Ethereum Stack Exchange is a question and answer site for users of Ethereum, the decentralized application platform and smart contract enabled blockchain. It only takes a minute to sign up.
Sign up to join this community
I came across this statement online in one of the articles "In order to read, you need to verify the chain". I am not able to comprehend this statement. Does that mean I should always run a node to be able to read?
What about using remote clients? How is using remote clients not trustless?
The statement "in order to read, you need to verify the chain" most likely refers to light nodes - or clients. From the docs:
The purpose of the light client protocol is to allow users in low-capacity environments (embedded smart property environments, smartphones, browser extensions, some desktops, etc) to maintain a high-security assurance about the current state of some particular part of the Ethereum state or verify the execution of a transaction.
There are many differences between light and full nodes, but, primarily, it's about what data is synchronised. A light node syncs much less information than a full node, but that information is enough to verify that the data received from a full node isn't tampered with.
It's worth looking into block headers and merkle trees, especially the latter, because that's what's being used here.
To be able to read from the blockchain you do not need to verify it. If you trust in your data supplier then it is ok to not verify that data.
But one of the features of the blockchain it is you can use without trusting in other network participants. Every data you read from the blockchain can be verified with a cryptography proof.
If you are working in an unsecured environment with other participants that you do not have a trust relationship with, then it is encouraged to verify all the blockchain data.
