Front-running awareness in Blockchain / Solidity - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is front-running in blockchain transactions?

Front-running is when someone sees a pending transaction and tries to get their own transaction processed first to benefit from the information, often by paying higher fees.

beginner

How does front-running affect decentralized exchanges (DEXs)?

Front-running can cause users to get worse prices because attackers place orders before them, exploiting the time delay in transaction processing.

intermediate

What is a common method to reduce front-running risk on blockchain?

Using techniques like transaction ordering protocols, commit-reveal schemes, or private transaction pools to hide transaction details until confirmed.

intermediate

Explain the role of gas fees in front-running.

Attackers pay higher gas fees to get miners to prioritize their transactions, allowing them to jump ahead of others in the transaction queue.

advanced

What is MEV (Miner Extractable Value) and how is it related to front-running?

MEV is the profit miners can make by reordering, including, or excluding transactions in a block, often exploiting front-running opportunities.

What does front-running in blockchain usually involve?

A Paying higher fees to get a transaction processed first

B Submitting a transaction before seeing others

C Copying a transaction after it is confirmed

D Ignoring transaction fees

Front-running involves paying higher fees to get a transaction processed before others.

Which of these helps reduce front-running risk?

A Increasing transaction size

B Broadcasting transactions publicly early

C Using low gas fees

D Commit-reveal schemes

Commit-reveal schemes hide transaction details until confirmation, reducing front-running.

What role do miners play in front-running?

A They ignore transaction order

B They only process transactions with zero fees

C They can reorder transactions for profit

D They prevent front-running automatically

Miners can reorder transactions to maximize their profit, enabling front-running.

What is MEV in blockchain?

A Miner Extractable Value

B Maximum Ethereum Value

C Minimum Exchange Volume

D Multi-Exchange Verification

MEV stands for Miner Extractable Value, related to profits from transaction ordering.

Why do attackers pay higher gas fees in front-running?

A To slow down their transactions

B To get their transactions processed faster

C To reduce transaction size

D To avoid transaction confirmation

Higher gas fees incentivize miners to process transactions faster, helping attackers front-run.

Describe what front-running is and why it is a problem in blockchain.

Think about how someone might try to get ahead in the transaction queue.

Explain at least two methods used to reduce front-running risks in blockchain systems.

Consider how hiding or delaying transaction details can help.