GeoSatoshi: A Blockchain for Geospatial Data
- 发布日期: 2018 年 4 月 2 日 Mark Seibel，Mark Seibel - email@example.com
Abstract. A purely peer-to-peer open source ecosystem allowing for the aggregation, storage and distribution of geospatial data. Blockchain technology provides part of the solution, but the main benefits of this system are lost if a trusted third party is required to administer or control the system. Proposed for the geospatial community, is a digital commerce system built on blockchain technology, which encourages and promotes the creation of high quality geospatial data. To incentivize high quality data, authors and reviewers are rewarded with the ecosystem’s GeoSatoshi coin as currency. Using blockchain technology solves several geospatial data problems: accessibility, centralized ownership and global affordability. Viewing the data is free to promote open access, but downloading features requires the GeoSatoshi coin as currency. A feature of anonymity is proposed to eliminate coercive forces from intimidating users and to promote data gathering in unorthodox, yet ethical, ways. By way of the geoblockchain, data is not sent; it is accessed with a key. The proposed system uses digital coins to incentivize organizations to publish their proprietary geospatial data to benefit the geospatial community at large.
Geospatial data contains keys to unlock solutions to the environmental problems our world faces. It is paramount that this data be searchable and made accessible to scientists and engineers around the globe. One clear problem is that geospatial data has found its way into many corners of the Internet, in both public and private space. Data continues to be built at an organizational level, without an overarching technology to aggregate the data and connect users.
Modern efforts to solve the data fragmentation problem work towards aggregating geospatial data into centralized spatial databases. Organizations invest capital in people, hardware and software, and thus the resulting system and data are only available internally to the investing organization. This capitalist behavior keeps valuable and necessary geospatial data away from the larger geospatial community. While enterprise spatial databases solve the data aggregation problem for organizations, these efforts fail the larger goal of allowing open access for the global geospatial community.
A system is needed to aggregate and distribute high-quality geospatial data to the community based on cryptographic proof of trust, without the need for a trusted party to centralize and own data. The project is expected to grow with rapidity, given that there are decades of publicly available datasets ready to store in the blockchain. More than a transaction system, an ecosystem is proposed to create a place for the geospatial community to exchange and create quality data on a decentralized and scalable public storage system.
2. Ecosystem for GIS Users
Proposed is a trustless ecosystem, with no central authority, that fosters a community for users to interact with each other based on cryptographic trust. Requests can be submitted to the community to build geospatial data in exchange for GeoSatoshi coin. This creates a decentralized and secure place to conduct an open exchange of coins for geospatial data. The proposed built-in, two layer quality control mechanism enforces data integrity on the blockchain. The use of the GeoSatoshi coin is also designed to incentivize organizations to sell their proprietary data to the community through the blockchain.
3. Geospatial Features
The primary asset in the geoblockchain is the geospatial feature. We define a geospatial feature as a point, line or polygon having related attributes and values. The GeoJSON format is the proposed data format for storage on the blockchain. Features that belong to a GIS layer will use attribute values to associate the feature with the layer. Topological information is proposed to be stored with each feature, but topology will be enforced at the application level. Transacting at the feature level simplifies transactions and data sharing between users in the community. Features can be sent to users through the blockchain, without physically transmitting large data through archaic mechanisms like email.
We define an electronic coin as a result of cryptographic work to secure transactions (Nakamoto, 2). Transactions occur at the feature level and require the GeoSatoshi coin. The blockchain solves the problem of double spending GeoSatoshi coins and double selling geospatial features. The decentralized nature of the blockchain provides no central authority for feature transactions. Transacting with features on the blockchain is proposed through a software application that functions as the project wallet and data exchanger.
Data submitted to the blockchain must be of the highest quality or the project will fail. In order to pursue quality, the project proposes a two-layer quality control system. The proposed system allows the community to help strengthen its own geoblockchain by participating in the enforcement of quality data. This proposition allows community members to directly add value to their coin by enforcing high-quality standards on data submissions to the blockchain.
Downloading a geospatial feature from the blockchain is a transaction requiring a GeoSatoshi coin. Uploading data to the blockchain is proposed through a two-step verification process. First, created data is submitted to a level 1 data pool. Then, another user of the system, who may or may not be known to the data creator, can peer review the data for level 1 approval. Chance may be introduced if the data creator does not have a peer selected to review their work. Approved level 1 data is submitted to the level 2 pool, where a randomly selected user is chosen for final quality control. Chance is the proposed measure to add spice to the ecosystem as well as anti-conspiracy protection for community users. Random user selections in the network are designed to oppose attackers from conspiring to game the system by creating and approving poor quality work for coin or the joy of destroying the project with erroneous data.
Transaction anonymity is a proposed option in the ecosystem to protect users. Users who review data for final submission cannot have anonymity because they are responsible for triggering payment to the user who created their data, the peer reviewer and to themselves. The system can be gamed if anonymous poor-quality work is being created and submitted for other anonymous users to approve for coin payment.
