RPC Node

An RPC (Remote Procedure Call) node is a blockchain node that exposes an API interface allowing external applications to interact with the blockchain without running their own node infrastructure. RPC nodes serve as the critical bridge between user-facing applications (wallets, dApps, block explorers) and the underlying blockchain network, handling requests to read blockchain state, submit transactions, estimate gas costs, and more.

Most blockchain users interact with RPC nodes daily without realizing it—every time you check your wallet balance, swap tokens on a DEX, or mint an NFT, your application is making RPC calls to a node provider like Infura, Alchemy, QuickNode, or a public endpoint.

RPC nodes are essential infrastructure for the decentralized web, but they also represent a potential centralization point, as many applications rely on a small number of commercial RPC providers rather than running their own nodes.

How RPC Nodes Work

An RPC node runs the full blockchain client software (like Geth for Ethereum, Solana's validator client, etc.) and exposes an HTTP or WebSocket API that accepts standardized JSON-RPC requests. Here's the typical flow:

1. Application Request: A dApp or wallet makes an RPC call (e.g., eth_getBalance to check an account's ETH balance)
2. RPC Endpoint: The request is sent to an RPC endpoint URL (e.g., https://eth-mainnet.g.alchemy.com/v2/YOUR-API-KEY)
3. Node Processing: The RPC node receives the request, queries its local blockchain database, and processes the request
4. Response: The node returns the requested data (account balance, transaction receipt, block data, etc.) to the application
5. Application Display: The app displays the result to the user (e.g., "Your balance: 2.5 ETH")

RPC nodes handle millions of requests daily, with response times typically ranging from 100-500ms depending on the query complexity and provider infrastructure.

Common RPC Methods

Different blockchains expose different RPC methods, but Ethereum's JSON-RPC specification is widely adopted. Common methods include:

Reading Blockchain State:

• eth_blockNumber: Get the latest block number
• eth_getBalance: Get an account's ETH balance
• eth_getTransactionByHash: Retrieve transaction details
• eth_call: Execute a smart contract function without submitting a transaction (read-only)
• eth_getLogs: Query event logs from smart contracts

Sending Transactions:

• eth_sendRawTransaction: Submit a signed transaction to the network
• eth_estimateGas: Estimate the gas required for a transaction
• eth_gasPrice: Get the current recommended gas price

Network Information:

• eth_chainId: Get the chain ID (1 for Ethereum mainnet, 137 for Polygon, etc.)
• net_version: Get the network ID
• web3_clientVersion: Get information about the node client

These methods form the foundation of blockchain application development, enabling developers to build complex applications without understanding the low-level protocol details.

Types of RPC Nodes

RPC infrastructure comes in several forms:

Full Nodes: Store the complete blockchain history and can answer any query about any block or transaction. Require significant storage (multiple terabytes for Ethereum) but provide complete data access.

Archive Nodes: Like full nodes but also store historical state at every block, enabling queries like "what was this address's balance at block 10,000,000?" Archive nodes require even more storage (10+ TB for Ethereum).

Light Clients: Store only block headers and request data from full nodes as needed. Much lower resource requirements but rely on full nodes for data.

Pruned Nodes: Store only recent state (e.g., last 128 blocks) and discard old historical data to reduce storage requirements while still syncing new blocks.

Most commercial RPC providers run archive nodes to support the widest range of queries, while individual users typically run full or pruned nodes.

Commercial RPC Providers

Several companies offer RPC infrastructure as a service:

Infura: One of the earliest and most popular Ethereum RPC providers, offering free tier (up to 100,000 requests/day) and paid plans. Supports Ethereum, Polygon, Arbitrum, Optimism, and other EVM chains.

Alchemy: Comprehensive blockchain development platform with RPC endpoints, enhanced APIs, and developer tools. Known for high reliability and performance. Offers generous free tier.

QuickNode: Multi-chain RPC provider with global infrastructure and add-ons for analytics, webhooks, and specialized APIs. Subscription-based pricing.

Ankr: Decentralized RPC network with public free endpoints and premium paid options. Supports 50+ blockchain networks.

Chainstack: Enterprise-focused node infrastructure with managed nodes, elastic scaling, and compliance features.

Public Endpoints: Many chains operate free public RPC endpoints (e.g., Cloudflare's https://cloudflare-eth.com), though these often have rate limits and lower reliability.

As of 2026, Alchemy and Infura together handle an estimated 60%+ of Ethereum mainnet RPC traffic, raising decentralization concerns.

Why Applications Use RPC Providers

Running your own blockchain node requires significant resources:

Infrastructure Costs: Dedicated servers, fast SSDs (1-4 TB), high bandwidth (2+ TB/month), and reliable uptime—easily $100-500+/month per node.

Technical Complexity: Node setup, synchronization, monitoring, security, and maintenance require DevOps expertise and ongoing attention.

Sync Time: Initial synchronization can take days to weeks depending on the blockchain and node type.

Reliability: Ensuring 99.9%+ uptime requires redundancy, monitoring, and rapid incident response.

Multi-Chain Support: Supporting multiple blockchains multiplies the cost and complexity.

Commercial RPC providers amortize these costs across thousands of customers, offering professionally-managed infrastructure at lower effective cost than self-hosting for most developers, especially during early product development.

RPC Centralization Concerns

Heavy reliance on commercial RPC providers creates several risks:

Censorship: RPC providers could filter transactions from sanctioned addresses (as some have done to comply with OFAC regulations), preventing users from interacting with the blockchain.

Single Point of Failure: If a major provider like Infura has an outage, hundreds of dApps can go down simultaneously, as happened during major Infura outages in 2020 and 2022.

Data Manipulation: A malicious RPC provider could return false data (wrong balances, fake transaction confirmations), though this is detectable if users verify on-chain.

