Problem 1: Consider the Merkle Damgard Transform. Explain how the mechanism is able to produce a fixed-length hash (say 256 bits) from an input of any length. What could be a potential shortcoming of this method, if any?
Problem 2: Explain how Hyperledger Fabric's architecture makes the ordering service modular, thus enabling it to choose from an "ecosystem of consensus protocols" for implementing the ordering service as per the application's need, instead of a single consensus protocol.