CBSA - Certified Blockchain Solution Architect Smart Contract Design Questions and Answers

Question 1

A development team is building a decentralized application (dApp) that will require periodic updates to its business logic after deployment.
Which smart contract design pattern is most appropriate to allow for these updates without requiring users to migrate to a new contract address?

Accepted Answer

The Proxy Pattern

Answer

The Singleton Pattern

Answer

The Factory Pattern

Answer

The Observer Pattern

Question 2

As a Blockchain Solution Architect, you are reviewing a smart contract designed for a decentralized finance (DeFi) lending protocol. You identify a function that sends funds to an external address before updating the internal state of the contract. Which of the following vulnerabilities is this design susceptible to?

Accepted Answer

Reentrancy Attack

Answer

Integer Overflow

Answer

Denial of Service (DoS)

Answer

Timestamp Dependence

Question 3

Which of the following is a primary benefit of designing smart contracts with a modular approach, breaking down complex logic into smaller, interconnected contracts or libraries?

Accepted Answer

It enhances code reusability, maintainability, and security.

Answer

It guarantees absolute immutability of the entire application.

Answer

It significantly reduces gas costs for all transactions.

Answer

It eliminates the need for any access control mechanisms.

Question 4

A team is designing a smart contract system where different user roles (e.g., admin, user, auditor) must have different permissions to execute certain functions. Which design pattern is most critical to implement for this requirement?

Accepted Answer

Access Control Pattern

Answer

State Machine Pattern

Answer

Pull-over-Push Pattern

Answer

Circuit Breaker Pattern

Question 5

In the context of smart contract design, what is the primary purpose of the 'Checks-Effects-Interactions' pattern?

Accepted Answer

To prevent reentrancy attacks by performing state changes before external calls.

Answer

To optimize gas consumption by batching multiple external calls.

Answer

To ensure that all function inputs are validated before execution.

Answer

To separate data storage from business logic for upgradeability.

Question 6

A Blockchain Solution Architect is designing a system that must be upgradable. They are considering the Diamond Pattern (EIP-2535). What is the main advantage of the Diamond Pattern over a standard Transparent Proxy Pattern?

Accepted Answer

It allows a single proxy contract to use logic from multiple implementation contracts (facets).

Answer

It offers a simpler implementation with less code.

Answer

It completely eliminates gas costs associated with `delegatecall`.

Answer

It enforces strict immutability, preventing any future upgrades.

A development team is building a decentralized application (dApp) that will require periodic updates to its business logic after deployment.Which smart contract design pattern is most appropriate to allow for these updates without requiring users to migrate to a new contract address?

A development team is building a decentralized application (dApp) that will require periodic updates to its business logic after deployment.
Which smart contract design pattern is most appropriate to allow for these updates without requiring users to migrate to a new contract address?