# PROF: Protected Order Flow in a Profit-Seeking World

**Authors:** Kushal Babel, Nerla Jean-Louis, Yan Ji, Ujval Misra, Mahimna Kelkar, Kosala Yapa Mudiyanselage, Andrew Miller, Ari Juels  
**arXiv:** [2408.02303](https://arxiv.org/abs/2408.02303)  
**Date:** 2024-08-05  
**Summary page:** https://www.summarizepaper.com/en/paper/2408.02303v1/

## Key points

- In the world of decentralized finance (DeFi), users face risks from malicious actions like maximal-extractable value (MEV) that manipulate transaction orders for profit.
- A new system called PROF (PRotected Order Flow) has been introduced to combat MEV in existing Proposer-Builder Separation (PBS) systems.
- PROF enforces a specific order on transactions to prevent manipulation and ensures profitability for block producers, maintaining stability in the DeFi ecosystem.
- PROF is backward compatible with current and future PBS designs and can integrate with various transaction ordering algorithms.
- Despite its robust security measures, PROF operates efficiently with low latency and no additional trust assumptions among PBS entities.
- Thorough analysis shows high inclusion likelihood for PROF transactions, concrete latency numbers, and how it safeguards users against MEV exploitation in DeFi.

## Summary

In the world of decentralized finance (DeFi), users are constantly at risk of falling victim to adversarial actions that manipulate transaction orders to extract value from unsuspecting individuals. This malicious practice, known as maximal-extractable value (MEV), not only impacts individual outcomes but also threatens the overall stability of the DeFi ecosystem. To combat this growing concern, a new system called PROF (PRotected Order Flow) has been introduced. PROF is specifically designed to mitigate harmful forms of MEV within existing Proposer-Builder Separation (PBS) systems. The system operates on two key principles: first, it enforces a specific order on a bundle of privately input transactions all the way through to block production, effectively preventing any manipulation of transaction order. Second, PROF ensures that these bundles are profitable for block producers, guaranteeing their timely inclusion in blocks. One notable feature of PROF is its backward compatibility with both current and future PBS designs. Additionally, it can seamlessly integrate with any desired algorithm for ordering transactions within a PROF bundle, such as first-come-first-serve or fee-based systems. Despite its robust security measures, PROF executes efficiently with low latency and requires no additional trust assumptions among PBS entities. The incentive structure and utility of PROF have been thoroughly analyzed both quantitatively and qualitatively compared to existing solutions. The system demonstrates high inclusion likelihood for PROF transactions and provides concrete latency numbers through its end-to-end implementation. Authored by Kushal Babel, Nerla Jean-Louis, Yan Ji, Ujval Misra, Mahimna Kelkar, Kosala Yapa Mudiyanselage,
Andrew Miller,and Ari Juels; this comprehensive study on PROF sheds light on how protected order flow can navigate the profit-seeking world of DeFi while safeguarding users against MEV exploitation.