CBSA Solution Deployment & Integration 4 — Questions and Answers
Question 1: A blockchain architect is evaluating container orchestration for a Fabric deployment. Which Kubernetes feature is most important for maintaining peer node identity across pod restarts?
- Horizontal Pod Autoscaler
- StatefulSets with persistent volume claims (Correct answer)
- Ingress controllers
- ConfigMaps for environment variables
Correct answer: StatefulSets with persistent volume claims
StatefulSets provide stable network identities and persistent storage, ensuring peer nodes retain their cryptographic material and ledger data across pod restarts.
Question 2: During blockchain network deployment, which TLS configuration is recommended for peer-to-peer communication in Hyperledger Fabric?
- Disable TLS for performance optimization in private networks
- Enable mutual TLS (mTLS) so both client and server authenticate each other (Correct answer)
- Use self-signed certificates managed by each organization independently
- Configure TLS only for external client connections, not inter-peer traffic
Correct answer: Enable mutual TLS (mTLS) so both client and server authenticate each other
Mutual TLS ensures both communicating parties authenticate each other, preventing man-in-the-middle attacks even within a private network.
Question 3: A blockchain solution must integrate with an external payment processor. Which integration pattern best handles the asynchronous nature of blockchain finality?
- Synchronous REST call that waits for block finality before returning
- Saga pattern with compensating transactions to handle payment and blockchain confirmation independently (Correct answer)
- Direct database write to the payment processor's database
- Single atomic transaction spanning both systems
Correct answer: Saga pattern with compensating transactions to handle payment and blockchain confirmation independently
The Saga pattern manages distributed transactions by coordinating steps with compensating actions if any step fails, handling the inherent asynchrony of blockchain finality.
Question 4: When deploying an Ethereum-based DApp, what is the purpose of using Infura or Alchemy as part of the architecture?
- They provide smart contract auditing services
- They offer managed Ethereum node endpoints, eliminating the need to run and maintain full nodes (Correct answer)
- They replace MetaMask for user wallet management
- They provide decentralized storage for contract bytecode
Correct answer: They offer managed Ethereum node endpoints, eliminating the need to run and maintain full nodes
Infura and Alchemy provide hosted Ethereum node infrastructure via APIs, allowing DApp deployments to interact with the network without operating their own full nodes.
Question 5: A blockchain network experiences high transaction latency during peak load. Which architectural change most directly addresses throughput bottlenecks in Hyperledger Fabric?
- Increasing the number of orderer nodes in a Raft cluster
- Tuning block cutting parameters (BatchSize and BatchTimeout) to optimize block formation (Correct answer)
- Adding more Certificate Authorities to the network
- Enabling gossip data dissemination protocol for the first time
Correct answer: Tuning block cutting parameters (BatchSize and BatchTimeout) to optimize block formation
Tuning BatchSize and BatchTimeout controls how quickly blocks are cut, directly affecting throughput and latency tradeoffs in the ordering service.
Question 6: Which deployment model is most appropriate for a consortium blockchain where multiple competing companies must each independently verify transactions without trusting a central operator?
- Single-company hosted cloud deployment shared by all members
- Decentralized deployment where each organization operates its own peer nodes (Correct answer)
- Public blockchain where anyone can join as a validator
- Centralized ledger managed by a trusted third-party auditor
Correct answer: Decentralized deployment where each organization operates its own peer nodes
Each organization operating its own peer nodes ensures no single party controls validation, aligning with the trust model of a competitive consortium.
Question 7: A smart contract on Ethereum needs to call an external HTTP API to fetch real-world price data. Why can't it do this natively, and what is the solution?
- Ethereum nodes lack internet connectivity, solved by upgrading to Ethereum 2.0
- Smart contracts cannot make external calls because it would break determinism; decentralized oracle networks like Chainlink provide the solution (Correct answer)
- HTTP calls are blocked by Solidity's type system; the solution is to use Vyper instead
- External calls are possible but prohibited by the EVM gas limit
Correct answer: Smart contracts cannot make external calls because it would break determinism; decentralized oracle networks like Chainlink provide the solution
EVM execution must be deterministic across all nodes; non-deterministic HTTP calls would cause consensus failures, so oracle networks fetch and attest to external data before providing it on-chain.
CBSA Solution Deployment & Integration 4
A blockchain architect is evaluating container orchestration for a Fabric deployment.
Which Kubernetes feature is most important for maintaining peer node identity across pod restarts?