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Ali Murtaza
Ali Murtaza

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What are Oracles? & How is Chainlink Leading to Provide Optimal Solutions?

“Understanding the Role of Data Connectivity in Decentralized Applications and Chainlink’s Innovations in Meeting Industry Demands”

Smart contracts cannot access real-world data directly because they are executed within a blockchain network, which is a self-contained environment that operates independently of external systems. The purpose of a blockchain network is to maintain a distributed ledger of transactions that is secured through cryptography and consensus algorithms. To access data from external sources, smart contracts need to rely on intermediaries known as oracles.

What is an Oracle?

An oracle is a mechanism in blockchain technology that connects the blockchain to off-chain data sources such as APIs or real-world events.

A blockchain is a distributed database that relies on participant consensus to validate transactions and keep a single version of the truth. Blockchains, on the other hand, are typically isolated from external data sources and cannot directly access information from the outside world. This limitation can be problematic for applications that require information from external sources to execute smart contracts or other blockchain operations.

An oracle acts as a connector between the blockchain and external data sources, allowing blockchain applications to access real-world data. Oracles typically receive data from off-chain sources and transmit it to the blockchain in a format that smart contracts and other applications can use.

Key Considerations for Choosing a Blockchain Oracles

Despite the number of options available in the Web3 space, selecting the right Blockchain Oracle solution provider is a critical step for the success of your decentralized applications.

Here is a list of factors to consider:

  • Decentralization: It is a crucial factor to consider when selecting a Blockchain Oracle solution provider. Centralized oracles can pose a significant risk, as they have the power to control the data utilized in your dapps. This can be especially problematic for applications such as DeFi, where the financial assets of users are at stake.

  • Data Quality: It is critical to ensure the accuracy and dependability of Oracle data consumed by dapps. It is critical to ensure that the data is of high quality, up to date, and derived from reliable and authenticated sources. Failure to do so may seriously damage the financial assets of your users, and will risk the dapp’s success.

  • Security: Ensuring the security of the data provided by an oracle that feeds into your decentralized applications (dapps) is very important. A compromised oracle solutions provider not only compromised its own solutions but also endangers the integrity of your dapps and their users. Such a scenario is commonly referred to as an “Oracle Attack” in the blockchain industry. To safeguard against this risk, it is important to opt for a decentralized oracle with a proven track record of security and robust measures in place to protect both their systems and the data provided to your dapps.

  • Cost: As we know that each blockchain transaction has a real financial cost, it is critical for dapp developers to choose an oracle solution provider that not only satisfies the above-mentioned requirements but also takes into account the particular requirements and preferences of their dapps and user base.

While there may be additional factors to consider, the above-mentioned criteria are the primary considerations that should guide the selection of an oracle for your dapp.

How is Chainlink Leading to Provide Optimal Solutions?

The Chainlink Network is composed of the highest-quality, Sybil-resistant oracle nodes that are operated by leading DevOps and security teams, such as Deutsche Telekom’s T-Systems, who have decades of experience running mission-critical infrastructure. The security-reviewed and tamper-resistant nodes that comprise Chainlink oracle networks are highly transparent. Their performance metadata is made publicly available to users and can be found on-chain or on third-party sites such as

Chainlink also employs a defence-in-depth approach where multiple security solutions are used in combination to increase oracle network robustness and reliability. This includes privacy-preserving cryptography like DECO, trusted hardware such as Town Crier, crypto-economic security through implicit/explicit staking, and much more.

We previously discussed the importance of decentralization, high-quality and up-to-date data, security, and cost-effectiveness in an oracle solution provider. In each of these areas, Chainlink has made significant strides to offer optimal solutions for dapps.

Here are some of the ways:

  • Decentralized Oracle Network: The Chainlink Network is made up of multiple decentralized oracle networks running simultaneously and independently of one another. For example, if a smart contract requires data about the price of ETH/USD, instead of relying on one individual blockchain oracle to pull price data from one API source, the smart contract can use a decentralized oracle network to have multiple oracle nodes pull data from several different API sources and then aggregate the result. Through decentralized computation, Chainlink-powered decentralized oracle networks provide users superior security and reliability guarantees on the inputs and outputs of their smart contract, ensuring that both on-chain and off-chain components of a decentralized application are tamper-proof end-to-end.

