Common use of Algorithm Clause in Contracts

Algorithm. Next, we present an algorithm that solves Byzantine agree- ment assuming ℓ > 3t. Our agreement algorithm is generic: given any synchronous Byzantine agreement algorithm for ℓ processes with unique identifiers (such algorithms exist when ℓ = n > 3t, e.g., [13]), we transform it into an algorithm for n processes and ℓ identifiers, where n ≥ ℓ. Without loss of generality, we assume that the algorithm to be transformed uses broadcasts: a process sends the same message to all other processes. (If a process wishes to send a message only to specific recipients, it could include the recipient’s identi- fier in the broadcasted message.) In our transformation, we divide processes into groups ac- cording to their identifiers. Each group simulates a single process. If all processes within a group are correct, then they can reach agreement and cooperatively simulate a sin- gle process. If any process in the group is Byzantine, we allow the simulated process of that group to behave in a Byzantine manner. The correctness of our simulation re- lies on the fact that more than two-thirds of the simulated processes will be correct (since ℓ > 3t), which is enough to achieve agreement.