How Blockchain APIs and RPC Nodes Work

Ironically, a lot of blockchain projects and developers still depend on centralized structures. This dependency is largely due to the challenges associated with building and maintaining blockchain applications (or dApps). To address these challenges, the foundation of dApps and other blockchain services relies on blockchain APIs and RPC nodes. By using these tools, developers can communicate with blockchain networks more efficiently, avoiding the costs and technical complexities of independently operating a full node.

In this article, I’ll explain blockchain APIs and RPC nodes, why they are important to the ecosystem, and how they connect complex blockchain data to user-friendly apps. I’ll also explore real-world examples comparing centralized systems like Infura with decentralized alternatives like dRPC or Pocket Network.

What Are Blockchain APIs?

Let's start by addressing the obvious: blockchain is not the only platform that uses APIs (application programming interfaces). They are used all across the internet to facilitate communication between various software programs. API communication can take the form of back-and-forth communication between two servers or OS system and application communication. Nearly every day, users communicate with APIs via email, social media, and other channels.

Depending on the use cases, APIs have a wide range of applications. Some firms, like Twilio, Sendbird, Stripe, PayStack, and Anchor, rely entirely on giving developers APIs to use in the creation of their products. Because of these services, the "API Economy" was established, enabling developers to quickly and simply incorporate the functionality these services provide into their businesses.

But in the context of blockchain, APIs serve a unique purpose—they make blockchain functionality more accessible to developers who don’t want to, or can't, deal with the nitty-gritty of running and managing a blockchain node.

Blockchain APIs essentially act as intermediaries between the blockchain network and your application, abstracting away the complexity of interacting with the blockchain directly. Think of it like using a remote control instead of getting up and fiddling with the TV’s settings directly. With APIs, developers can query blockchain data (like account balances or transaction histories), interact with smart contracts, or even broadcast transactions to the network, all without needing to host their own full node.

Centralized API Solutions: Infura and Alchemy

One of the most popular centralized blockchain API providers is Infura. It provides Ethereum developers with an easy way to interact with the Ethereum network through API endpoints. For instance, if you’re building a crypto wallet app, you don’t want to run your own Ethereum node just to check account balances. Instead, you can use Infura’s API to query the balance of an address in real time, without the headache of node management. This makes life easier for developers, but it comes with a downside—centralization.

Alchemy is another centralized solution that offers more than just API access. Alchemy helps developers build applications with tools to monitor blockchain data, trace transactions, and even query NFTs. If you’ve ever used an NFT marketplace, there’s a good chance that the backend relied on Alchemy’s API for data fetching and transaction management.

These centralized platforms provide reliability and ease of use, but as we’ll discuss, they come with some tricky trade-offs.

What Are RPC Nodes?

Now, let’s talk about RPC nodes (Remote Procedure Call nodes). At their core, RPC nodes serve as the gateway for developers to directly interact with the blockchain at a low level. When a dApp or wallet sends a request to an RPC node, it asks the node to fetch data from the blockchain or broadcast a transaction on its behalf.

Whereas APIs provide a simplified, high-level interaction with blockchain networks, RPC nodes offer raw access to blockchain functions. For example, you might use an RPC call to query the data in a specific block or to fetch information about a particular transaction hash.

If you’re running your own Ethereum node, you’d use Ethereum’s built-in RPC interface (like Geth or Parity) to interact directly with the blockchain. This means that you have full control over the node, but it also means you’re responsible for everything—from maintaining uptime to dealing with data storage.

Decentralized RPC Solutions: dRPC and Pocket Network

Decentralization purists often prefer to avoid centralized services like Infura. This is where decentralized RPC providers like dRPC and Pocket Network come into play. These platforms offer access to blockchain nodes that are run across a distributed network, helping to eliminate the risks associated with relying on a single service provider.

Take dRPC, for instance. It’s a decentralized platform where the infrastructure for accessing blockchain data is distributed across multiple participants. Rather than relying on a centralized service like Infura, developers using dRPC can access blockchain data from a wide network of nodes, making the system more resilient to outages and censorship.

Similarly, Pocket Network offers a decentralized infrastructure for dApp developers. When you use Pocket’s RPC services, your requests are handled by multiple nodes across the network, providing redundancy and eliminating central points of failure. This approach not only supports the decentralized ethos of blockchain but also enhances security and fault tolerance.

Why Blockchain APIs and RPC Nodes Matter

Now that we understand the difference between blockchain APIs and RPC nodes, let’s dive into why they matter. Whether centralized or decentralized, these tools are essential for building blockchain-based applications, whether it’s for decentralized finance (DeFi), NFTs, or simple wallet apps. Here’s a practical look at how they work in the real world.

