diff --git a/FRPs/FRP_proposal b/FRPs/FRP_proposal new file mode 100644 index 0000000..a25e2ab --- /dev/null +++ b/FRPs/FRP_proposal @@ -0,0 +1,142 @@ +--- +id: +title: SoK: Proposer-Builder Separation and Beyond +team: Oriol SAGUILLO, Prerna AROTE, Lucianna KIFFER (IMDEA Networks Institute) +created: +--- + +## Background and Problem Statement + +Proposer–Builder Separation (PBS) [7][11][5], together with MEV-Boost, represents the first widely adopted approach for decoupling block construction from +block proposal in Ethereum. These mechanisms have enabled a more efficient and competitive market for block building and MEV extraction [2][28][1]. However, +their current realization relies predominantly on off-chain relayers, introducing non-trivial trust assumptions and creating centralization pressures +within the block production pipeline [27][11][10]. + +In response to these limitations, a broad spectrum of alternative designs and protocol-level enhancements has been proposed. These include (but are +not limited to): +• Enshrined PBS[20][14] +• Encrypted and Privacy-preserving block building [13][23][12] +• MEV burn mechanisms [8] +• Execution tickets [4], +• Execution auctions [3], +• Inclusion lists (FOCIL, AUCIL, COMIS, etc.) [26][24][25], +• Cross-domain PBS architectures [19][18][16] + +Each class of design targets distinct challenges of the existing PBS model, such as reducing relayer dependence, +mitigating censorship and liveness risks, improving incentive alignment across participants, and strengthening security guarantees for validators and order-flow +providers. + +However, discussions of these designs, including their security assumptions and trade-offs are fragmented across blog posts, research articles, and forum +discussions. As a result, there is no single, comprehensive resource that systematically compares these approaches or clearly outlines their shared objectives, +design trade-offs, and remaining open challenges. + +The goal of this project is to compile and systematize existing PBS-related +designs across different layers of the blockchain protocol. The project will identify and categorize the desired properties of proposer–builder separation mech- +anisms, analyze known and potential attack vectors— Sandwich attack, Frontrunning attack [7][9], Back-running attack[21], Free-option problem[15], Timing +game[22], Equivocation attacks [17], Bribery attack[6], etc. , and highlight open research questions. By providing a unified framework for understanding current +proposals and their limitations across both industry and academia, this work aims to serve as a reference for researchers, protocol designers, and the broader +blockchain community. + +## Plan and Deliverables + +The study will proceed in the following steps: + +• Compile and review existing literature on Proposer–Builder Separation (PBS), including current implementations and proposed alternative de- +signs related to any step in the workflow from transaction submission to block validation. +• Formalize the key properties required for a secure, efficient, and decentralized block-building system. +• Analyze known and potential attack vectors that obstruct the realization of these properties, and discuss their implications for different PBS de- +signs. +• Synthesize the above analysis into a unified taxonomy of PBS design trade-offs, highlighting open problems and directions for future research + +## References + +[1] Hayden Adams, Brad Bachu, Alex Nezlobin, Sara Reynolds, Dan Robinson, +Mark Toda, Xin Wan, Zach Wong, and Ciamac Moallemi. 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