The ecosystem of DeFi and Web3 applications has been going through a radical transformation, with new solutions arriving almost every day. On the one hand, you have peer-to-peer lending platforms and decentralized crypto exchanges, while on the other, NFTs and web3 games have created opportunities for web3The importance of testnets explained in the web3 landscape would revolve around ensuring security and desired functionalities for developers. Developers can rely on testnets to ensure the functionality and security of smart contracts and decentralized applications.

The testnets provide the advantage of working with the same client as on the mainnet, albeit while working on a different ledger. The isolation of testnets ensures that the testnet crypto expenditure is zero. Unlike the mainnet, developers don’t have to pay actual crypto for deploying smart contracts and dApps on testnets. Therefore, it is clearly evident that testnets can transform blockchain development with cost-efficient workflows and other noticeable advantages. The following post will help you understand testnets, their working, and examples of popular testnets.

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Definition of Testnets

Testnets, or test networks in blockchain, are networks that can work and serve similar functionalities as main networks. The most important aspect in answers to “What are testnets?” would also refer to the way they work on a different ledger other than the mainnet. As a result, the coins or cryptocurrency on a testnet do not have any impact on transactions or value exchanged on mainnet. Developers can use testnets for deploying, testing, and executing projects on a selected blockchain network. 

You should remember that the cost of failures or errors on the mainnet can be extremely high. In addition, the failures in mainnet are also irreversible in certain use cases where developers can find an environment for working comfortably without risks. The answers to “Are testnet coins worth anything?” would point to the ways in which testnets allow the flexibility of deploying and checking app functionalities. 

For example, security is one of the foremost priorities for all developers involved in creation of decentralized solutions. Deploying a blockchain app on a testnet can provide the advantage of identifying vulnerabilities associated with the platform. In addition, the testnet can provide a clear impression of the ways in which the blockchain-based solution worked. Testnets for pre-network improvements require evaluation of functionality with the new changes.

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How is Testnet Different from Mainnets?

The working of a testnet showcases how they are different from mainnets in blockchain. You can suggest answers to “What is testnet used for?” with a detailed understanding of differences between mainnets and testnets. One of the simple ways to outline the difference between mainnet and testnet is to describe mainnet as the main exam while testnet represents mock exams. Before you prepare for the main exam, you need to use mock exams to test your knowledge. Similarly, blockchain developers must use the testnets to evaluate the functionalities of their applications before deploying them. 

Mainnet or main network of a blockchain platform includes only one seamless wallet system applicable for the complete network. On the contrary, the fundamentals of testnets explained for beginners would showcase the use of distinct wallet systems in each testnet. The individual wallet systems ensure easier management of coins and transactions beyond the scope of the mainnet. In addition, you can recognize the testnets with distinct network IDs. The Ethereum network allocates network ID 1 to the Ethereum mainnet. On the other hand, the testnets have different network IDs, such as 3 for Ropsten and 4 for Rinkeby testnet.

The IDs for testnets help in ensuring that the system deploys contracts to the desired network with the use of correct wallet systems. Another important point of difference between mainnet and testnets is the transaction frequency. On top of it, the transactions on testnets are not published for the public owing to the necessity of changes. 

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Design of Testnets

The detailed responses to “What are testnets?” show how they can serve as test networks by providing an alternative blockchain. The alternative blockchain mirrors the capabilities of the original blockchain or mainnet for providing a safe environment to test and experiment with applications for reducing errors during production. 

You can find similarities between testnets and the staging environments used in conventional web development workflows. Just like the staging environment, blockchain developers can use testnets for evaluating protocol upgrades and smart contract codes before deploying them on the main network.

It is important to note that certain test networks utilize the consensus mechanisms and technologies of their parent network. On the other hand, variable responses to “What is testnet used for?” can also point to possibilities of testnets using different consensus mechanisms and technologies. Depending on the extent to which testnets simulate the mainnet, the design of testnets can incorporate unique consensus mechanisms and technologies.

Origins of Testnets

The next important aspect of an introduction to testnets would revolve around the origins of the mainnet simulation networks. The first testnet, Olympic, was launched in early 2015 for the Ethereum blockchain. It offered a Proof of Work-based test network intended as the final test required before public release of Ethereum mainnet. Ultimately, the Olympic testnet was discontinued after the public launch of Ethereum mainnet. 

In the next phase of the testnet crypto evolution, developers came across the Morden testnet. The launch of Ethereum mainnet prompted the urgent necessity for a new public test network. Morden testnet used the Proof of Work consensus mechanism, albeit with a different network structure. It served as the sole Ethereum testnet for almost a year till November 2016. Even after its discontinuation, the Ethereum Classic community continued using the Morden Classic test network. The early test networks provided the benchmarks for other testnets which came after them and ruled the blockchain development landscape. 

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Top Testnets on Ethereum Network 

The demand for blockchain and web3 development is going through an upward trend, with many new projects emerging in recent times. However, the most important task, i.e., coding smart contracts and executing them on mainnet, can be the trickiest challenge for developers. You can reflect on answers for “Are testnet coins worth anything?” to understand how testnets solve the challenges for developers. Nobody would like to spend their valuable resources on gas fees for testing their smart contracts on the mainnet. 

