New article on secret nodes is up here:
Secret nodes are network participants that run a node in the Enigma network and ensure secret contracts are executed in a privacy preserving manner. Nodes in Enigma network can be thought of as performing a function similar to miners in Bitcoin.
For secret nodes: how do I get selected and what is my incentive to contribute?
Enigma is an open source network — anyone can run a node to contribute to the network. In Discovery, the first iteration of our protocol, Enigma nodes have to run Intel SGX enabled devices (either their own hardware or cloud instances). Later iterations of Enigma protocol, which will introduce further improvements to secret contracts such as multi-party computation (MPC), will not be dependent on hardware. Furthermore, consensus nodes (when they become available after the launch of the Enigma chain) will not require any specialized hardware either.
The Enigma network uses a Proof of Stake model for worker selection, which means the probability of a worker node to be selected to run the next secret contract is proportional to the amount of ENG tokens staked by the node. This means that the greater your stake, the greater the cumulative rewards you can earn, as your likelihood to be sampled increases proportionally. There will also be a minimum amount of ENG required to run a staking node. That number is expected to be higher in the early days, and gradually to decrease to accommodate thousands and potentially tens of thousands of nodes.