While Shardeum does not want to reinvent the wheel with regard to its smart contract platform, we recognize short-sighted fixes and improvements when it comes to security are bad ideas. In fact, Shardeum strongly believes in solving the trilemma issue at the layer 1 level instead of solving such sensitive issues at a layer 2 level or via side chains. That way, the ecosystem, which will host a ton of resources, will be extremely secure at the root level. This would, in turn, reinforce the security of projects deployed on top of the native security mechanisms such projects will employ to prevent hacks and other types of security attacks.
Shardeum will use a combination of two consensus algorithms, namely proof of stake (PoS) and proof of quorum (PoQ). Proof of Quorum means to generate a receipt showing that a majority of the consensus group has voted for the transaction. Each node in the consensus group signs the transaction hash and gossips it to other nodes in the consensus group. Nodes collect these votes, and when the number of votes is more than 50%, these votes form a receipt that can prove consensus on the transaction
Staking native coins will be mandatory for validators to participate in the transaction validation process in return for rewards. Nodes that act maliciously will be slashed or penalized. Note, the staking amount will be determined when we get closer to the mainnet however you can expect it to be reasonable enough to limit bot attacks. Proof of Quorum, in a nutshell, allows the network validators of a transaction to approve it only if it receives more than 50% of votes which is then followed by batching such transactions to blocks. And a key element with respect to security and scalability is, Shardeum introduces ‘standby nodes’ to randomly rotate ‘validator/consensus nodes’ in and out of the system, which will make it extremely difficult for bad actors to attack the network by compromising nodes.