Footnote

Footnote is an experimental Handshake layer two protocol for storing, synchronizing, and addressing small amounts of data. Its purpose is to create a global, decentralized, and permissionless data commons that allows everyone to store and retrieve data from any node on the Footnote network.

Abstract and Motivation

The Internet today favors a client-server model. Clients - who function like customers - request or upload data to servers - who function like vast warehouses of data under the control of the companies that own them. For most applications, this works well. There's no need nor ability for one's browser to know everything about every other Facebook user, the same way there's no need for people to stockpile every item at their local Costco.

The client-server model, however, has its tradeoffs. Take Twitter: whenever a user sends a Tweet, that Tweet becomes the property of Twitter. Similarly, it is not Twitter's users that decide what appears on their news feeds but rather Twitter itself. Oftentimes this is done for scalability or content moderation reasons. Twitter needs to serve Tweets to over three hundred million people, so unfettered access to their firehose would be technically infeasible. Similarly, while ads help Twitter pay for hosting, not all content is advertiser-friendly. In sum, clients sacrifice the sovereignty of their data, as well as their ability to query other people's data, in return for scale and convenience.

Footnote exists to serve data that may not fit the existing client-server mold. Rather than building another warehouse, Footnote creates an open plaza that anyone can observe or contribute to. Every node on the Footnote network serves everyone else's data. There's no DHT querying, sharding, or partitioning: every node is equal. This allows developers to build rich, interconnected applications on top of Footnote that leverage a persistent, global view of all content on the network. Imagine a version of the Internet built to be "locked open"; every server stores every website's content by default. While this might sound redundant at first, consider the decentralization-preserving protective effects (i.e. equal access) if the web we know today was built on top of it. Users could query data locally by default, and be able to choose which filters or and moderation to apply (or even to supplement with centralized infrastructure). This is what Footnote aims to enable.

Creating such a global view would be impossible without constraints. This is because without constraints, as the network grows, resource and administration requirements increase. This effect prices out smaller players. Footnote's constraints are (i) bounded storage available to (ii) a bounded number of names. For the former, Footnote identifies users by their Handshake name, allowing each user to store a maximum of 1 mebibyte on the network. For the latter, Handshake itself imposes a maximum global renewal limit through its on-chain transaction throughput: around 50-100 million names can exist on Footnote. Taken together, a Footnote node's maximum storage requirement is on the order of tens of terabytes. As the cost of storage trends downwards, the resources required to run a Footnote node should trend downwards as well, even as the network itself grows in usage. In sum, Footnote leverages Handshake's Sybil-resistance properties and constraints to create the first durably decentralized public data commons.

Protocol Specification

At this time, there is no canonical specification. Early in the design process, a loose protocol specification was previously defined through a series of Protocol Improvement Proposals (PIPs), which can be found here. They are made available for accuracy and to provide context. Please see the other document in this repository, ideas.md for examples of potential protocol improvements.

Links

Protocol Implementations

Language	Project	Notes
Go	fnd	Reference Implementation, by @mslipper

Client Libraries