CBDH Online Practice Questions and Answers

Correct Answer: D

Correct Answer: A

Correct Answer: D

Correct Answer: D

Correct Answer: A

Correct Answer: C

Correct Answer: B

Consensus is when the distributed ledger has been updated and all nodes maintain their own identical copy of the ledger. This is also known as the "World State" in some blockchains. This architecture allows for a new capacity as a system of recordkeeping that goes beyond being a simple database.

Correct Answer: D

Correct Answer: B

Hyperledger is a private validator network protocol. All the entities in a network must register with membership services to obtain an identity with access and transaction authority on the network. Validators determine the level of permissions required to transact. The network setup also defines the network as permissive, allowing the ease of access. It supports for rapid and high adoption for a more controlled and restrictive environment.

Correct Answer: B

The security module works in conjunction with the membership service module to provide access control service to any data recorded and business logic deployed on a chain network.

Correct Answer: C

To create a network according to an organization's structure, and to bootstrap a channel, we will need to generate the following artifacts: A genesis block, containing organization-specific certificates that serve to initialize the Fabric blockchain. Channel configuration information. Anchor peer configurations for each organization. An anchor peer serves as a fulcrum within an organization, for cross-organization ledger syncing using the Fabric gossip protocol.

Correct Answer: E

Orderer Ordering services handles the main function of the Hyperledger Fabric to maintain consistency in the transactions processes. Ordering services provides a shared communication to clients and peers and helps in broadcasting the messages containing transactions.

Correct Answer: B

The ledger system in Hyperledger fabric uses levelDB. By definition, LevelDB allows concurrent writers to safely insert data into the database by providing internal synchronization. LevelDB uses very coarse-grained synchronization which forces all writes to proceed in an ordered, first-come-first- served basis, effectively reduces throughput to a single thread. State database options include LevelDB and CouchDB. LevelDB is the default key-value state database embedded in the peer process. CouchDB is an optional alternative external state database. Like the LevelDB key-value store, CouchDB can store any binary data that is modeled in chaincode (CouchDB attachment functionality is used internally for non- JSON binary data). But as a JSON document store, CouchDB additionally enables rich query against the chaincode data, when chaincode values (e.g. assets) are modeled as JSON data

Correct Answer: C

Correct Answer: D

Invoke is called to update or query the ledger in a proposal transaction. Init is called during Instantiate transaction after the chaincode container has been established for the first time, allowing the chaincode to initialize its internal data. Invoke is called to update or query the ledger in a proposal transaction. Updated state variables are not committed to the ledger until the transaction is committed.