Towards Blockchainizing Land Valuation Certificate Management Procedures in Vietnam Ngoc-Hoa Nguyen Binh Minh Nguyen∗ VNU University of Engineering and Technology Vietnam National University Hanoi, Vietnam hoa.nguyen@vnu.edu.vn School of Information and Communication Technology Hanoi University of Science and Technology Hanoi, Vietnam minhnb@soict.hust.edu.vn Thanh-Chung Dao Ba-Lam Do School of Information and Communication Technology Hanoi University of Science and Technology Hanoi, Vietnam chungdt@soict.hust.edu.vn School of Information and Communication Technology Hanoi University of Science and Technology Hanoi, Vietnam lamdb@soict.hust.edu.vn Abstract—In this paper, we concentrate on the process of managing the land valuation certificate using blockchain in Vietnam To approach this problem, we base on the e-government application framework published by the Ministry of Information and Communication and Ministry of Natural Resources and Environment to develop a blockchain-based component which will be linked to the framework Our component has three layers corresponding to three main layers of the architecture After that, we develop a decentralized application serving the procedures of land valuation certificate management With our application, certificates are stored and can be traced from the blockchain network Our component hence helps create the transparency of management processes We also carry out preliminary experiments using the proposed system to prove its feasibility during test operation processes Our research also paves the way for applying blockchain technology to the state management field in general Index Terms—Blockchain, blockchainize, decentralized application development, land valuation certificate management, egovernment application framework, Hyperledger Fabric I I NTRODUCTION Blockchain covers many technological components such as peer-to-peer network, encryption, consensus algorithm, broadcast communication, fault-tolerance, data consistency, and so on The technology promises to change every life aspect thanks to the increase of trust among different parties about data and minimizing complex paper processes Once data is stored as transactions inside blocks in the chain, it cannot be altered by others Hence, blockchain brings security benefits exceeding anything that traditional, centralized server-based storage can provide today Currently, many countries and organizations around the world have initially applied blockchain technology to the field of land management The most outstanding one is the solution of the Propy [1], which aims to provide international ∗ Corresponding author real-estate transactions by creating an online application and a property transaction platform for the global real estate industry The Propy platform improves transparency for transactions while reducing the complexity of the land sale and purchase process through using core technologies that are related to blockchain, mobile, cloud technologies that link buyers, sellers, and investors worldwide Lantmateriet is one of Sweden’s oldest public authorities Initially, as most countries in the world, land registration was presented on paper, which was a way to secure an ownership record of an individual or organization By 1970, Lantmateriet [2] was one of the first agencies in the world to digitize land registers Not all processes were digitized at that time, but Lantmateriet had shown expectations and changes when taking advantage of new technologies Next, in 2016, a new project began when Lantmateriet, in collaboration with ChromaWay [3], decided to invest in researching how to apply blockchain and smart contracts to real estate transactions The process of buying and selling land thus was carried out quickly compared to the traditional way In Vietnam, with the current state management, land management is one of the most burning issues, especially in urban areas and places where many transactions are highly valuable Most of the policies and tools currently used for land management in Vietnam are still associated with relatively standard technologies, such as the use of geospatial data, RDBMS records, and land use rights certificates issued In which all land use rights granted to individuals and organizations use traditional paper One of the reasons is that land is a valuable asset, and the authorities have not believed in technological solutions However, land transactions take place continuously, which are often updated on paper records system, but they are rarely updated on database systems As a result, for a while, land databases have become obsolete Specifically, the land information could not share for other Authorized licensed use limited to: University of Vermont Libraries Downloaded on July 27,2020 at 11:07:30 UTC from IEEE Xplore Restrictions apply state management activities such as planning, taxes, property, construction management, urban, transportation, and so forth Hence, finding suitable technology for the land management problem in Vietnam is very urgent today Recently, blockchain has been evaluated as the future of land registration due to its benefits First, this technology has the potential to reduce property fraud, land transactions significantly Next, records related to land transactions stored on a blockchain can quickly accelerate the speed of execution and transparency among actors (e.g., sellers, buyers, and brokers), as well as reducing