# Chih-Cheng Liang | Introducing Sparse Merkle Tree

- Speakers: [Chih-Cheng Liang](https://streameth.org/speakers/chih-cheng-liang)
- Channel: [Taipei Ethereum Meetup](https://streameth.org/taipei-ethereum-meetup)
- Date: 2021-10-09
- Duration: 34:23
- Topics: ethereum
- Watch: https://streameth.org/watch/yt-NfBx_vLcM7s
- YouTube: https://www.youtube.com/watch?v=NfBx_vLcM7s

## Description

Speaker intro
Chih-Cheng Liang builds zero-knowledge proof applications on Ethereum.

Talk description
"Introducing Sparse Merkle Tree"
Layer 2 technology centers around outsourcing the data storage from the decentralized L1 full nodes to a centralized L2 coordinator. The commitment scheme is the technology to achieve that while preserving security.

In this talk, we introduce the Sparse Merkle Tree, a particular hash tree commitment that is popular among many L2 implementations and easy to reason. We will take a baby step to walk through the membership proving and updating, which gives the idea, the background, and contexts to understand an essential part of L2 design space.