On top of it, deploying smart contracts on the mainnet makes them irreversible. Testnets provide free cryptocurrency, which you can use only on testnets for paying gas fees on the testnets. Remember that you cannot use the testnet crypto on the mainnet. Developers can review the functionalities of individual components of their smart contracts with testnets. At the same time, you must also know the most popular testnets and how you can use them. Here is an overview of the top testnets used on the Ethereum blockchain network. 

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  • Rinkeby 

The Rinkeby testnet was introduced in April 2017 as a long-term solution based on the Proof of Authority consensus mechanism. With the new Proof of Authority consensus mechanism, developers can find the advantages of easier implementation and embed with existing Ethereum clients. The introduction to testnets explained in detail would also point to the utilization of existing sync technologies such as Warp, Light, and Fast. Therefore, it does not impose pressure on client developers to add custom logic to the applications. 

The Geth developer team maintains the Rinkeby test network. You can use the official website of Rinkeby to view the details of the Rinkeby network. It showcases the network stats alongside the number of nodes, blocks, and transactions. On top of it, the testnet can also show the details of the number of transactions each second and number of blocks processed each second. Rinkeby also showcases the number of peers or the nodes connected with the testnet. 

You can find responses for “What is testnet used for?” in the flexibility for using a block explorer on the Rinkeby website. The block explorer can showcase details of the blockchain in a human-readable format. Developers can use a Metamask extension for writing and deploying a smart contract on Rinkeby testnet. 

Once you have opened your Metamask account, you can choose the Rinkeby testnet option from the list of other testnets. Subsequently, you can copy the Ethereum address and use the faucet to obtain free ETH. In addition, you can also leverage third-party sites to obtain free ETH on the Rinkeby testnet. The Rinkeby faucet involves simple tasks for obtaining free ETH, such as publishing social media posts for the Rinkeby testnet.                

You must note that Rinkeby testnet takes a significant amount of time to provide free ETH. It also uses the Geth client only for transactions, thereby creating limitations for testing. However, the Proof of Authority consensus mechanism of Rinkeby testnet has been gaining popularity in the blockchain landscape. 

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  • Kovan 

The next important testnet for Ethereum network is Kovan, which is a fork of the Ethereum mainnet. The Ethereum Foundation created Kovan in June 2017. It is also under the maintenance of Geth developer team, just like Rinkeby testnet, alongside using the Proof of Authority consensus mechanism. The explanation of ‘What are testnets?’ with the example of Kovan would also reflect on the similarities in features of Rinkeby and Kovan testnets. The testnet allows the use of an official faucet for obtaining free ETH on Kovan test network. 

Kovan allows the flexibility for writing contracts for tokens according to ERC-20, ERC-1155, and ERC-721 token standards. You can also find details about the latest blocks and transactions alongside the tokens. Kovan also helps in searching for transactions, blocks, addresses, and other important pieces of information. 

The testnet crypto token you receive on Kovan testnet is known as Kovan Ether. You can rely on the official faucet, the Kovan Gitter chat room, or the Github account. Kovan presents a distinction from the Ethereum mainnet with the use of a proof of authority consensus mechanism, which is different from Ethereum mainnet. The biggest advantage of Kovan testnet reflects the easy methods for obtaining free ETH.

  • Ropsten 

The Ropsten testnet is also similar to the Kovan and Rinkeby testnet in terms of design. However, it is one of the closest to the Ethereum mainnet in terms of design as it uses a Proof of Work consensus mechanism. The test network had to shut down in February 2017 following a security attack. 

An attacker increased the gas limit to 200 million, thereby escalating the mining reward to 12 ETH. You might have doubts about “Are testnet coins worth anything?” upon hearing about security attacks on testnets. Ultimately, the Ropsten testnet resumed operations in August 2017 as the attack was stopped. 

The most noticeable benefit of utilizing Ropsten in comparison to other testnets is the similarity with Ethereum mainnet. You will notice that the consensus mechanism of Ropsten is the same as the Proof of Work consensus of Ethereum before the Merge. Therefore, Ethereum developers are more likely to capitalize on advantages of operating the testnet without any complications. On top of it, Ropsten is compatible with Geth and Parity clients, which makes it more flexible than other testnets. Ropsten also offers the advantage of obtaining testnet ETH faster than other test networks. 

  • Goerli

The Goerli testnet is another latest addition among Ethereum test networks. It was introduced in November 2018 and utilizes Proof of Authority mechanism. The Goerli testnet offers compatibility with different ETH clients alongside inheriting the benefits of Proof of Authority consensus. 

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The overview of an introduction to Ethereum testnets points to the fundamentals of testnets explained in detail. Testnets or test networks are simulations of the mainnet or main network. Developers can use testnets for deploying smart contracts without incurring hefty costs in gas fees. On the contrary, testnets follow a different wallet system, where you can use fake cryptocurrency for executing smart contracts and blockchain applications. 

You don’t have to worry about financial consequences of testing your smart contract again and again on the testnet. Ultimately, developers can come up with a refined solution by leveraging testnets without incurring massive costs. As a result, testnets are crucial for the long-term growth of blockchain and web3 ecosystem. Learn more about testnets and smart contract development with professional training courses now.      

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*Disclaimer: The article should not be taken as, and is not intended to provide any investment advice. Claims made in this article do not constitute investment advice and should not be taken as such. 101 Blockchains shall not be responsible for any loss sustained by any person who relies on this article. Do your own research!