costs In this paper, we introduce a land management system using blockchain technology in Vietnam At the early stage, our system focuses on blockchainizing the land valuation certificate management procedure as a demonstration for the whole proposed system We employ the Hyperledger Fabric network [4] as a blockchain engine to deploy our system In this way, our main contribution is to investigate and implement proofs of concepts for land management in Vietnam with the starting point is the land valuation certificate management using blockchain technology Technically, we also defined a general solution in blockchainizing state management procedures using our blockchain component integrated with the e-government architecture framework The blockchain component thus can support developers in building decentralized applications based on pre-defined services Besides, thanks to this component, many blockchain engines (e.g., Fabric, Sawtooth, IPFS) can be employed efficiently Our paper has the following structure In the next section, we present and analyze the existing works, which are related to land management using blockchain to highlight our contributions in this study In Section III, we describe the current issuance of land valuation certificate procedures in Vietnam In Section IV, we introduce the design for our proposed system in detail The experiments and evaluations for our proposals are presented in Section V Finally, we conclude and point out the future works in the last section II R ELATED W ORK Blockchainization or using blockchain as back-end is gradually applied to various application fields, especially those requiring high transparency and immutable data There are some works describing challenges and strategies of blockchainization [5] that have raised problems in developing decentralized applications including network types, consensus algorithms, and data model The paper described strategies when the authors built a system of issuing school and university certificates based on blockchain technology Blockchainization offered opportunities in data management that helps users control and monitor their data [6] There is a trend of applying blockchain in different domains including public policy [7], education [8], and finance [9] The work presented in this paper can be classified into the research group dealing with the blockchainizing real applications Recently, blockchain technology has been applied to land management field in smart city and e-government systems in several countries such as Sweden [3], [10] and Estonia [11] The purpose of using blockchain is to increase transparency, and traceability in state management In this work [12], the authors tested a land register system using Bitcoin technology that involved banks, government, brokers, buyers, and sellers The system also provided the ability of tracking deal progresses In [13], the authors used blockchain to avoid government corruption, frauds, and bubbles in real estate market in which smart contracts are deals among sellers, and byers that are pre-defined and automatically executed This has helped remove intermediate parties in contracts between buyers and seller In this work [14], the authors proposed a blockchain-based system providing smart contract services to support users to define contract for renting buildings, houses, and offices Although there are many proofs of concepts in applying blockchain to land management in the world, to the best of our knowledge, there has been no work of blockchain usage for real estate field in Vietnam, especially to support the state management of national agencies The reason might be that land management is different in each country, so the above related work is hard to apply to Vietnam’s situation III L AND VALUATION C ERTIFICATE P ROCEDURES IN V IETNAM In 2015, the Ministry of Information and Communications (MIC) issued E-Government Architecture Framework [15] From the framework, the Ministry of Natural Resources and Environment (MONRE) has built an e-government architecture framework for the private sectors of the Ministry [16] After that, the Minister of Natural Resources and Environment has published Decision No 2555/QD-BTNMT with a list of administrative procedures in the field of land management [17] Up to now, most of the administrative procedures issued under Decision No 2555/QD-BTNMT [17] have been implemented; however, their whole level of those systems depends on each locality With the situation of building e-government in Vietnam in general, and at MONRE in particular, it can be seen that there are many land management procedures that still must be digitized at the time even though the e-Government Architecture Framework was built a long time ago Furthermore, applying blockchain technology to the business processes thus still has a significant barrier Our long-term plan is to develop blockchain-based public services that meet each administrative procedure requirement in land management However, in the short term, the issuance, replacement, and re-issuance land valuation certificates service using blockchain technology (representing services at the central level) is developed at an initial phase The current entire land valuation certificate procedure is illustrated by Figure The current offline procedures for the issuance, replacement, and re-issuance of land valuation certificate are as follows: Step - application submission: the applicant