Using Infura for Ethereum Wallets

Imagine you’re building an Ethereum wallet app. You need to show users their account balances and transaction history. Rather than running your own Ethereum node, which requires time, technical know-how, and a lot of bandwidth, you can simply use Infura’s API to make a request like `eth_getBalance`. Infura fetches the balance directly from the blockchain and sends it back to your app, which then displays it to the user.

Here’s how I used infra to generate account balances for my wallet app:

const Web3 = require('web3');
// Connect to Infura's Ethereum Mainnet node
const web3 = new Web3(new Web3.providers.HttpProvider('//mainnet.infura.io/v3/YOUR_INFURA_PROJECT_ID'));

async function getBalance(address) {const balance = await web3.eth.getBalance(address);
console.log("Balance in Wei: ", balance);
console.log("Balance in Ether: ", web3.utils.fromWei(balance, 'ether'));
}

// Replace with an Ethereum address
const address = '0x742d35Cc6634C0532925a3b844Bc454e4438f44e';
getBalance(address);

The beauty of using an API is that you can scale your application without worrying about the infrastructure. But there’s a catch: by using Infura, you’re relying on a single service provider, which introduces centralization risks. If Infura goes down, your wallet app could go down with it.

Decentralized RPC Access via dRPC

Now, let’s say you’re building the same wallet but want to stick to the core principle of decentralization. This is where you’d turn to something like dRPC. Instead of sending your blockchain queries to a centralized service, dRPC distributes the load across multiple independent nodes. If one node goes offline, others can step in to handle the requests, ensuring uptime and reliability.

For example, you could send a request to query Ethereum transaction data or to broadcast a user’s signed transaction. Instead of relying on Infura or Alchemy, dRPC would route that request through its decentralized node infrastructure. This not only decentralizes access but also makes the app more resilient against potential outages or attacks on centralized services.

My code:

const Web3 = require('web3');

// Replace with your dRPC provider URL
const DRPC_PROVIDER = '//your-drpc-endpoint-url';
const web3 = new Web3(DRPC_PROVIDER);

// Example signed transaction data (this should be generated by signing a transaction with the user's private key)
const signedTransaction = '0xf86c808504a817c80082520894f03d67f07fbd17c1afc38e58ca7d68219b7c991187038d7ea4c68000802ca05d1b2a8592496374e6c8f68cf8d0b175de695e36dba7696f89b687ab75810772a04299dd5a54dff4fef7989dc99e63a5e3b178418c58b89ef83f7e11522939b94';
// Function to broadcast the signed transaction using dRPC
async function broadcastTransaction() {try {const receipt = await web3.eth.sendSignedTransaction(signedTransaction);
console.log('Transaction broadcasted successfully:', receipt);
} catch (error) {console.error('Error broadcasting transaction:', error);
}
}
broadcastTransaction();

Code Explanation

The code connects to dRPC through the decentralized RPC provider URL (DRPC_PROVIDER), ensuring that your app is leveraging decentralized infrastructure.

Before this script, your users would sign the transaction using their private key. In this example, signedTransaction is a placeholder for the actual signed transaction.

The script uses web3.eth.sendSignedTransaction to broadcast the signed transaction to the Ethereum network via dRPC. This request will be routed through multiple independent nodes, providing resilience in case one node goes offline.

Centralized vs Decentralized Solutions: The Trade-Off

So which one should you use? centralized APIs or decentralized RPC solutions? The answer depends on your priorities.

• Centralized solutions like Infura and Alchemy offer ease of use, reliability, and scalability. They abstract away the technical headaches of running your node, allowing developers to focus on building their applications. However, the reliance on a single provider goes against the decentralized ethos of blockchain and introduces risks of downtime or censorship.

• Decentralized solutions like dRPC and Pocket Network are more aligned with blockchain’s decentralized ideals. They offer resilience and redundancy by distributing requests across multiple nodes. However, decentralized networks can be slower or harder to set up, and they often don’t come with the same level of customer support or simplicity as their centralized counterparts.

Conclusion: Building in the Blockchain Ecosystem

Blockchain APIs and RPC nodes play an essential role in the blockchain ecosystem. They make blockchain data accessible and usable, whether you’re querying account balances, fetching transaction histories, or interacting with smart contracts. Whether you choose a centralized or decentralized system, you are working with an innovative concept that is transforming the way we look at Web3