and run smart contracts?