of issuance, replacement, or re-issuance submits a set of documents to the MONRE office directly He/she also can send by post to Authorized licensed use limited to: University of Vermont Libraries Downloaded on July 27,2020 at 11:07:30 UTC from IEEE Xplore Restrictions apply General Department of Land Administration Sector that receives and returns results Individuals and organizations CURRENT ISSUANCE PROCEDURE OF LAND VALUATION CERTIFICATE Begin 3.1 Receive notification of original submission date Receive the results Submit application file Check documentation Return the results Not Pass Notice of original submission 2.1 Request for additional documentations Pass Receiving applications Submit applications 7.1 Compose and sign the rejection document Not meet condition Check documentations Eligible Compose and sign the accept document Fig Issuance procedures of land valuation certificates this office Step - documenting assessment: the applicationreceiver is responsible for checking, confirming, and writing the appointment date to return the result to the applicant if that application is complete while supplementing documents should be noticed when lacking something If the application is sent via post, the receiver will confirm the application situation by email or phone Step - verification: the General Department of Land Administration is responsible for examining the documents In case of eligibility for issuing or re-issuing land valuation certificate, the General Director of the General Department of Land Administration considers and signs the decision to issue, re-issue land valuation certificate within 15 days from the date of receiving complete and valid dossiers In case of disqualification, the Director of the General Department of Land Administration signs documentation that refuses to issue, re-issues land valuation certificates Step - returning results: the General Department of Land Administration is responsible for sending the certificate of land valuation to the return-results office within one working day from the date on which the decision on issuance, replacement, re-issuance is signed IV D ESIGNING S YSTEM A Overall Architecture Basically, the MONRE architecture includes four main components, namely: (1) Infrastructures: a component that offers storage, computation, network, and virtualization (i.e., cloud) services deployed on physical servers belonging to data centers managed by MONRE and its member agencies (2) Databases: a set of different databases to store data in unified forms Thus, the data can be shared among MONRE’s departments effectively (3) Core and integration services: prewritten services that support critical business processes of MONRE as well as allow connecting and sharing data among internal subsystems And (4) Applications that are developed based on the Core services serving specific operation field of MONRE Based on the existing architecture, we design a new blockchain component that links with the original one In this way, the component is divided into several layers, covering: blockchain engine, a blockchain-based platform, and decentralized applications The goals of these layers are also similar to the top three layers of MONRE’s architecture Concretely, the blockchain component is deployed on computation, virtualization, and network infrastructures of MONRE’s e-Government Architecture Framework Meanwhile, the blockchain engine plays the role of storing data using several technologies Due to the particularities of state management operations (i.e., national data security, and Vietnamese network security law - which forces Vietnam’s data to be stored in data centers located inside Vietnam), the system cannot rely on permissionless blockchain network (e.g., Ethereum [18]) Therefore, we use open source blockchain engines like Hyperledger Fabric to deploy blockchain network Besides, to add the openness feature for the network, we also enable Fabric integration with other engines (e.g., Hyperledger Sawtooth [19]) There are three reasons for choosing Fabric here: (1) this engine is supported by a large consortium of many company members (2) Fabric is also one of the active open source projects, which is committed daily (3) as compared with others, the engine’s official releases are more stable and are downloaded as well as deployed widely To store data in a decentralized manner, we use InterPlanetary File System (IPFS) [20], which is a peer-to-peer (P2P) file-sharing system and BigChainDB [21], which is a scalable blockchain database for big data storage Although Hyperledger Fabric and other open-source engines offer the capability of deploying blockchain networks in a permissioned way, exploiting the engines to serve real problems is still difficult because applications often demand more services to meet specific requirements Hence, in our design, we build a blockchain-based platform in order to provide common process functionalities for the development and deployment of decentralized applications The blockchain-based platform thus can be considered as an extension of the core services layer in MONRE’s e-Government Architecture Framework The platform is composed of the following services: • Identification: integrates with the digital signature system of MONRE to authorize and authenticate users, who can interact with data stored on the blockchain, especially those who can sign on e-certificates (e.g., Director of