Feather forking as a positive force: incentivising green energy - PowerPoint PPT Presentation

Feather forking as a positive force: incentivising green energy production in a blockchain-based smart grid Antonio Magnani 1 Luca Calderoni 1 Paolo Palmieri 2 1 Dept. of Computer Science and Engineering University of Bologna, Italy 2 Dept. of Computer Science University College Cork, Ireland 1st Workshop on Cryptocurrencies and Blockchains for Distributed Systems, June 2018 A. Magnani (UniBo) Feather forking as a positive force CryBlock 2018 1 / 16

Outline Introduction 1 Design 2 System architecture Proof of Work vs Proof of Stake Feather Forking Transactions 3 Summary 4 A. Magnani (UniBo) Feather forking as a positive force CryBlock 2018 2 / 16

Introduction Goal Propose a smart grid architecture aimed at incentivising the production and distribution of green energy. Key aspect Introduce an ethical mechanism inside the blockchain: Discourages the production of non-renewable energy under certain circumstances Preserves the freedom of choice of smart grid stakeholders Idea Exploit a reverse application of the feather forking attack. A. Magnani (UniBo) Feather forking as a positive force CryBlock 2018 3 / 16

Design Architecture The collaborative architecture proposed is built over a network connecting: Energy Producers Distributors (at least) A regulator or a national energy authority Standard decentralised peer-to-peer structure: Persistent connection between peers Peers can join or leave the network dynamically Peers The peers are servers corresponding to energy production facilities or commercial energy distributors: Only nodes recognized by the energy authority participate to network The energy authority could provide dedicated hardware to the stakeholders A. Magnani (UniBo) Feather forking as a positive force CryBlock 2018 4 / 16

Design II Each participating node is a black-box Stakeholders are not allowed to tamper with the functioning of the server (they are not malicious) Each peer maintains a limited degree of anonymity The authority also participates actively to the network Blockchain transactions Only transactions to and from the energy grid (i.e., the reselling by distributors to final users is excluded) Mining reward = transaction fees All the actors are miners and they will try to minimise their transaction costs A. Magnani (UniBo) Feather forking as a positive force CryBlock 2018 5 / 16

System architecture A. Magnani (UniBo) Feather forking as a positive force CryBlock 2018 6 / 16

Proof of Work vs Proof of Stake The described scenario suggests solutions that are not based on the Proof of Work model but... Proof of Stake Introduces a number of drawbacks: Nothing-at-stake issue No currency = ⇒ The stake could only be based on the volume of energy produced/distributed Why prefer Proof of Work? Main drawback: significant amount of computation (energy) is wasted. Energy authority controls the global hash power The black-boxes are provided = ⇒ all peers have the same hashing power (i.e., no race for computational power) A. Magnani (UniBo) Feather forking as a positive force CryBlock 2018 7 / 16

Feather Forking I Feather forking ( FF ) is a modification of the more well-known punitive forking attack . Punitive forking attack Exclude someone from the blockchain through systematic forking of those blocks containing transactions from the blacklisted subject. Hard to carry out: the attacker needs the majority of the hash power. Feather Forking attack Crucial difference: the attacker announces that he is going to use his hash power α in order to fork the chain for a limited number of k blocks. A. Magnani (UniBo) Feather forking as a positive force CryBlock 2018 8 / 16

Feather Forking II Definition - Successful attack We define a successful feather forking attack, and we refer to it as FF k , the event when an attacker connects k + 1 consecutive blocks to a forked chain before other peers connect at least k consecutive blocks to the main chain. The probability for FF k is P ( FF k ) = α ( k +1) Attack succeeds Blackl. . . . ✗ block ✓ Attack fails Blackl. . . . ✓ block ✗ A. Magnani (UniBo) Feather forking as a positive force CryBlock 2018 9 / 16

Feather Forking III The probability of a successful attack is always marginal but other peers are aware that a targeted block has a P ( FF k ) chance of being orphaned. This attack can drive other peers to follow the same behavior. Best line of defence for impacted peers: pay a higher transaction fee . Change perspective Use this attack as a positive force: Energy authority may carry out FF to discourage non-renewable energy production (when it is not needed). Authority has knowledge of the overall hash power and it controls a considerable part of it. A. Magnani (UniBo) Feather forking as a positive force CryBlock 2018 10 / 16

Transactions Key aspects The black-boxes will be designed to mine independently of the reward No currency = ⇒ fees are also energy ECA could adjusts its hash rate according to the circumstances (or the type of energy) Only the transactions from the EPs to the ECA are subject to FF Sender Receiver Fee Feather Forking PubKey PubKey EP ECA ✓ ✓ ECA D ✗ ✗ Miner ECA ✗ ✗ Table: Classes of transactions. A. Magnani (UniBo) Feather forking as a positive force CryBlock 2018 11 / 16

Transactions First type: inputs energy to the grid The EP decides autonomously to add a transaction fee The fee will be earned by the peer who mined the block containing the transaction The source of the energy is declared Once the energy has been input into the grid, the type of energy is no longer defined (i.e., even for the fee) A. Magnani (UniBo) Feather forking as a positive force CryBlock 2018 12 / 16

Transactions Second type: emissions of energy to distributors The mining of blocks containing these transactions is carried out passively by any black-box A. Magnani (UniBo) Feather forking as a positive force CryBlock 2018 13 / 16

Transactions Third type: fees withdrawals The mining of blocks containing these transactions is carried out passively by any black-box After confirmation: the ECA will pay the peer an equivalent amount externally to the system A. Magnani (UniBo) Feather forking as a positive force CryBlock 2018 14 / 16

Conclusions Summary We introduced a novel blockchain-based system aimed at the regulation of energy production and distribution Specific focus was posed on the type of energy which the producer plugs in the grid. We discussed a tailored application of the feather forking attack designed to discourage the production of non-renewable energy. A. Magnani (UniBo) Feather forking as a positive force CryBlock 2018 15 / 16

Feather forking as a positive force: incentivising green energy production in a blockchain-based smart grid Antonio Magnani 1 Luca Calderoni 1 Paolo Palmieri 2 1 Dept. of Computer Science and Engineering University of Bologna, Italy 2 Dept. of Computer Science University College Cork, Ireland 1st Workshop on Cryptocurrencies and Blockchains for Distributed Systems, June 2018 A. Magnani (UniBo) Feather forking as a positive force CryBlock 2018 16 / 16