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Every crypto app, from wallets to exchanges, explorers, and DeFi protocols, constantly communicates with blockchains. Whether it’s checking a wallet balance, tracking on-chain activity, or submitting transactions.
This communication happens through blockchain nodes. A node maintains a copy of the blockchain, validates transactions, and serves as the gateway between an application and the blockchain network.
Running blockchain nodes is complex, resource-intensive, and often impractical for new projects and startups. Instead, most projects rely on blockchain node providers. These providers manage fleets of nodes and expose them through RPC endpoints, allowing developers to connect their applications to blockchains without managing the underlying infrastructure.
While this approach makes building crypto and Web3 applications faster and more scalable, it also introduces a critical dependency.
In this guide, we’ll explain how Web3 applications access blockchains, the role blockchain node providers play, and highlight the security considerations that come with relying on third-party providers.
What are Blockchain Nodes?
At its simplest, a blockchain node is a computer running blockchain software that stores and maintains a copy of a blockchain. It validates transactions and blocks according to the network’s consensus rules, keeps its copy of the ledger up to date, and shares information with other nodes on the network.
Source: Getblock
The major blockchain networks are made up of thousands of these nodes distributed around the world. Rather than relying on a central server, each node independently verifies transactions and blocks. This decentralized design ensures the network remains secure.
Not every node performs the same role. Some participate in producing new blocks, while others focus on validating transactions, storing blockchain data, and serving information to wallets, dApps, exchanges, and other applications.
Types of Blockchain Node
Full Nodes
A full node stores a complete copy of the blockchain and independently verifies transactions and blocks according to the network’s rules. They reject invalid data and share verified information with other nodes.
Some full nodes may prune older data to reduce storage requirements while keeping enough information to remain synchronized with the network.
Archive Nodes
Archive nodes are full nodes that store the complete historical state of a blockchain from the genesis block onward. Because they retain this additional data, they require significantly more storage than standard full nodes.
Archive nodes allow applications to query blockchain data exactly as it existed at any point in time, making them essential for block explorers, analytics platforms, and applications that rely on historical on-chain data.
Light Nodes
Light nodes are designed for efficiency. Instead of storing the entire blockchain, they store only essential information such as block headers and request additional data from full nodes when needed, making them ideal for lightweight applications such as mobile wallets.
Validator Nodes
Validator nodes are full nodes that participate in blockchain consensus and help produce new blocks. In Proof-of-Stake networks, validators stake tokens to propose and confirm blocks, while Proof-of-Work networks use miners to perform this role.
Although validators and miners help create blocks, they represent only a subset of the wider node network. Most full nodes simply verify transactions and blocks to ensure the blockchain follows its rules.
Why Crypto Applications Need Blockchain Node Providers
Web3 applications need reliable access to the blockchain. Every time users submit a transaction, check wallet balance, or interact with a smart contract, nodes handle these requests.
While any team can run its own nodes, doing so quickly becomes a significant operational burden. Instead of focusing on building product features, engineering teams must devote time and resources to managing blockchain infrastructure.
Running blockchain nodes introduces several ongoing challenges, including:
1. Storage and Hardware
Blockchain data grows continuously as new blocks are added. Nodes require powerful hardware, fast SSD storage, and sufficient computing resources to keep pace with the network. As applications grow, infrastructure must scale alongside them to meet increasing demand.
2. Maintenance and Monitoring
Nodes require constant attention. Teams must install client updates, monitor performance, manage storage, troubleshoot synchronization issues, and recover from outages. A node that falls behind or goes offline can prevent an application from serving accurate blockchain data.
3. Reliability and Performance
Users expect applications to be fast and always available. Maintaining highly available, low-latency blockchain infrastructure often requires redundant nodes, load balancing, monitoring, and failover systems to ensure uninterrupted service.
4. Supporting Multiple Blockchains
Modern applications rarely operate on a single blockchain. Supporting Ethereum, Base, Arbitrum, Solana, BNB Chain, and other networks means running and maintaining separate infrastructure for each one, each with its own software, upgrade schedule, and operational requirements.
Rather than managing these complexities and operational overheads, most projects rely on blockchain node providers who abstract away the underlying infrastructure, allowing teams to focus on building applications. By outsourcing blockchain connectivity, projects simplify operations but also introduce a dependency on third-party infrastructure.
Who are Blockchain Node Providers?
Blockchain node providers are companies that operate and manage blockchain nodes as a service, exposing them via RPC endpoints so developers can connect their applications to blockchain networks without running or maintaining nodes themselves.