Land General Department) This identification information can be shared and used among diverse applications • Data mapping model: maps application data of different types into a key-value form according to the way of Authorized licensed use limited to: University of Vermont Libraries Downloaded on July 27,2020 at 11:07:30 UTC from IEEE Xplore Restrictions apply Display information Public service in receiving and returning application results Other public services Public services in environment field Public services in meteorology, hydrology and climate change Public services in mineral geology Public services in land field Public services in measurement and maps Public services in water resource Public services for remote sensing Public services for sea and island Blockchainizing Applications Land Valuation Certificate Management Registration of changes use rights ownership of properties attached to land Registration of lease, sublease or capital contribution with land use rights … Decentralized applications Core Services System management Statistic report User management Workflow management Content management Portal management Validate digital text infor Unstructured data mngt Online payment Infrastructure mngt and monitoring System integration mngt Spatial data management Enterprise Service Bus Workflow Process Share Storage Reports, Statistical Files Computation Identification Smart contract Data mapping Consensus Monitoring Deployment Blockchain-based platform Hyperledger Fabric Hyperledger Sawtooth IPFS BigChainDB Specific Domains Blockchain engines Virtualization Network Fig Overall architecture of MONRE’s e-government application framework with proposed blockchain-based component • • • • storing data as transactions inside blocks Besides, this service also calls suitable blockchain storage to store data For instance, large files can be stored in an IPFS network, then the hash of these files will be packed in the blockchain Smart contract: provides intuitive APIs that enable the developers to define business processes as usual (i.e., via their familiar programming languages) without knowledge about writing smart contracts (that may depend on blockchain engines) Consensus: almost all public services in the state management field not require special consensus protocols because there is no encouragement (i.e., mining, cryptocurrency) The important point is that national agencies must have system control permission At the beginning state, the consensus service may only offer messaging queues for packing blocks rather than complex ones However, in the future, according to the requirement of procedures, this service can be extended to provide many consensus mechanisms Monitoring: this service allows assessing the state of transactions, blockchain system health, application operation situations to help managers ensure the system availability, and prevent failure occurrences Deployment: provides deployment and configuration tools for individuals or organizations to deploy system blockchain peers on their sides in an easy way The platform introduced above also can be extended by adding more services according to requirements that may occur in the future With the ready-to-use blockchain-based platform, developers can create decentralized applications in a fast manner without caring about the blockchain knowledge The land valuation certificate management procedure is considered as one of the decentralized applications The overall design architecture of the blockchain component and the integration with MONRE’s e-Government Architecture Framework is shown in Figure B Blockchain-based Operation Flow The blockchain-based processes of issuing and verifying land certificates are illustrated in Figure This flow is developed based on the current procedures, as presented in Section III These processes are carried out as follows: 1) Applicants submit an application to the application receiving service office (step 1) This application’s documentation often is in both forms of paper and electronic versions 2) The receiving office checks the completion of application documentations If the documents are complete, they are sent to the department/general department officer for the next process and sent back to the applicant in the opposite case (step 2) 3) The department/general department officer checks the legality of application documentations (step 3) If the documents are in accordance with the regulations, the electronic version is signed by the officer using his/her private key At the same time, the application paper Authorized licensed use limited to: University of Vermont Libraries Downloaded on July 27,2020 at 11:07:30 UTC from IEEE Xplore Restrictions apply Application Receiving Office Check the completion of documentations Department officer Check the legality of documentations and sign by his/her private key Director of Land General Department Sign ecertificate by his private key 5b Return results Submit application Issue certificate attached to ecertificate on blockchain Applicants Provide ecertificate to verify certificate on blockchain 5a Broadcast Land Valuation Organizations Blockchain Network Fig Blockchain-based processes of land valuation certificate issuance and verification 4) 5) 6) 7) version also is signed After that, all versions are sent to the Director of Land General Department If the documentation does not suit the regulation, they will be sent back to