RSK Community Call - October 2021 Summary
Tags: rsk, blockchain, bitcoin
Published: 2021-11-08 12:52:29

_About RSKj v3.1.0, Aggregation & parallel transaction processing, and Rollup-optimized Ephemeral Call data._

On 29th October 2021, The RSK Ecosystem held its fourth community call. The aim of these community calls is to discuss the [RSK Improvement Proposals - RSKIPs](https://github.com/rsksmart/RSKIPs), get the community involved, gather feedback, discuss the RSK consensus protocol, the formal process for proposing improvements, and the upcoming network upgrades. For more info, read the [RSKIP Purpose and Guidelines.](https://github.com/rsksmart/RSKIPs/blob/master/IPs/RSKIP0.md) 
  
It was live-streamed on several platforms, thanks to everyone who joined the Livestream! For those of you who missed out on attending it live, visit the links below;

🎥 Watch the [RSK Community Call October 2021](https://youtu.be/mdCinpZ7Qcg) on Youtube (Replay).

🗣️ Propose your own [RSKIPs](https://github.com/rsksmart/RSKIPs)

🔗 Join the [RSK Research & Innovation Forum](https://research.rsk.dev)

🗣️ [Suggest RSKIPs to discuss](https://research.rsk.dev/t/community-call-july-august-2021/204/2) in the next community call

🔗Join our [Open Slack Community](https://developers.rsk.co/slack/) and ask your questions in #research-and-innovation.

The speakers on this call were:

- Diego Masini
- Adrian Eidelman
- Sergio Demian Lerner
- Brendan Graetz

In this call, we discussed:
-  [The recent RSKj v3.1.0 release](https://github.com/rsksmart/rskj/releases/tag/IRIS-3.1.0)
- Aggregation: fast and cost-effective peer-to-peer payments
- Parallel transaction processing: block processing as fast as possible 
- [RSKIP-281: Rollup-optimized Ephemeral Calldata](https://github.com/rsksmart/RSKIPs/blob/master/IPs/RSKIP281.md)

    
### The RSKj v3.1.0 Release

Adrian Eidelman talked about the release of RSKj v3.1.0. He said this release contains several enhancements in JSON-RPC interface, Ethereum compatibility fixes and node performance improvements, among other things. Also, some of the improvements introduced in this release came from community contributions made within the past [RSK Hackathon: Building the Future On Bitcoin](https://gitcoin.co/hackathon/rsk-hack/) on the Gitcoin platform.

This release is a non-mandatory upgrade, however, you should consider updating to benefit from the enhancements and new features.

See related links:
- See more details about the [RSKj v3.1.0 release milestone](https://github.com/rsksmart/rskj/milestone/25) 
- [Releases page](https://github.com/rsksmart/rskj/releases/tag/IRIS-3.0.1https://github.com/rsksmart/rskj/releases/tag/IRIS-3.0.1)


### Aggregation: fast and cost-effective peer-to-peer payments

![Deposit Accepted](https://dev-to-uploads.s3.amazonaws.com/uploads/articles/59susg4w663v81isz476.jpg)

Diego Masini spoke about the work done on Aggregation, which is a fast and Cost-effective payment system. He said it is a layer 2 scalability solution for RSK and its main goal is to process transactions off-chain, bundle them in batches and post a validity proof for these batches to the blockchain. This solution ensures that the layer 2 transactions are secured by the blockchain and we can transact much faster. He mentioned two potential approaches to this solution which includes; optimistic rollups and Zero-Knowledge (ZK) rollups, he said the method of verification between these two approaches is the key distinction.

### Parallel transaction processing: block processing as fast as possible

![Multithreading](https://dev-to-uploads.s3.amazonaws.com/uploads/articles/8tht3xv23vxb318mbh2i.jpg)

Diego Masini also spoke about the ongoing work on parallel transaction processing, which enables processing a block as fast as possible. This enables transactions to be split into different partitions, and each partition could be executed in parallel. The main goal of this approach is to process as many transactions per block as possible and also reduce synchronization time.

