Blockchain CBDH Practice Test - Questions Answers, Page 3

Hyperledger Fabric includes the REST and JSON RPC APIs, events, and an SDK for applications to communicate with the network.

Channels ensure privacy in a blockchain network Ordering services may support many channels no just one channel.

While smart contracts (Chaincode) can be written to complement or substitute for legal contracts, their legal enforceability is not yet agreed upon by all state governments

Endorsing Peer can be marked as Endorser peer (i.e. Endorsing peer). Upon receiving the “transaction invocation request” from the Client application the Endorser peer Validates the transaction. Check certificate details and roles of the requester. Executes the Chaincode (Smart Contract) and simulates the outcome of the transaction. But it does not update the ledger. At the end of the above two tasks the Endorser may approve to disapprove the transaction. As only the Endorser node executes the Chaincode (Smart Contract) so there is no necessity to install Chaincode in each and every node of the network which increases the scalability of the network.

X509 certificates are used in Hyperledger Fabric. An X.509 certificate is any certificate under the X.509 specification standard for public key infrastructure and Privilege Management Infrastructure (PMI). The X.509 provides standardized formats for: Attribute certificates Public key certificates Certificate revocation lists Certification validation algorithms

Consensus is when the distributed ledger has been updated and all nodes maintain their own identical copy of the ledger which essentially is an agreement. 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.

Peer-to-Peer essentially uses data sharing, hosting hardware owned by many not few, fault tolerant, secure, lower performance. It’s common way to share files—a good example was Napster. Peer-to-peer (P2P) file sharing is the distribution of digital media such as software, videos, music, and images through an informal network in order to upload and download files. Typically, P2P software enables users to select which files to share. These files are indexed on a central server, making them available for other users to find and download.

Code invoking transaction is an REST API call to a chaincode function and is similar to how a URL pattern invokes a servlet in J2EE. ServletServlet can be used to create a default mapping for servlets. For example, to create a default mapping to map all servlets to /myservlet/*, so the servlets can be called using http://host:port/web-app-name/myservlet/com/foo/FooServlet, add the following to your web.xml file. (The web.xml file is located in the WEB-INF directory of your Web application.) ServletServlet weblogic.servlet.ServletServlet ServletServlet /myservlet/*

Composer (contributed by IBM and Oxchains) is a set of collaboration tools for building blockchain business networks that accelerate the development of smart contracts and blockchain applications, as well as their deployment across a distributed ledger.