We have already covered the major portion of gasless transactions in the last part . So, in this part we will look at the tools we have to implement gasless meta transactions in our dapp.

First, Let's talk about GSN 

But what the heck is this new term GSN !

GSN stands for Gas Station Networks. It is nothing but a decentralized network of relayers and they pay for gas fees on our behalf .

Gasless transactions are made possible by a network of Ethereum relayers.

What is a relayer? When you attempt to make a transaction on the Ethereum blockchain, your transaction needs to be processed by the miners in order to get written on the blockchain. These miners are incentivized to process your transaction since they can collect gas fees for their work. That’s where relayers come in - they relay your transactions to the miners and collect your gas payment for you. They allow you to effectively skip two steps (sending ETH and then broadcasting a transaction) when using MetaMask.

When you use MetaMask with Gasless, it will automatically send your transaction through one of these relayers who will charge 0%, usually 1% or 2% with some networks offering different rates depending on what type of token is being used. It’s important to note that while Gasless allows you to send transactions without having any ETH in your wallet, this doesn’t mean that no gas was used or paid for - it just means that it wasn’t paid for from within your wallet but rather from somewhere else like an external source or reserve (gas fee pools) implemented by dApps or DEXes themselves, another user or even a pre-funded account linked up within MetaMask itself.

A GSN is an EIP 1193 compliant infrastructure that allows dapps to delegate gasless transactions to relayers running in the GSN. In other words, the relayers pay for each transaction, with the dappmaker reimbursing them in some way; the dapp can either reimburse the relayer with funds deposited by the user through the dapp (e.g., wallet or exchange), or tokenize some piece of the value offered by their application, and reimburse the relayer with that token.

The advantages of GSN are :

1. The user can pay gas in any token.

2. It allows users to pay for gas in fiat without going through the hassle of KYC.

3. Allow dapps to subsidize the onboarding process for new users

To know more about gsn, head over to 

https://docs.opengsn.org/#the-problem

Now, let's look at the easy way to implement gasless tranasactions 

Gasless meta transactions with Biconomy

Biconomy is a relayer network for blockchain applications that provides a layer abstraction over the blockchain. Developers can use Biconomy to build scalable blockchain applications without having to worry about managing keys, gas, metamask pop-ups, and long transaction times. In short, Biconomy is a one stop shop and easy way to integrate the entire meta-transaction stack into your application.

Biconomy allows you to transact on blockchains like Ethereum or Matic Network securely with no risk of failure due to a lack of funds or fluctuating gas prices. In addition, it reduces development time by allowing developers to focus on building their apps rather than managing key and account management complexities, along with transaction handling logic.

Biconomy has a simple user interface which makes it easy for developers to develop and ship gasless dapps.

To dive deep and understand more about biconomy relayer infrastructure 

Head over to this link.

Now , Let's compare the two methods to get a better understanding of what to choose for our Dapp.

GSN Pros:

• Decentralized system, so no need to trust any single relayer.
• GSN2 is simpler than GSN1, so comparatively easy to set up.
• Relayers can be paid in ERC20 tokens while paying back the fees.

GSN Cons:

• Extra setup is required.
• High relayers fees.
• Regular monitoring of DApp funds is required to repay the relayers.
• High transaction fee, as extra processing is done on chain like multiple hops, checking dapp deposits, relayer payments.
• 70 cents costlier than Biconomy, per transaction.

Biconomy Pros:

• Dashboard for developers to more granular control on meta transaction usage.
• Quick 2 step integration with no extra smart contract deployments.
• No need to worry about protocol changes or new trends on blockchain. Biconomy makes sure the system is up to date with market trends.
• Less gas per transaction as no extra hops on-chain and payments are processed off-chain.
• Gas fee can be paid in stable tokens or ERC20 tokens.
• You can do network agnostic transactions - No need to change RPC URL in Metamask while doing transactions on Layer2

Biconomy Cons:

• Not decentralized, so need to trust Biconomy servers for relaying transactions.

We have now successfully covered the why,what and how of gasless transactions.

Now it's your turn to decide which method to choose for implementing gasless transactions for your dapp

Keep learning , keep exploring