5. Timestamp Server, Proof-of-Work and Network
“The timestamp proves that the data must have existed at that [published broadcast] time, obviously, in order to get the hash. Each timestamp includes the previous timestamp in its hash, forming a chain, with each additional timestamp reinforcing the ones before it.” (Nakamoto, 2). This process builds the blockchain by locking blocks together with cryptographic hashes.
A distributed timestamp server can be defeated if an attacker amasses enough computing power to make the network follow the attacker’s chain rather than the honest one. “To implement a distributed timestamp server on a peer-to-peer basis, we will need to use a proof-of-work system” (Nakamoto, 3).
The proof-of-work system keeps the nodes honest and cleverly defeats attackers. “If a majority of CPU power is controlled by honest nodes, the honest chain will grow the fastest and outpace any competing chains. To modify a past block, an attacker would have to redo the proof-of-work of the block and all blocks after it and then catch up with and surpass the work of the honest nodes.” As shown in Nakamoto’s calculations (Nakamoto, 6-7) the probability of an attacker creating an alternate chain of dishonest transactions grows with exponential difficulty.
Proposed is an incentive system to reward the user community for quality work and to reward organizations for submitting their proprietary data to the blockchain for the user community to access. For the community, the system proposes a digital coin-based reward system for submitting quality geospatial features to the blockchain. The reward structure is weighted such that the creator, first level reviewer and final reviewer get 60%, 15% and 25% of the reward respectively. The reward proposition incentivizes private industry to publish their proprietary data to the blockchain in exchange for coin, thereby exposing more private data to the geospatial community.
Proof-of-work is the method to secure transactions and build the blockchain and generate community coins through GPU mining. GPU mining is the proposed proof-of-work, given that users of geospatial software typically use high-end workstations and graphics cards. This situation creates a perfect matchup for users to use their GPUs for blockchain proof-of-work. GPU mining is proposed over ASIC mining to allow more community members to be involved while minimizing user’s capital expenses.
These two proposed incentive methods provide a solution for users to earn coin without investing a lot of monetary capital. The incentives are designed to be fair to all members of the community regardless of their socioeconomic status. The proposed system will not solve the data inaccessibility problem if users cannot afford to monetarily access the data. If at any point the project is found to be restricting data from the community, the project should be redesigned or abandoned as the main purpose of the project is to put geospatial data in the hands of those who can improve lives or our planet.
7. Organizational Node Hosting
Organizations often have GIS Professionals clustered geographically, with GIS users spread out globally. Enterprise configurations for GIS typically centralize data in a spatial database for client software to access. Historically, organizations have invested a lot of capital to build and acquire geospatial data. Organizations, both public and private, play an enormous role in the development of geospatial data. Organizations should be seen as an ally to the project.
When an organization hosts a node, they are a peer node on the network. Organizations have no authority over the system and the only control they have is turning the node on or off. If they misbehave, the community can exclude the node. Organizations provide a benefit to the community by providing resources to strengthen the network through the node they host.
The benefit organizations receive is faster access to high-quality data without the expense of maintaining a data server. It can take a long time to download geographic data because of their potential enormous size. Local node hosting can be extremely beneficial to organizations in parts of the globe with slow Internet access.
8. Simplified Payment Verification, Combining and Splitting Value, Privacy & Hostile Takeovers
The proposed ecosystem uses the same features from Nakamoto’s success: simplified payment verification, combining and splitting value and privacy. Simplified payment verification is applicable for checking the chain without running a full node (Nakamoto, 5). It is achieved through the use of headers. Rather than making the system handle every cent in a transfer, value can be split and combined (Nakamoto, 5). Privacy works by allowing everyone to see every transaction, but not know who is attached to the address in the transaction (Nakamoto, 6). The proposed ecosystem is intended to build a community, so privacy should only be used where users need to protect themselves. Nakamoto’s white paper calculates the odds of an attacker taking over the network using the proposed infrastructure (Nakamoto, 5-8). The best an attacker can do is take over the network. This would require the attacker to generate an alternate chain faster than the honest chain (Nakamoto, 6).
To move geospatial data storage to the future, a decentralized, secure, community-driven global geospatial data storage system is proposed. Centralized spatial databases have served the community well and will still play a role in the near future. Blockchain technology can scale geospatial storage globally and securely, with no central authority. Blockchain technology solves many geospatatial storage problems: data aggregation, public storage and access, private/public access toggle, feature version tracking, transmitting data to users, transparency and capital expense for special data storage and backups.
Embedded in this ecosystem is the proposition of a geospatial data exchange, with the primary beneficiary being the users of the community. The system proposes to provide a mechanism where members can use GeoSatoshi coin to have community members build requested data. The GeoSatoshi coin can also be used as incentive to encourage organizations to publish their data proprietary data to the geoblockchain for community use. A two-layer quality control system is proposed to promote high-quality in the geoblockchain.
The GIS community has a very impactful presence in the open source community. There are a large number of high quality open source software projects that work with geospatial data. GIS software is available for free across the globe, but geospatial data can be hard to locate or broker. Blockchain is a current technology that can give the GIS community a step into the future.
Bitcoin: A Peer-to-Peer Electronic Cash System; Satoshi Nakamoto