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Cryptocurrencies have had a rough year. Bitcoin has crashed more than 75 percent since its peak, and its competitors are faring no better. Even if the bubble has burst on non-fiat currency, the technology underlying those coins, the blockchain—which offers a way to record and validate transactions without a central authority, such as a bank or government—still excites many speculators outside finance.

In cities, for example, evangelists have promised an array of “blockchain urbanism” innovations. Some are outrageously ambitious: Crypto-entrepreneurs are migrating to marginal zones and developing regions where light regulation and low taxes permit them to build new states and cities in the blockchain’s own image. Others are more modest, applying the blockchain to urban inefficiencies in planning, zoning, building performance, and energy trading.

Blockchain is also backing a new mode of mapping. Crypto-cartographers hope to use it for spatial verification—confirming that things are where they say they are, when they claim to be there. How might this be useful? Well, you could know precisely when an Amazon delivery drone drops a package on your doorstep, at which point the charge would post to your account. No more unscrupulous delivery drivers, and no more contested charges for packages lost in transit. Or when opening a new bank account, you could virtually confirm your permanent address by physically being there during a particular verification period, rather than providing copies of your utility bills. You could also submit a photo of your flooded basement or smashed windshield to your insurance company, supplementing your claim with time- and location-verified documentation. Or, as you pass by your local family-owned coffee shop, the owner could “airdrop” some Bitcoin coupons to your phone, and you could stop by to cash in before the offer expires a half hour later.

These examples are certainly appealing. But the physical world might not be as easy to map as crypto-cartographers believe.


Money was blockchain’s first target, but in theory, any type of agreement that currently requires a middleman could be managed with blockchain technology instead—no lawyer, notary, bookie, or referee needed, as The New Yorker’s Nick Paumgarten puts it. A blockchain-based “smart contract” fulfills itself automatically, when its agreed-upon conditions have been met. The proof-of-location (PoL) protocol uses this approach for spatial verification.

Of course, we already have tools for geographic verification—Google Maps, Foursquare, OpenStreetMap, and the state-backed Global Positioning System (GPS) they rely on. But crypto-cartographers say we can’t always trust them. The commercial maps’ data are proprietary, and their plotted features sometimes fail to reflect rapid changes in real space. Crowdsourced tools such as OpenStreetMap are dogged by problems: insufficient funding, confusing usage policies, the failure to create incentives for contributors, and difficulty with accuracy.

And GPS, some critics say, is poorly suited for use in dense urban environments and indoors, drains cellphone batteries, and is centralized (a big downside for blockchain advocates). According to PoL upstart Foam, “Civil GPS is unencrypted, it has no proof-of-origin or authentication features, and despite dire warnings first raised in 2012, the system remains extremely susceptible to fraud, spoofing, jamming, and cyberattack.”

The cartographer and historian of science Bill Rankin finds some of these critiques a bit overstated. But they partly explain why Foam argues that “no reliable and trusted location verification service” exists, and there are “no established standards for embedded locations, physical addresses, or coordinates in smart contracts.” In the growing PoL space, each new platform comes with its own hardware infrastructure, protocols, economy, and obfuscatory language. Foam plans to create incentives for operators to build low-power, wide-area networks composed of radio beacons that can access the unlicensed radio spectrum. According to the CEO, Ryan John King, “Zone operators on the Foam network are in essence providing comparable work to Bitcoin miners.”

When four or more proximate beacons (Foam calls them “anchors”) form a “zone,” they can synchronize with one another to determine the position of objects. GPS works using the same general method, but it allows only for one-way communication; Foam’s PoL protocol allows users to send messages back to the system, which confirms the location via “verifiers” and saves it on the blockchain, King told me. What’s more, the Foam network is pretty hard to jam, and it requires less power than GPS does.

Foam’s protocol is open source. But cartographers have to purchase tokens that entitle them to contribute to it. Zone operators both stake and receive tokens as they perform their geolocative labors. The company hopes that this incentive system, which is not found in other volunteer crowdsourced projects, will help extend the network’s geographic coverage.

The protocol promotes other rewards, too. For a fee, anchors can also offer location services that use smart contracts to link a location on the blockchain to an address—a geohash—on the physical map. That’s how services including package tracking, address verification, and contract enforcement might work.

