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Disclaimer: I work on Ethereum core development. One of the coolest things happening that will be available to everyone over the coming year is something called

by rauljordan2020 5y ago

Disclaimer: I work on Ethereum core development. One of the coolest things happening that will be available to everyone over the coming year is something called a light client, which is essentially a very light, validating node that tracks the head of the chain with certainty, and can be used as an alternative to services such as Unfura. In the future, Metamask will probably be a light client that actually tracks the head of the chain and can validate proofs of user account state. Source: https://github.com/ethereum/consensus-specs/blob/dev/specs/altair/sync-protocol.md https://github.com/ethereum/consensus-specs/blob/dev/specs/a...

littlestymaar 5y ago
> light client, which is essentially a very light, validating node that tracks the head of the chain with certainty How does that work?
- kamray23 5y ago
  Skip over verifying everything and only verify a subset of all things you care about. Use alternative root nodes you trust instead of verifying. Stuff like that. They have a spec: https://eth.wiki/concepts/light-client-protocol https://eth.wiki/concepts/light-client-protocol
- keymone 5y ago
  It works by surrendering any pretense of eth being a decentralized cryptocurrency and turning every node into a glorified and bloated transport/identity layer. If you’re not validating transactions - you’re trusting a third party. There are no light clients that avoid this problem. It remains to be seen if they are even possible.
- rauljordan2020 5y ago
  Sorry it took me ages to clarify this. It's actually a pretty cool mechanism! What I mean by "tracking the head of the chain with certainty" means that you don't have any trust assumptions on the head block. If you track the latest head block, that means you can verify Merkle proofs of the chain state (as the state root is a field embedded in a block). This is neat because a light client, using low resource requirements, can tell verify a proof of some state data you present it. The way it works is that there is a committee of validators in the consensus protocol that is required to sign the head of the chain. We use cryptography known as BLS signatures to perform signature aggregation, meaning you can verify a single signature to ensure that whole committee is correct. The state of the chain can be represented as a Merkle trie, and we can obtain the actual committee as a branch of this tree which can be used during the verification process. https://medium.com/chainsafe-systems/lodestar-releases-light-client-prototype-40f300361c65 https://medium.com/chainsafe-systems/lodestar-releases-light... It's really neat and there are working prototypes out there today.

littlestymaar 5y ago

> light client, which is essentially a very light, validating node that tracks the head of the chain with certainty How does that work?

kamray23 5y ago
Skip over verifying everything and only verify a subset of all things you care about. Use alternative root nodes you trust instead of verifying. Stuff like that. They have a spec: https://eth.wiki/concepts/light-client-protocol https://eth.wiki/concepts/light-client-protocol
keymone 5y ago
It works by surrendering any pretense of eth being a decentralized cryptocurrency and turning every node into a glorified and bloated transport/identity layer. If you’re not validating transactions - you’re trusting a third party. There are no light clients that avoid this problem. It remains to be seen if they are even possible.
rauljordan2020 5y ago
Sorry it took me ages to clarify this. It's actually a pretty cool mechanism! What I mean by "tracking the head of the chain with certainty" means that you don't have any trust assumptions on the head block. If you track the latest head block, that means you can verify Merkle proofs of the chain state (as the state root is a field embedded in a block). This is neat because a light client, using low resource requirements, can tell verify a proof of some state data you present it. The way it works is that there is a committee of validators in the consensus protocol that is required to sign the head of the chain. We use cryptography known as BLS signatures to perform signature aggregation, meaning you can verify a single signature to ensure that whole committee is correct. The state of the chain can be represented as a Merkle trie, and we can obtain the actual committee as a branch of this tree which can be used during the verification process. https://medium.com/chainsafe-systems/lodestar-releases-light-client-prototype-40f300361c65 https://medium.com/chainsafe-systems/lodestar-releases-light... It's really neat and there are working prototypes out there today.