### RSKIP-281: Rollup-optimized Ephemeral Call data

![Ephemeral Call Data Banner](https://dev-to-uploads.s3.amazonaws.com/uploads/articles/7de9j49mi0axx5zkhkyf.jpg)

The [RSKIP-281](https://github.com/rsksmart/RSKIPs/blob/master/IPs/RSKIP281.md) is an improvement over RSKIP214 and RSKIP28. It enables sending data to contracts called ephemeral data and enables the disposal of this data at a later block.

Sergio Lerner introduced the RSKIP-281. He noted that this research began in 2016 and it is about the optimization of the RSK blockchain to better serve as a data availability layer for rollups. He said this proposal is very efficient and can provide gas savings for rollups such as Aggregation. An ephemeral call data, is similar to the call data, but gets a discount in gas costs because it is only temporarily available for smart contracts to query. The use cases for this kind of data is;

- Data to be challenged over a period (optimistic computations)
- Immediate availability of datasets that accept a later compression

Both occur in Zero Knowledge (ZK) and Optimistic Rollups

He mentioned two flavours of this type of data; 

1. Remove by Default (initially cheap, pay more to preserve data)
2. Keep by Default (initially expensive, with reimbursement on data removal)

He said there are many advantages of using rollups; 

![Motivation Rollups](https://dev-to-uploads.s3.amazonaws.com/uploads/articles/ndffa3hliio238kk1okl.jpg)

This includes freedom to experiment, inheriting layer 1 security, the ability to create governance tokens, etc, this allows for easy collaboration and integration of different needs. 

He compared the gas costs of transferring tokens for several existent rollups, such as Arbitrum ZK-Sync, Fuel, etc.

![How Ephemeral Call Data Works](https://dev-to-uploads.s3.amazonaws.com/uploads/articles/a9ckqho995lraeqgye41.jpg)

He explained how the Ephemeral Call Data is implemented by creating a new field in an RSK transaction. He said this field contains other fields and that instead of the ephemeral call data (ecd) being hashed into the transaction, it is being double-hashed. This double hash gives the opportunity to remove the original data without changing the transaction ID. He explained other fields like the `ecdSize`, `ecdHash`, `hasherContractAddress`, `hasherCallGasConsumed`, etc as captured in the image above.

See related links:
- [RSKIP-281](https://github.com/rsksmart/RSKIPs/blob/master/IPs/RSKIP281.md)
- Discuss [RSKIP-281 for Ephemeral Call Data](https://research.rsk.dev/t/ephemeral-calldata-rskip281/241)

He summarized his talk by saying, the ephemeral Calldata reduces the cost of Rollups realistically (compared with the unrealistic reduction in the case of Ethereum), it can be removed by default, or kept by default. It also requires changes on several parts of a consensus protocol, and it competes with other RSKIPs, such as RSKIP-215 (Ephemeral Blockchain).

## Decisions

No decisions were made during the October Community Call.

## Summary

For more details on these, please watch the [recording on Youtube.](https://youtu.be/mdCinpZ7Qcg)

Want to champion an RSKIP? Missed the previous RSK Community Call? Watch the [recording on Youtube](https://youtu.be/lZ0Y4VHvR4Q). Also, leave a comment on [this thread for the next community call](https://research.rsk.dev/t/community-call-november-december-2021/245)!

## Resources

-   [RSK Community Call May, 2021](https://youtu.be/Cl1NWsJrFmI)
-   [RSK Community Call, July, 2021](https://youtu.be/H15kZD15oSg)
-   [RSK Community Call, August 2021](https://youtu.be/lZ0Y4VHvR4Q)
-   [Discussion for next RSK Community Call](https://research.rsk.dev/t/community-call-november-december-2021/245)
-   [RSK Improvement Proposals Repository](https://github.com/rsksmart/RSKIPs) 
-   [RSK Discourse Forum](https://research.rsk.dev/)
-   [RSK Developer Portal](https://developers.rsk.co)  
-   [RSK Community Slack](https://developers.rsk.co)
  
Thanks for reading!