Privacy Leakage: RPC providers see all requests, potentially linking addresses to IP addresses and revealing trading strategies or other sensitive information.

Vendor Lock-In: Applications tightly integrated with provider-specific APIs face switching costs if they want to change providers or self-host.

The blockchain community has increasingly recognized RPC centralization as a critical threat to decentralization, spurring efforts to develop alternative models.

Decentralized RPC Solutions

Several projects are building decentralized alternatives to centralized RPC providers:

Pocket Network: Decentralized RPC network where node operators are incentivized with POKT tokens to provide RPC services. Claims 40,000+ nodes globally.

Ankr Premium: Hybrid model combining decentralized node network with professional infrastructure for enterprise reliability.

DRPC: Decentralized RPC marketplace where users can discover and use community-operated nodes.

Lava Network: Modular blockchain for decentralized RPC and API access, with quality-of-service guarantees and permissionless participation.

dRPC: Protocol for routing RPC requests across multiple providers with automatic failover and load balancing.

These solutions aim to provide the reliability of commercial providers with the censorship resistance and decentralization of running your own node.

Running Your Own RPC Node

For projects prioritizing decentralization or needing specialized access, running your own node remains an option:

Hardware Requirements (Ethereum full node):

• CPU: 4+ cores
• RAM: 16+ GB
• Storage: 2-4 TB fast SSD
• Network: Unlimited bandwidth, 10+ Mbps

Software Options:

• Geth (Go Ethereum): Most popular Ethereum client
• Erigon: High-performance Ethereum client with lower storage requirements
• Nethermind: .NET-based Ethereum client with archive node support
• Besu: Java-based Ethereum client with enterprise features

Deployment Options:

• Bare metal server (highest performance)
• Cloud VPS (AWS, DigitalOcean, Hetzner)
• Docker containers (simplified deployment)
• Kubernetes (enterprise-scale orchestration)

Initial sync can take 24-72 hours for a full node, or 1-2 weeks for an archive node. Ongoing maintenance requires monitoring disk usage, software updates, and network connectivity.

RPC Node Security

RPC nodes require careful security configuration:

Access Control: Restrict access to authorized IPs or use API keys to prevent abuse and unauthorized access.

Rate Limiting: Implement request throttling to prevent DoS attacks and manage resource usage.

HTTPS/TLS: Always use encrypted connections to prevent man-in-the-middle attacks and protect sensitive data.

Firewall Rules: Block unnecessary ports and only expose RPC endpoints to necessary networks.

DDoS Protection: Use services like Cloudflare or AWS Shield to absorb volumetric attacks.

Request Validation: Sanitize inputs and validate requests to prevent malicious queries from crashing the node or leaking information.

Monitoring: Track request volumes, error rates, and resource usage to detect anomalies and potential attacks.

Misconfigured RPC nodes have been exploited to drain resources, extract sensitive data, or serve as attack vectors against other infrastructure.

Career Opportunities in RPC Infrastructure

The RPC infrastructure ecosystem creates several specialized roles:

Blockchain Infrastructure Engineers ($150,000 - $350,000+): Build, deploy, and maintain RPC node infrastructure at scale, optimizing for performance, reliability, and cost.

DevOps Engineers (Blockchain Focus) ($140,000 - $320,000+): Manage node deployments, monitoring, alerting, and automation across multiple blockchain networks.

Protocol Engineers ($170,000 - $360,000+): Develop RPC client software, implement new JSON-RPC methods, and optimize node performance.

Site Reliability Engineers (SRE) ($160,000 - $340,000+): Ensure 99.99%+ uptime for RPC services, implement disaster recovery, and manage incident response.

Network Engineers ($130,000 - $280,000+): Design and optimize network architecture for global RPC infrastructure, minimizing latency and maximizing throughput.

RPC infrastructure work requires expertise in distributed systems, networking, blockchain protocols, and large-scale operations.

Best Practices for Using RPC Nodes

When building applications that rely on RPC nodes:

Use Multiple Providers: Implement fallback logic to switch between multiple RPC providers if one fails, improving reliability.

Cache Responses: Cache blockchain data that doesn't change (historical transactions, block data) to reduce RPC requests and improve performance.

Optimize Queries: Use batch requests to fetch multiple pieces of data in one RPC call, reducing latency and request counts.

Monitor Usage: Track your RPC usage to stay within free tier limits or optimize costs on paid plans.

Respect Rate Limits: Implement exponential backoff and retry logic when rate limited.

Use WebSockets for Events: For real-time data (new blocks, pending transactions), use WebSocket subscriptions rather than polling.

Verify Critical Data: For high-value operations, verify critical data (like token balances before transfers) against multiple independent sources.

Consider Self-Hosting: For production applications with significant usage, evaluate the cost-benefit of running your own nodes.

The Future of RPC Infrastructure

RPC infrastructure continues to evolve:

Decentralized Networks: Growth of decentralized RPC networks like Pocket and Lava, reducing reliance on centralized providers.

Light Client Renaissance: Advances in light client technology (Portal Network, Helios) enabling users to run low-resource clients that verify data trustlessly.

RPC as a Protocol Layer: Integration of RPC functionality into protocol design (e.g., Ethereum's Portal Network making RPC data available peer-to-peer).

Privacy-Preserving RPC: Mixnets, VPNs, and encrypted request routing to prevent RPC providers from tracking user activity.

Cross-Chain RPC Aggregation: Unified interfaces that route requests to the appropriate blockchain, simplifying multi-chain development.

The infrastructure layer will likely become more decentralized, performant, and privacy-preserving, reducing the centralization risks that exist today.

Building blockchain applications? Start with a reliable RPC provider like Alchemy or Infura, implement proper error handling and caching, and plan a path toward decentralization as your application scales.