Using an Ethereum RPC endpoint
You spend hours researching coins, perfecting your entry and exit points, and strategizing every move. You're strategic when it comes to your transactions-so why wouldn't you be just as strategic about the infrastructure that makes those transactions possible?
The truth is, while every endpoint will connect you to the network, not every endpoint is set up for real financial success.
In this post, we're going to dive into how traders use protected RPC endpoints for more secure transactions and ultimately, more profitable trades - and how CoW DAO can help keep you protected.
Endpoints are for Connection, Not Built-in Protection
When you connect your wallet to a DeFi app (like a DEX or CoW Swap), you're using an RPC endpoint to talk to the blockchain. Think of it as the API that links your crypto life to an Ethereum node.
This connection is what allows you to:
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Query blockchain data (check balances, gas prices)
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Send transactions (swaps, transfers)
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Interact with smart contracts
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Monitor network events
An easy analogy? Your smartphone is useless without a data network. Similarly, your crypto wallet isn't much use without an RPC endpoint.
But just like there are countless data networks for your phone-some more secure and reliable than others-the same holds true for RPC endpoints.
The Security Difference: Public vs. Private RPCs
The most common endpoints are public RPCs. They're free and functional, but they often get congested. More importantly for traders, their default public mempool routing makes your transactions a sitting duck for front-running bots.
Enter private endpoints.
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They reduce your MEV (Maximal Extractable Value) risk by routing your transaction away from the public eye.
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By reducing visibility, they significantly reduce your exposure to malicious searchers.
A standard private endpoint is a huge step up, but it won't completely eliminate the MEV risk. That's why specialized RPCs-often called MEV Blockers - have emerged. These dedicated services work with a permissionless network of searchers who are explicitly prevented from frontrunning your transactions. That's real protection!
How Traders Use Protected RPC Endpoints in Practice
How do these protective RPCs work on a day-to-day basis? Here are a few practical scenarios where they can save you time and money.
Swapping Tokens for Better Prices
When you initiate a swap, a protected RPC endpoint routes your transaction through a private channel instead of the public mempool, shielding it from visibility until it's actually included in a block.
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The Help: Because your transaction is hidden, bots can't spot your trade, frontrun it, or sandwich it for a profit. This means your swap is far more likely to execute closer to the quoted market price.
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Example: A trader swaps 1 ETH for USDC. By sending a transaction through a protected RPC, it's safe from mempool bots and executes at a much better rate than if it were publicly broadcast.
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Action: Simply configure your wallet (like MetaMask) or dApp to use the MEV-protected RPC endpoint and swap as usual.
Providing Liquidity with Minimized LVR
Loss Versus Rebalancing (LVR) is the value leak that liquidity providers (LPs) experience when arbitrageurs rebalance pools after market shifts. It's essentially a slow drain on your profits.
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The Help: Protected RPCs reduce this exposure by preventing bots from anticipating or reacting to your liquidity operations (adding or removing tokens) before they are finalized on the chain.
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Example: An LP adds tokens to a pool through a protected RPC (like CoW AMM). Since the transaction isn't visible in the public mempool, arbitrage bots can't adjust prices ahead of inclusion, preserving more value for the LP.
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Action: Connect to the protected RPC and add/remove liquidity as you normally would. Pro-Tip: Before providing liquidity, confirm your chosen RPC supports private relay for smart contract interactions, not just token swaps! In other words, choose CoW AMM if you want the simplest most effective solution to preventing LVR.
Automating Strategies (TWAP, Conditional Orders)
Automated strategies like Time-Weighted Average Price (TWAP) rely on predictable execution over a period of time. If these transactions are visible in advance, other participants can easily exploit that predictability.
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The Help: Routing through a private RPC prevents your sophisticated strategies from being copied or countered mid-execution, ensuring your automation works as intended.
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Example: A trading script executes incremental swaps every 10 minutes. Using a protected RPC ensures each transaction is hidden until confirmed, preventing others from "gaming the schedule" and ruining your average price.
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Action: Configure your bot or smart contract to send transactions via a protected RPC provider. Always test your integration on a testnet first!
Setting Up an Ethereum RPC with MEV Protection
Ready to set up your shield? It's often as straightforward as changing the DNS settings on your computer.
Let's use MEV Blocker as an example, as it's a popular, specialized RPC designed for this purpose (and we love it too):
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Visit the MEV Blocker website.
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Select your network (Ethereum Mainnet).
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Choose your wallet (MetaMask, WalletConnect, etc.).
