Gaining visibility in IPFS systems

We have been operating an IPFS gateway for the last four years. It started as a research experiment in 2018, providing end-to-end integrity with IPFS. A year later, we made IPFS content faster to fetch. Last year, we announced we were committed to making IPFS gateway part of our product offering. Through this process, we needed to inform our design decisions to know how our setup performed.

To this end, we've developed the IPFS Gateway monitor, an observability tool that runs various IPFS scenarios on a given gateway endpoint. In this post, you'll learn how we use this tool and go over discoveries we made along the way.

Refresher on IPFS

IPFS is a distributed system for storing and accessing files, websites, applications, and data. It's different from a traditional centralized file system in that IPFS is completely distributed. Any participant can join and leave at any time without the loss of overall performance.

However, in order to access any file in IPFS, users cannot just use web browsers. They need to run an IPFS node to access the file from IPFS using its own protocol. IPFS Gateways play the role of enabling users to do this using only Continue reading

Privacy Pass v3: the new privacy bits

In November 2017, we released our implementation of a privacy preserving protocol to let users prove that they are humans without enabling tracking. When you install Privacy Pass’s browser extension, you get tokens when you solve a Cloudflare CAPTCHA which can be used to avoid needing to solve one again... The redeemed token is cryptographically unlinkable to the token originally provided by the server. That is why Privacy Pass is privacy preserving.

In October 2019, Privacy Pass reached another milestone. We released Privacy Pass Extension v2.0 that includes a new service provider (hCaptcha) which provides a way to redeem a token not only with CAPTCHAs in the Cloudflare challenge pages but also hCaptcha CAPTCHAs in any website. When you encounter any hCaptcha CAPTCHA in any website, including the ones not behind Cloudflare, you can redeem a token to pass the CAPTCHA.

We believe Privacy Pass solves an important problem — balancing privacy and security for bot mitigation— but we think there’s more to be done in terms of both the codebase and the protocol. We improved the codebase by redesigning how the service providers interact with the core extension. At the same time, we made progress on the Continue reading