the applicants Director of Land General Department examines and signs (step 4) both application documentation versions (by his/her private key with the electronic version) The confirmation data (e-certificate) thus will be stored on the blockchain as a transaction to broadcast to peers (step 5a); meanwhile, the paper certificate is issued and sent back to the Application Receiving Office to announce to the applicant (step 5b) The applicant receives a certificate issued on paper that attached to e-certificate information (hash code) stored on the blockchain (step 6) The applicant can provide an e-certificate to Land Valuation Organizations if needed The organizations can search the hash code (e-certificate) on the blockchain network (step 7) The processes of certificate issuance using blockchain designed above not only meet the requirements of the current procedure in land valuation certificate management but also help digitalize that procedure Besides, other processes of certificate re-issuance and exchange can be performed in a similar way of issuance presented above V E XPERIMENT The purpose of this section is to experiment, evaluate, and show the potential of applying blockchain to issue the land valuation certificate Thus, we built a private blockchain network among management departments of Land general department and national agencies of provinces Based on that blockchain network, we created transactions containing land valuation certificates and send them to the network We measure how many transactions could be processed each second and figure out that the proposed prototype can work well and the real deployment is possible in practice Fig Performance of issuing land valuation certificates A Private Blockchain Network A private network is more relevant since data stored in blocks must be securely protected and controlled by the management Land General department Although it is a private blockchain network, land valuation certificates are readable from public by land valuation organizations, companies, and individuals If any organizations or individuals want to check the certificate information, they can access a public endpoint of the network (i.e blockchain peers) Even, it is possible to clone the current chain to a user’s local machines As mentioned above, we have chosen Hyperledger Fabric as our blockchain network in this experiment In the Fabric deployment architecture, there are two organizations which are representative for two clusters of peers (each organization is a department in practice) Each organization has three data peers and one certificate authentication (CA) peer In addition, the architecture also includes a cluster of four ordering service peers as recommendation in the Fabric deployment tutorial So, we deployed 12 servers in total These servers are virtual machines, each of them has the following configurations: vCPU (2.3 GHz), 8GB of memory, 80GB of SSD hard drive Connections among physical servers inside the organizations, and ordering service cluster (i.e data centers) use InfiniBand technology (40 Gbps) The connections between two organizations, and ordering service are the Internet (across three separate data centers in the same city) The architecture and configurations in this test enable us to build the real network, communication, committing transactions of blockchain testbed B Transaction Performance To evaluate the performance of the built system, we conducted a stress test by sending transactions of issuing land valuation certificates to the private blockchain network The transaction rate is increased in each measurement and the processing time is recorded We conducted the experiment ten times and calculated the average value The gained results are Authorized licensed use limited to: University of Vermont Libraries Downloaded on July 27,2020 at 11:07:30 UTC from IEEE Xplore Restrictions apply 50% of all requests 222.45 ms 75% of all requests 372.66 ms ACKNOWLEDGMENT This work is supported by the Vietnam national project "Research on building an online public service in the field of land management using blockchain technology" under project number KC.01.27/16-20 90% of all requests 586.72 ms R EFERENCES 100% of all requests 981.07 ms TABLE I T HROUGHPUT OF TYPICAL REQUESTS Latency Throughput: 393.84 requests/second TABLE II T HROUGHPUT OF ISSUING LAND VALUATION CERTIFICATES Latency 50% of all requests 430.48 ms 75% of all requests 625.14 ms 90% of all requests 848.86 ms 100% of all requests 1580 ms Throughput: 210.20 requests/second shown in Figure When the number of transactions is small, processing time is less than 200 milliseconds The processing time means how many transactions are validated and packaged in blocks The processing time increased sharply when the number of transactions is more than 1000 The reason is that there is a limitation of transaction number that can be packaged in a block C Throughput of Reading Requests The purpose of this experiment is to show the latency and throughput of reading requests sent to the blockchain network For each reading request, the returned message could be empty or containing certificate’s information Table I shows latency and throughput when the returned message contains no certificate data The throughput is 393.84 requests per second Table II reveals that latency is increased and throughput is decreased when the returned data contains certificates’ information VI C