Rather than operating a single node, providers typically manage fleets of full nodes, archive nodes, and supporting infrastructure designed for high availability, low latency, and scalability. Many also support dozens of blockchain networks, making it easier for projects to build and scale multi-chain applications through a single provider.
Some of the leading blockchain node providers include:
- QuickNode
- Alchemy
- Infura
- Helius
- Chainstack
- Ankr
- GetBlock
- dRPC
How Web3 Applications Connect to Blockchains
Blockchain node providers sit between Web3 applications and the blockchain, handling the infrastructure that makes blockchain communication and gives applications access to the blockchain network via RPC Endpoints
RPC Endpoints
Source: Dexterlabs
An RPC endpoint is simply a type of API. It’s the API URL an application uses to communicate with a blockchain. It exposes a blockchain’s JSON-RPC interface, allowing developers to read blockchain data and submit transactions without interacting directly with the blockchain’s peer-to-peer network.
Every blockchain interaction, from checking an account balance to executing a smart contract, passes through an RPC endpoint.
RPC Nodes
An RPC node is the backend blockchain node that processes requests from external applications. In most cases, it is a full node or archive node configured to expose a Remote Procedure Call (RPC) interface to external applications.
In short:
- RPC endpoint: The API URL your application connects to.
- RPC node: The backend blockchain node, or cluster of nodes, that processes those requests.
For large infrastructure providers, a single RPC endpoint often sits behind load balancers and distributed infrastructure that route requests across multiple full and archive nodes.
To developers, it appears as a single endpoint, but behind the scenes, it is typically an entire network designed for reliability, scalability, and low latency.
How the Request Flows
A typical blockchain request follows a simple path:
- A wallet, dApp, or backend application sends a request to an RPC endpoint.
- The node provider routes that request to one of its backend RPC nodes.
- The node validates the request, reads blockchain data, or broadcasts the transaction to the network.
- The result is returned through the RPC endpoint back to the application.
This architecture allows developers to build blockchain applications without operating their own node infrastructure while still benefiting from reliable, scalable access to multiple blockchain networks.
Security Challenges and Risks Associated with Third-Party Node Providers
Since many projects depend on node-as-a-service, the security and configuration of these services become part of the application’s overall security posture.
Some of the key risks include:
1. Data Integrity and Manipulated Responses
Applications trust RPC providers to return accurate blockchain information. If that data source is compromised or manipulated, applications may make incorrect decisions based on false information.
A notable example is the 2026 KelpDAO incident, where attackers compromised RPC infrastructure used by LayerZero’s verification system and manipulated the data being provided to the protocol. The smart contracts executed correctly, but they acted on incorrect information supplied through compromised infrastructure.
This highlights an important security principle: audited smart contracts can still be exposed if the external infrastructure they depend on provides unreliable data.
2. Single Provider Dependency
Many applications begin with a single RPC provider because it is simple and cost-effective. However, depending entirely on one provider creates a central point of failure.
If that provider experiences:
- downtime,
- performance degradation,
- infrastructure compromise,
- or configuration errors,
the application may inherit those problems.
Using multiple independent providers, health checks, and intelligent routing can reduce this risk.
3. API Key Exposure
RPC providers commonly authenticate requests through API keys. If these credentials are exposed through frontend code, public repositories, or insecure configuration, attackers may abuse the endpoints or exhaust allocated resources.
Poorly configured RPC endpoints can also expose unnecessary access or create opportunities for abuse. Proper secret management, access controls, rate limiting, and monitoring are essential when integrating third-party blockchain infrastructure.
The Security Takeaway
Blockchain node providers are essential infrastructure for modern Web3 applications, but they should not be treated as a black box. Teams must evaluate how these dependencies are configured, monitored, and secured.
Hashlock Secures the Infrastructure Behind Your Web3 Application
Blockchain applications are only as reliable as the infrastructure they depend on. Smart contract security is only one part of building a resilient Web3 application. Teams must also consider the security of the infrastructure supporting their applications, including RPC providers, APIs, oracles, and other third-party services.
At Hashlock, we help Web3 teams strengthen their security posture through smart contract audits, penetration testing, and supply chain infrastructure reviews. By identifying risks across both code and critical dependencies, we help projects build applications that are more secure, reliable, and prepared for real-world usage.
Build with confidence. Secure the infrastructure your Web3 application relies on.
Also read: Your Audit Won’t Stop an RPC Attack. Here’s What Will