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Follow the instructions to add the custom RPC network to your wallet.
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Verify the connection in your wallet's network settings.
Example: Setting Up with MetaMask
For a one-time setup that provides ongoing protection, here's what your configuration would look like:
Setting - Value
Network Name - MEV Blocker Mainnet
RPC URL - https://rpc.mevblocker.io
Chain ID - 1
Currency Symbol - ETH
Best Practices for Using a Protected RPC Endpoint
You're set up! To make sure you're getting the most out of your new shield, keep these tips in mind:
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Verify Your Configuration: Double-check that the RPC URL, chain ID, and network name match official sources before sending any transaction.
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Maintain Fallback Endpoints: Keep a secondary RPC (even a public one) handy in case your primary protected one experiences downtime or congestion.
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Test Before Going Live: Run a small transaction on a testnet or sandbox to confirm correct signing and inclusion behavior before trading real value.
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Protect Your Keys: RPC privacy is not a substitute for key security! Always use hardware wallets or secure signers.
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Know the Limits: While an RPC is a great start, no endpoint can guarantee the absolute best trade all by itself. For the ultimate performance, combine your endpoint with protocols designed for batch settlement or solver-based execution (like CoW Protocol) which can further enhance your protection and price.
Your Choice of RPC Endpoint Matters
It's clear that your choice of RPC endpoint is a critical decision - it directly affects how securely and efficiently your transactions reach the blockchain.
Protected RPCs are the new standard, addressing MEV by routing transactions privately and reducing information leaks to help ensure fairer execution.
For CoW Swap traders, this protection extends even further: MEV Blocker routes transactions through a permissionless network of solvers who compete to include them without frontrunning. This, combined with CoW Protocol's batch settlement system, creates a powerful, multi-layered defense against MEV extraction.
By understanding how RPCs work and taking the simple step of configuring your wallet to use MEV protection, you're not just improving your own execution and saving money - you're contributing to a healthier, fairer Ethereum ecosystem for everyone.
Read More
Want to dive deeper into private RPCs? Check out the content below:
👉 Try CoW MEV Blocker — use a private, MEV-protected RPC to keep your Ethereum transactions safe from searchers.
FAQs for using Ethereum RPC endpoints
What is an Ethereum RPC endpoint?
An Ethereum RPC endpoint is an interface that connects your wallet or application to an Ethereum node. It allows you to query blockchain data, send transactions, and interact with smart contracts. In practice, it’s the communication channel between your wallet and the blockchain network — similar to how your phone connects to the internet through a mobile carrier.
How does an RPC endpoint affect my Ethereum transactions?
The RPC endpoint you use determines how and where your transactions are broadcast before they’re included in a block. Public endpoints broadcast transactions to the open mempool, where they’re visible to everyone, including bots. Private or MEV-protected RPCs route transactions through closed relays, reducing exposure to frontrunning and other manipulative behaviors.
What is MEV, and how does it affect my Ethereum trades?
MEV (Maximal Extractable Value) refers to the profit miners or searchers can extract by reordering or inserting transactions within a block. It can result in worse execution prices, failed trades, or higher gas costs for regular users. Understanding and mitigating MEV is essential for maintaining fair and predictable transaction outcomes on Ethereum.
What are the risks of using a public RPC endpoint?
Transactions sent through public RPC endpoints are visible in the public mempool, allowing bots to frontrun, sandwich, or copy your trades. This can lead to slippage, higher gas costs, and even lost value during periods of high volatility. Using a protected RPC helps shield your transactions from this kind of real-time manipulation.
Can using a private RPC completely eliminate MEV?
No, private RPCs significantly reduce but do not entirely eliminate MEV risk. They protect against frontrunning and sandwich attacks but can’t prevent all forms of value extraction that occur during block construction. Combining protected endpoints with systems like batch auctions or solver-based execution adds another layer of defense.
How do protected RPCs help liquidity providers?
When liquidity providers add or remove liquidity, their transactions can reveal market-moving information. Protected RPCs prevent this visibility, reducing small but cumulative “loss versus rebalancing” (LVR) events caused by arbitrage bots. This results in fairer and more stable returns for long-term LPs.
How can I set up a protected RPC like MEV Blocker?
To set up MEV Blocker, visit cow.fi/mev-blocker and follow the on-screen instructions for your wallet, such as MetaMask or WalletConnect. You’ll add a custom RPC configuration that replaces the default public endpoint with a private one. Once connected, your transactions will route through a MEV-resistant relay by default.
