FOAM is a Proof of Location technology for applications needing secure location services. It enables a handshake between the location service providers (FOAM network) and the user, proving the user’s location. Terrestrial radios and time-of-flight algorithms are used to perform localizations, and digital signatures ensure the location data cannot be spoofed. The system is completely independent of satellite-based location services like GPS.

Today we are excited to share more information on the work going into FOAM and the Proof of Location protocol. Recently, the Trust Zone Beta Program has successfully completed with testing in many geographies. Since then we have been building onchain contracts for end to end Proof of Location: the FOAM MVP. As shared in our previous post, this work is Built on the Optimism OP Stack 🔴

Announcing the FOAM MVP! 🏆

Open Proof of Location is no longer an unsolved problem. As the next step in our roadmap, the FOAM MVP is the first full-stack demonstration of an open, Proof of Location network. From radio hardware and firmware to user interfaces and blockchain smart contracts, the FOAM MVP proves that fault-tolerant location data is finally here, and demonstrates its importance in onchain and off-chain use-cases.

The end user output of FOAM’s Proof of Location system is a “Presence Claim”, a location proof represented as an onchain NFT (ERC-721). Users can opt to share their Presence Claims with other applications or to trigger smart contracts with location data. You can think of a Presence Claim as a digital certificate proving the presence of someone or something at a specific location and time. The FOAM MVP demonstrates the creation and usage of Presence Claims.

Tell me more…

The first stage of the MVP will focus on the end-to-end process of minting a Presence Claim and viewing it in a web3 wallet. We call this our MVP 1.0, and and it is currently in the final stages of development. The MVP ties together and consists of the following key components, showcasing the minimum viable tech stack and network required for Proof of Location:

• Zone Anchors: build-it-yourself LoRa radios running custom software-defined radio firmware

• Zones: Trust Zones in FOAM Physical Testnet, online since the Trust Zone Beta Program

• Mobile Node: hand-held radio connected to web3 wallet over BLE on mobile phone, for interacting with Zones over radio to request Presence Claims

• Hostel: the front-end UI for managing Zones and requesting, minting and viewing Presence Claims

• Onchain Testnet & Contracts: testnet with minimal contracts for registering Zones, validating localization data, minting Presence Claims, Zone staked and fees earned

The FOAM MVP adds two critical elements to our stack, completing a minimal viable version of Proof of Location: onchain contracts and a UI for requesting and minting Presence Claims.

MVP 2.0 will demonstrate the power of Presence Claims by featuring their use in selected web3 and other smart contract applications. We will build the first demo application ourselves (hint: an onchain geospatial game 👀), and also involve other pilot use-case demonstrations. If you are a project, company, or dev interested in onchain location data or Proof of Location more broadly, please reach out!

The FOAM MVP will be publicized for the community in the form of written blog posts, in-person presentations and/or webcasts. Additionally existing FOAM Zones will be upgraded to run onchain as part of the MVP. As we then migrate our Proof of Location contracts to a public OP testnet, we may share access to our Hostel web-app and make the MVP Presence Claim functionality available for users and developers alike to tinker with. The intended audience of the MVP is you - the FOAM community, made up of future users, Zone Operators, past and future stakeholders, and projects waiting for trustworthy onchain location data. So along the way, we will be prioritizing keeping you as informed as possible. Our next post will focus more detail on the smart contracts themselves and upcoming demos.

Get Involved!

Projects and Devs - Please reach out if you are a project, company, or developer interested in using or building on FOAM’s Proof of Location system. You can email coleman@foam.space.

Zone Operators - We continue our open call for new Trust Zones via our application waitlist, which we check regularly. If you meet the core requirements listed below for participating in our network at this stage as a Zone Operator, please reach out via our waitlist or by emailing coleman@foam.space with proposed location coordinates or addresses for your Zone.

1. A minimum of four outdoors locations, where radios (12” x 10” x 5.5”) and antennas* (~12-36”) can be installed

2. Visual line-of-sight between at least four locations

3. Distance of approximately 100m-2000m between each location

4. Stable power supply,** such as GFCI or power-over-ethernet (PoE+)

5. Internet available (e.g. cellular LTE, WiFi or Ethernet)

*Radios use open, unlicensed Industrial, Scientific, Medical (ISM) band of the radio spectrum, to send and receive transmissions. Hardware uses LoRa, a low-power, long-range radio technology.

**Supply voltage of at least 12V required with max current ~600mA. Average power consumption is 0.15 kWh per day.