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January 2020
PHOTOGRAMMETRIC ENGINEERING & REMOTE SENSING
NTRODUCTION
Blockchain technology is one of today’s most popular
technologies. Blockchain, which we can define as a
decentralized distributed database system, techni-
cally combines all records in the block structure and
unites them as an integral chain that stores them
from the first block. The main advantage of Block-
chain technology is that the information obtained is
precise and cannot be changed.
Blockchain technology enables clients and provid-
ers to operate directly with each other without the
need for authentication by a third party. All transac-
tions are held in a distributed database using cryp-
tography to ensure that the transaction between the
client and the provider can be done safely. To make chang-
es to this distribution structure, the corresponding change
must be saved on all computers in the system. In order for a
cyberattack to be successful, the corrupted data must be ver-
ified by at least 50% of the users within the whole network,
which makes the success of an attack almost impossible. Ad-
vantages such as more security, agentless processing, and
transparency in data tracking make Blockchain technology
attractive for geographical information systems.
Today we see the popularity of Blockchain technology in
financial transactions such as Bitcoin. However, Blockchain
is a system that can be programmed to record the value of al-
most everything, not just financial transactions. Blockchain
technology is an emerging technology that meets the need of
buyers and sellers to exchange data in a digital environment
resistant to cyberattacks without the need of any third-party
intermediaries.
Since 2015, applications have been developed in many
areas using Blockchain technology including geographical
information systems. Yli-Huumo argues that Blockchain ap-
plications are not limited to cryptocurrency applications and
Blockchain will provide diversity and knowledge to work
in various areas of smart ownership (Yli-Huumo, Ko, Choi,
Park, & Smolander, 2016). This arena is one of the signif-
icant areas that can use Blockchain technology. There are
valuable applications of GIS-Blockchain usage in land reg-
istration (currently used in Brazil, Honduras and Sweden),
detection of border violations, and food tracking systems. In
this paper, the use of Blockchain infrastructure in geograph-
ical information systems will be examined.
I
SMART CONTRACTS
Bitcoin crypto currency has obscured Blockchain tech-
nology due to its popularity in the financial field. How-
ever, Bitcoin is actually an application developed using
Blockchain technology and has gained much more stat-
ure than Blockchain technology Many people who do not
know Blockchain technology are quite knowledgeable
about Bitcoin. However, Blockchain technology can also
be applied to many other areas. For example, in a cloud
service using Blockchain technology, an environment
can be created for smart contracts and peer-to-peer data
sharing (Swan, 2015). Data integrity, which is the strong
point of Blockchain technology, is the reason its use has
spread to other services and applications.
Blockchain technology enables the participants in the
network to execute transactions without third-party val-
idation, even if the parties do not have mutual interests.
Therefore, an agreement between a buyer and a seller can
be achieved faster by eliminating intermediaries. When
the data on the chains are encrypted, there is no need for
central authority. Blockchain smart contracts automati-
cally execute files or named scripts that are integrated
with each other evenly in a smooth manner (Christidis &
Devetsikiotis, 2016). Within the framework of the agree-
ment made with the application of the Blockchain smart
contracts, payment terms, conditions and processing
steps are determined, then all these steps are implement-
ed without additional third-party verification.
The idea of smart contracts was first proposed by Nick
Szabo in 1997 (Nick Szabo, 2018). However, the idea of
using Blockchain to track ownership status and trans-
fer of ownership was first described by Mike Hearn in
the article “Smart Property” (Mike Hearn, 2018). After
Blockchain technology became increasingly widespread,
Blockchain smart contracts gained popularity and many
applications emerged. Ethereum and Hyperledger are the
most popular applications of smart contracts and numer-
ous applications can be developed using these platforms.
Ethereum
When we look at the popular applications that offer smart
contract infrastructure, Ethereum is the most notable ex-
ample. Ethereum is crypto money like Bitcoin and is based
on a decentralized structure using Blockchain technology.
The main difference between Ethereum and Bitcoin is that
Ethereum allows a number of smart contracts (Founder
& Gavin, 2017). Ethereum, designed and coded by Vitalik
Buterin and his team, was first launched at the Bitcoin
Conference on July 30, 2015. Ethereum offers the most
widely used smart contract infrastructure. Various studies
have been done with this useful application and experts
have emphasized that Ethereum can be transformed into a
platform for smart contracts (Huh et al., 2017).
Photogrammetric Engineering & Remote Sensing
Vol. 86, No. 1, January 2020, pp. 5–10.
0099-1112/20/5–10
© 2020 American Society for Photogrammetry
and Remote Sensing
doi: 10.14358/PERS.86.1.5