ONCLUSION AND F UTURE W ORK In this paper, we presented our designs and preliminary tests for blockchainizing land valuation certificate management procedures in Vietnam In this direction, we concentrated on analyzing the e-Government Architecture Framework of MONRE, and the current procedures of land valuation certificate management Then we built a blockchain-based component, including three layers that integrate with the MONRE’s Framework For the land valuation certificate management, we designed the blockchain-based services, which support to issue the certificate in both forms of paper and electronic versions The blockchain network thus helps store and trace e-certificate in an effective way Through experiments, we showed the operability and feasibility of our proposals in practice In the future, we will continue to evaluate the blockchain-based component to test the performance of blockchain engines, and the operability of pre-written blockchain services [1] P Inc The next generation real estate transaction management software [Online] Available: https://propy.com/browse/ [2] Lantmateriet Swedish mapping, cadastral and land registration authority [Online] Available: https://www.lantmateriet.se/ [3] J McMurren, A Young, and S Verhulst, “Addressing transaction costs through blockchain and identity in swedish land transfers,” 2018 [4] C Cachin, “Architecture of the hyperledger blockchain fabric,” in Workshop on distributed cryptocurrencies and consensus ledgers, vol 310, 2016, p [5] T C Dao, B M Nguyen, and B L Do, “Challenges and strategies for developing decentralized applications based on blockchain technology,” in International Conference on Advanced Information Networking and Applications Springer, 2019, pp 952–962 [6] F.-Y Wang, Y Yuan, J Zhang, R Qin, and M H Smith, “Blockchainized internet of minds: A new opportunity for cyber– physical–social systems,” IEEE Transactions on Computational Social Systems, vol 5, no 4, pp 897–906, 2018 [7] S Muftic, “Blockchain identity management system based on public identities ledger,” Apr 2017, uS Patent 9,635,000 [8] P Schmidt, “Blockcerts—an open infrastructure for academic credentials on the blockchain,” MLLearning, 2016 [9] R Lewis, J McPartland, and R Ranjan, “Blockchain and financial market innovation,” Economic Perspectives, vol 41, no 7, pp 1–17, 2017 [10] D Fernando and N Ranasinghe, “Permissioned distributed ledgers for land transactions; a case study,” in International Conference on Business Process Management Springer, 2019, pp 136–150 [11] C Sullivan and E Burger, “E-residency and blockchain,” computer law & security review, vol 33, no 4, pp 470–481, 2017 [12] G Chavez-Dreyfuss, “Sweden tests blockchain technology for land registry,” Reuters, June, vol 16, 2016 [13] B Verheye, “Real estate publicity in a blockchain world: a critical assessment,” European Property Law Journal, vol 6, no 3, pp 441–476, 2017 [14] I Karamitsos, M Papadaki, and N B Al Barghuthi, “Design of the blockchain smart contract: a use case for real estate,” Journal of Information Security, vol 9, no 03, p 177, 2018 [15] M of Information and Communicatoin E-government architecture framework published by mic, decision no 1178/btttt-thh, version 1.0 [Online] Available: http://aita.gov.vn/Uploaded/Khung%20Kien%20tr uc%20CPDT%20VN%20V1_0%282%29.pdf [16] M of Natural Resources and Environment E-government architecture framework for monre, decision no 3339/qÐ-ntnmt, version 1.0 [Online] Available: http://dinte.gov.vn/TinTuc/Lists/TaiLieu/Attachme nts/31/KT%20CPDT%20Bo%20TNMT-v1.0b.pdf [17] —— Newly promulgated administrative procedures; be amended and supplemented in the field of land under the state management of the ministry of natural resources and environment [Online] Available: https://thuvienphapluat.vn/van-ban/bat-dong-san/Quyet-dinh-2555-QD -BTNMT-2017-cong-bo-thu-tuc-hanh-chinh-linh-vuc-dat-dai-Bo-tai-n guyen-369123.aspx [18] G Wood et al., “Ethereum: A secure decentralised generalised transaction ledger,” Ethereum project yellow paper, vol 151, no 2014, pp 1–32, 2014 [19] B Ampel, M Patton, and H Chen, “Performance modeling of hyperledger sawtooth blockchain,” in 2019 IEEE International Conference on Intelligence and Security Informatics (ISI) IEEE, 2019, pp 59–61 [20] E Nyaletey, R M Parizi, Q Zhang, and K.-K R Choo, “Blockipfs– blockchain-enabled interplanetary file system for forensic and trusted data traceability,” in 2nd IEEE International Conference on Blockchain (IEEE Blockchain-2019), 2019 [21] T McConaghy, R Marques, A Müller, D De Jonghe, T McConaghy, G McMullen, R Henderson, S Bellemare, and A Granzotto, “Bigchaindb: a scalable blockchain database,” white paper, BigChainDB, 2016 Authorized licensed use limited to: University of Vermont Libraries Downloaded on July 27,2020 at 11:07:30 UTC from IEEE Xplore Restrictions apply ... valuation certificate management using blockchain technology Technically, we also defined a general solution in blockchainizing state management procedures using our blockchain component integrated... this paper, we introduce a land management system using blockchain technology in Vietnam At the early stage, our system focuses on blockchainizing the land valuation certificate management procedure... blockchain engine to deploy our system In this way, our main contribution is to investigate and implement proofs of concepts for land management in Vietnam with the starting point is the land valuation