# Introduction to Unirep: ZK data system - Vivian, Ethereum Foundation

###### tags: `2023`, `DAY2`, `ZK`
{%hackmd @ethtaipei/ByQLufgQ2 %}

> Share your thoughts from here

# Status Quo
many platform: airbXb, boXking.com, distributed reputation

# Protocol

`epoch key = hash(user privK, attester id, epoch, nonce)`

built on top of semaphore

user can be forced to generate epoch key when renting (Airbnb example)

# use case
1. reputation from github:
a possible data: increase star, decrease follower, etc..

2. forum
3. c2c platform

# QA
is sum data field custom to attester?
sum data field multiplied by factor?
for example, in some case cleaness is more important