Location is meant to be commercialized: The platforms hope to “foster an ecosystem of applications built on top of a verified location standard,” as Foam puts it. The whole ecosystem, rather than some centralized authority, gets to determine what’s featured on the map. Contributors can stake their Foam tokens to create lists of points of interest (POIs), such as coffee shops with Wi-Fi, the best dog parks, urban landmarks, or government facilities. Other token holders can then vote on those lists; up-votes increase the value of the list and the value of the list creator’s tokens. Down-votes indicate that other token holders presume that a nominated POI will degrade the quality of a list.

Atop this infrastructure, Foam provides an interface, which it bills as “a cross between a Bloomberg trading terminal and Google Maps.” The dashboard allows users to interact with and act on all those smart contracts, facilitating an array of applications—from autonomous-vehicle tracking, to supply-chain management, to location-based games such as Pokémon Go. A Foam competitor, XYO Network, proposes that PoL could also help government agencies and police forces track regulated firearms, to make sure that they’re always in the hands of the agents authorized to handle them. I asked King whether or how they plan to discourage particular uses, such as surveillance and predatory marketing. He told me that “governance is built into the protocol” (unlike with GPS). Foam requires users to make a minimum deposit to participate; putting one’s own tokens up as collateral, King said, serves as an “anti-spam mechanism.” The voting procedure also provides checks and balances.

King explained that Foam’s is the only PoL project “providing full-stack location services,” including location and coding standards and the visualizer. “It’s important to start from scratch,” he said, to start a “whole new infrastructure,” to make location “holistic.”


What makes a “quality” list of places in the world? Foam claims that it focuses on “objective” spatial information, yet it seems to see spatial value in “economic or reputational terms.” That could lead users to stake their tokens to map readily verifiable, predictable features and high-quality neighborhoods and facilities (that is, those with a strong reputation for good schools, low crime, and high property values). Even so, users can also use their tokens to “signal” where location services are needed and to inspire growth in underserved areas. A bet on an up-and-coming area determines users’ “spatial-mining rewards”—the bounty doled out, in this case, for extending the map to underrepresented regions.

Signaling could become a means for crypto-real-estate speculation. That could have material effects—perhaps even gentrification and displacement—in real life. Yet King proposes that signaling could also be a “catalyst for projects for public good”—new green spaces or green development, for instance—and could enable cartographers to “attribute community value to places.”

Foam presents its crypto-mapping as an extension of mapping’s legacy, calling its users “contextualized successors to the work of cartographers throughout history that maintained geographic data about everything from topography to dense urban streets.” At the same time, the company sees itself as an economic and political engine, “granting control over the registries of POI to locally based markets and community forces.”

It’s hoping to inspire new urban services, local engagement, and increased efficiency. But not all “community forces” are positive; they also include NIMBY-ism and entrenched patterns of racism, classism, and other biases. Even social-entrepreneurial crypto-cartographers ostensibly committed to the public good could still plot and vote for points in accordance with their privileged (and, given that we’re talking about the blockchain, probably young male) perspectives and blind prejudices. Voting for points of interest hardly guarantees that they will serve the public well.

Foam also builds on the biases of its precursors, including GPS. As Rankin explains, the creators of GPS saw it as a utility that turned location into “a commodity available in much the same way as electricity or water.” For Rankin, that design has political implications: It “substitutes a locally available grid of geographic coordinates for other kinds of local knowledge,” such as folklore, vernacular histories, or habitual experience, he says. In so doing, GPS “encourages intervention without long-term commitment.” PoL could similarly incentivize location miners to find “collective value in the growth of the network,” as King proposed to me, framing growth and network effects as civic values. Still, crypto-cartographers could experience space through a dashboard, engaging with it via speculation, rather than with an abiding sense of local, on-the-ground responsibility.

What’s more, some things just don’t want to be “verified” or “divined.” Problems sometime arise when working with digital representations of physical assets such as land parcels. Property boundaries, historically marked by degradable and movable things—stakes and streams, fence posts and handshakes—are often contested, and land areas are sometimes miscalculated because of accumulated historical errors in measurement. Overall, there is far more fluidity in matters of physical boundaries and access than blockchain allows. Who knows how spaces such as informal infrastructures, indigenous terrains, and the leftover spaces that shelter the marginalized would fare in a crypto-map? Such spatial negotiations hardly seem to lend themselves to “objective” mapping and token-based votes. If the crypto-cartographers have their way, those communities could be down-voted into oblivion.

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