Towards Validator Privacy and Private Information Retrieval / Dr. Marina Steinkirch

Transcript

and thank you for coming to my talk I'm Dr Marina Von steinkers also known as Mia or bite girl and the doctor comes from a PhD and competition was to physics from the University of New York in the next 15 minutes we talk about the Fallen first I'm gonna introduce myself so you have an idea of my background and why I'm interested in these problems and perhaps um you're interested as well and we know you can join us or collaborate in some capacity then I give you a summary about my research at the Privacy scaling solutions group at ethereal foundation and after that I will wish you a great weekend I hope you have a lot of fun in

Prague The Alchemist City so let's begin so this is the tldr of my story I was born in Brazil and since our early age six or seven years old I started playing with computers my parents didn't have much money so I would sneak out at my Uncle uncle's computer when he was not home later on my mom was able to get me a painting too and then the story began I started coding playing with several Linux distributions within my teens but I was also very keen on physics and

math even though I went to Public Schools my entire life in Brazil um I started my ass off and I was able to be accept at this top program the engineering program at University of Sao Paulo the past University of Brazil um right after that I got a full scholarship for PhD in Stony Brook and in my last year a college in Brazil I also got the summer scholarship to spend a summer research in a NASA I go there standard and wash them Washington DC when I moved to the US by myself

I better the hope of finding a better life that I had in Brazil and that was right after my dad was murdered in Brazil in New York I took all the classes they could in theoretical physics some math grad courses and a lot of computer science supports I wrote several papers I wrote uh academic books on group Theory quantity Theory and Quantum information I researched and published papers and was all in the loss on National Lab and the Brookhaven National Labs and I also wrote the book in Python algorithms and data structures I got really into code machine learning

hacking so I decided to turn down uh for a postdoc at the Los Angeles to get the job as a back-end engineer at the security team at Elk in San Francisco that was when my career as engineer started right after that I worked at Apple in the Korea core OS team and then after a year in Cupertino I became a normal working at the security and fraud team at Etsy at some point after that I realized I need to find some personal answers regarding the meaning of life or myself or my existence so I took a little Gap

time to travel the world as a nomad and they learned to Surf I went to place awesome places to snowboard I took a lot of pictures and I made some abstract drowning videos of the places I I visit even though the concept of home was always diffuse for me being officially homeless was mostly relating and changing it forever when it was back to my passion of being a scientist and an engineer I knew I could only work with purpose I would choose which work wisely I joined top five during the pandemic

because I admired Toby and the impact that they had in the world um with Shopify anyone could have their own business and if my dad had that those resources in Brazil when I was growing up our lives would probably be different at Shopify I was one of the founders of the blockchain team and I became informally they had a blockchain engineer helping to oversee energy drops to some big partners and educating everyone regarding blockchains a well-regarded position at the end of 2021

should go to the wild I started this decentralization in self-subthering movements that we are creating and I wanted to be part of it even though if the man to go back to square zero since then I worked at the field house I developed an MAV soldiers I learned a smart contract security at a modified I trained training defiations of reinforcement learning I spoke my own personal infrastructure for projects I care about and mostly recently I joined the great Community uh at the ethereum foundation

with the Privacy scaling solutions group now at EF I'm leading two projects one is the validator Privacy research which I will be talking a little bit in the next minutes and the order is on private information retrieval uh the research of a protocol uh with cryptographic Primitives that allow user to retrieve information from database from server without revealing what is what is they are trying to uh retrieve even though it's fascinating I won't be

able to discuss PIR in this talk uh but I invite you to follow my work and follow the PSE group from future outreachness in the subjects now let's uh take the next means to actually talk about the research on validator privacy thank you and let's move on to my presentation hi in this presentation I will give you the toldr of our research on validated privacy at the interior Foundation for that event of the merch on September

of last year the theory Network moved away from its original proof of world concerns mechanism to the implementation of proof of stake consequently the chain was split into execution layer represented by this equation client in the vehicle node in the constants layer represented by a constant's client in the validator node however even though both clients are logically separate they can still be around the same machine in network address one of the most significant consequences of this update was highlighting the role of validatorious takers there are over 600k active validators in the tier Network in this the time of this writing holding