  • Reputation System: By rewarding nodes for good behaviour and punishing them for bad behaviour, Chainlink’s reputation system encourages nodes to provide accurate data. This makes it possible to guarantee that nodes only offer reliable, high-quality data.

  • Multiple Data Sources: Chainlink aggregates data from multiple sources to ensure that the data is accurate and trustworthy. This helps to mitigate the risk of any single source being compromised or providing incorrect data.

  • Data Verification: Chainlink offers a variety of data verification methods, including cryptographic proofs and on-chain verification, to ensure that data is accurate and has not been tampered with.

  • Audits: Chainlink is subjected to regular audits by reputable third-party firms to ensure the system’s security and lack of vulnerabilities. This helps to ensure that data quality and system reliability are maintained.

Chainlink’s Products

Data Feeds

Chainlink Data Feeds are decentralized oracle networks that provide aggregated financial market data used by leading DeFi applications such as Aave, Synthetic, Compound, and more. Powered by a multitude of professional, security-reviewed oracle nodes and premium data aggregators, these purpose-built price feeds provide broad market coverage on a wide array of assets and enable developers to rapidly create innovative smart contract applications that require a secure source of external market data.

Chainlink Data Feeds are a community resource sponsored by a large collection of users and Chainlink, creating highly secure and decentralized oracle networks through the aggregation of user fees. With each additional user, existing and future users gain the benefits of a more cost-efficient and secure oracle network than they could afford on their own. As the DeFi ecosystem has grown, Chainlink Data Feeds have become a widely adopted solution that is lowering the barrier to creating highly secure financial smart contract applications.

Verifiable Random Function (VRF)

Chainlink VRF brings secure random number generation to the blockchain. Chainlink VRF solves the difficult problem of providing an on-chain source of randomness that is publicly verifiable to be authentic and tamper-proof. Many smart contracts are augmenting the value they can create by utilizing Chainlink VRF, specific applications such as gaming dApps that must prove to their users that their source of randomness is provably fair and resistant to manipulation from any external entity. Chainlink VRF enables and accelerates the development of smart contracts focused on blockchain gaming, security, layer-two protocols, and various other use cases.


Chainlink Automation is a decentralized solution that enables projects to run key smart contract functions and DevOps tasks automatically in a highly reliable, trust-minimized, and cost-efficient manner. Individual developers, teams, and DAOs can utilize Chainlink Automation as an off-chain computation layer to reliably perform key functions and unlock advanced utility.

A decentralized network of nodes provides trust-minimized and reliable automation with no single point of failure, mitigating risks around manual interventions or centralized servers. Projects using Chainlink Automation are able to reduce time spent on DevOps, eliminate automation infrastructure costs, and build faster and more efficiently.


Chainlink Functions provides our smart contracts with access to a trust-minimized compute infrastructure. Our smart contract sends our code to a Decentralized Oracle Network (DON), and each DON’s oracle runs the same code in a serverless environment. The DON aggregates all the independent runs and returns the final result to our smart contract. Our code can be anything from simple computation to fetching data from API providers.

Chainlink Functions provides access to off-chain computation without having to run and configure our own Chainlink Node. To pay for requests, we fund a subscription account with LINK. Our subscription is billed only when the DON fulfils our request.


Connecting to any API with Chainlink enables our contracts to access any external data source through Chainlink’s decentralized oracle network. Making smart contracts compatible with off-chain data adds to the complexity of building smart contracts. Due to that, Chainlink has created a framework with minimal requirements, yet unbounded flexibility, so developers can focus more on the functionality of smart contracts rather than what feeds them. Chainlink’s decentralized oracle network provides smart contracts with the ability to push and pull data, facilitating the interoperability between on-chain and off-chain applications.

Whether our contract requires sports results, the latest weather, or any other publicly available data, the Chainlink contract library provides the tools required for our contract to consume it.


In conclusion, oracles play a crucial role in enabling smart contracts to access and interact with external data sources, making them more powerful and versatile. However, the accuracy and security of these oracles are critical for the success and adoption of decentralized applications, especially in the rapidly growing DeFi space.

Thank you for reading this article, which provides an introduction to oracles, Chainlink, and its products. In future articles, we will delve deeper into Chainlink’s products and explore their technical implementation.

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