over 90 million stake each why is taking rewards have significantly shifted to Enterprise Solutions such as validator as a service lsds staking posts and centralized exchanges solid stickers contributions are essential to help preserve the solvent in the decentralization ethos of the ethereum project the ethereum 2.0 will be accounting a legend of accounts that coordinates how new blocks are created and validated in the chain provides the heartbeat to a tourist consensus and introduces the Network's consensus logic and block gossip protocol

why are the validator client is responsible for credentials and consensus masses bringing a network to a conferences in the finalized state this efficient client is responsible for participating in the blockchain P2P Network by subscribing and Publishing message to gossip Pub sub gospel soap topics and storing blockchain data in this new paradigm every 12 seconds a validator is randomly chosen to propose a block through the new slot digital number of validators is split up into committees in one or more individual committees are responsible for a testing to each slot one validator from the committee is

chosen to be the aggregator while it was the other 127 validators are just a testing after each Epoch defined by 32 slots or 6.4 minutes the valid areas are mixed and merged in the new committees the POS validation scheme requires validated public keys on the background chain to be known to everyone ahead of time the validator ordering for slots is known by the network within the epoch in other words block proposals from an Epoch are revealed in that events why IP address revealing at this execution layer isn't isn't that

inevitable attestation in blocks from validator nodes can leak information that allows an attacker to associate a validator ID with an IP address unless operators are using sophisticated measures in addition even though a validator can submit the consensus message to multiple vehicle nodes there is few risks of metadata analysis attacks including the size of the message frequency of broadcasting message the timing of the message joining you leaving subinet events in packet or data science difference between attestation and other messages if you divided are these or wallet

addresses on the constances layers can be linked to the background IP address the validator operator could be the anonymous anonymize it permitting consequences such as destabilizing the network denial of service of block producers through things such as validator sniping in solid stickers disenfranchisement due to government government sanctions for example of fact or even worrying by ordering of having their device stolen a popular scenario discussed among resources is of a attacker watching the vehicle chain Network by running a node modified to gather the IP address of all

connected peers when they broadcast at the stations the attacker can then create a database of ips and public keys and with this information they could take the value of line when it becomes a block proposal so soft skilled right the attacker controls the next validator proposal taking all the MEP opportunities for example in summary Nova diversary should be able to link personal in the identifiable information through staking activities so we care about or before skating the connection between a validator and its IP address for instance stickers of A

non-key USC wallet should have plausibility and ability in controlling a validator that proposed or attested to a particular block for example or for fat restrictions how can a validator assign a produce message be disassociated from the vehicle node it's originated like everything is secured resolutions are found at main layers a comprehensive solution would include a mechanism of validator proposal elections that protects daily in The Institute of the next proposal a network anonymity mechanism that doesn't mess if the current block

proposing latency zero knowledgeable mechanisms like ziki snarks from message credibility and spam protection even to and even to verify the legislative legitimacy of a validator for instance prove that they are unique and valid without revealing more information ethereum biod of privacy is an active area of research and discussion in the definitive answers too needs to be defined in addition while some improvements might be shipped in protocol in the subsequent ethereal per dates we are also considering implementing a consensus client obtain

of obfuscation if you are interested to learn more I invite you to look at this paper I will be published publishing in the next days where I'm summarizing the research material validator of privacy over the last years this document intends to be overview of the main efforts from many talented researchers in this last years and some discussion of what could be next here's his sneak peek of the paper finally for updates regarding this research and more I invite you to follow me on my GitHub or mirror for General

scaling and private research iaf mostly focus on the ziki applications I suggest you to follow the PSC group either GitHub mirror Twitter finally if you're a particularly interested in this research feel free to leave any comment below in this case I'll take a look later on and I might respond accordingly thank you so much for listening to this presentation enjoy the conference bye [Music]