The implementation of Blockchain framework in MOOCs to support a freedom of learning in Indonesia

A freedom of learning program has been released by the Indonesian Ministry and Culture this year 2020. There are three ways for students to earn their credits, namely take the subject course in face-to-face based class, virtual based class or under Massive Open Online Courses (MOOCs). MOOCs is a model that is developed to help people to learn about certain skills through the online platform, without any limitation in the audience. MOOCs aim to enhance broad collaboration between individuals in creating learning environments that have high scalability and can be accessed by anyone and anywhere. The complexity arises when students undertake a subject course through MOOCs, how to certify the completion of their program in which the certification can be gained easily, and the last how secure the obtained certificate? Blockchain technology can help to improve the quality of MOOCs by providing control of academic records as evidence that someone has completed a learning process on MOOCs. Academic records generated will be stored in one place forever and safely stored in the Blockchain environment. This article will explore how the possible to implement the Blockchain framework in MOOCs to support a freedom of learning in Indonesia.


Introduction
Education is a worthwhile investment for individuals to increase their quality of life in the fields of economics and social. Higher education guarantees long-term economic benefits to whoever does it, see Pouezevara et al. [5]. Moreover, education can enhance one's knowledge to become a professional in specific sectors in their life. To get new skills and insights, people can participate in a learning program provided by educational institutions such as universities or schools. Students are required to come to the universities or schools following the learning process, doing the assignments, and taking the exams to fulfill the prerequisite of graduation established by the educational institutions Nowadays, with the innovation of technology in the field of education, especially in the freedom of learning program endorsed by by the Indonesian Ministry and Culture 2020 [3], students can take online courses via the internet, more specifically through Learning Management System (LMS) platform. This type of learning process is considered to be online courses. There are many advantages of online course program, one of those is the absence of students coming to school classroom. They can joint the class anytime, anywhere and anyplace. It would be a great opportunity for students who want to get an education but unable to join the offline class. Currently, there is a new model of learning management system called Massive Open Online Courses (MOOCs). MOOCs have many benefits compared to the traditional online class, for example, it is opened for all components of the society, and it has no limitation of numbers of the audience. Furthermore, the audiences are free to  [4]. MOOCs also provide many options for courses that can be engaged in the student's interest.
Besides the advantages of MOOCs, acceptance of the MOOCs certificate, gotten after course completion, is required to be verified and validated. In this research, we identified several problems that must be solved to improve the quality of recognition of the certificates. The first problem is how to save certificate documents in long-lived storage. Secondly, to avoid a forgery certificate becomes more prevalent due to the ease of the use of software editing. When it is happened, it is difficult to distinguish between the original and the fake one. Without a reliable verification process on the certificate, unauthorized parties can be easily manipulated existing documents. Third, the other essential elements to pay attention are recognition, accessibility, and trustworthiness. Recognition means how stakeholders or institutions can easily recognize the original certificates. Next, accessibility means how stakeholders or institutions able to access certificates obtained by students. Last, trustworthiness is also an important point on certificates because it shows how much people trust the authenticity of the certificate.
There is a promising technology called Blockchain that can store data in a clear and tamperresistant manner which is implemented in a distributed network. When we talk about Blockchain, this technology reflects digital information stored in public databases, refers to Yaga et al. [11]. The hope is that Blockchain technology will be implemented in MOOCs so that certificates issued can be officially published and recognized and can also be stored permanently and cannot be deleted. With these problems and opportunities, we initiated a review of Blockchain technology so that it can be used to improve the quality of online certificates. Furthermore, since we implement the blockchain technology we need a secure management key to encrypt and decrypt the secret sharing key. For this purpose, we will use a labeling key, namely super (a,d)-H antimagic total labeling of graph. This article, we will explain the framework for implementing Blockchain technology in issuing certificates for MOOCs.

MOOCs
MOOCs (Massive Open Online Courses) are a disruptive technology of new online learning which has more advantages over traditional online courses. The advantages of MOOCs that are different from traditional online courses such as open to all components of people, have no limit on the number of students and can be accessed anytime / anywhere without any limits, see Pouezevara et al. [5].
MOOCs have four main components: Massive, Open, Online, and Course. Massive can be interpreted as providing accessible learning platforms to a large number of students who want learning at the same time. Open means that registration can be done by anyone, anywhere, and anytime without limitation. The online component means that the courses are taken entirely online via the internet. The last component is a course that has the same meaning as the courses in higher education, but it does not offer credit points.

Blockchain
Blockchain technology is a series of databases containing records of transactions. Blockchain technology has a distributed concept on computer networks to validate existing data. Unlike traditional databases, information on the blockchain cannot be manipulated because the model is built on a distributed nature and confirmed with guarantees by each peer/node. In a blockchain network, all nodes can access information from each other so that there is no central entity control. This concept makes blockchain technology different from the traditional database which has access to a single point/or several determined points, Sarmah [8]. In Figure 1 we can see the example of blockchain structure.
Based on figure 1, when someone makes a transaction on the blockchain network, to enter the existing chain, the transaction will be verified and validated using a computer algorithm to determine the authenticity of the data. Each block has a header and a series of transactions. The header contains

Transaction and data
In the blockchain component, there public records. On a transaction blo with any data that the sender wants the format is converted into hexade data field of a blockchain transactio blockchain requires validation by a records can be checked or re-valida [7].

Smart contract
A smart contract is a protocol that process. Smart contracts legally co approved based on the contract and order to comply with the self-execut the smart contract that has been dete

Decentralized Ledger
A decentralized ledger is a databas ledger can also be called a shared an in the network, see Sarmah [8]. T maximize the checking process of ledger is stored safely and accuratel accessed using correct cryptographi be available permanently and canno 2.5 The (ܽ, ݀) − ‫ܪ‬antimagic total la Given that a simple, and undirected integers to the either vertices or edg the different weight, see [2]. It is vertices.

Research methodology
Research methodology explains the framework of blockchain technolo below: ous block and the next block. Moreover, the heade hat the tracing process can be carried out to get the n technology also relies on hash technology to ensu or altered, Wang et. al [10].
e is a transaction which is defined as the smallest ockchain, there is a component called a data field th . The data in the transaction can be compiled in JSO cimal for the encoding process. The encoded data is on, Wang et. al [10]. The execution of transaction all nodes joined to the blockchain network. Previo ated but cannot be deleted or updated by further ste governs the blockchain platform which is based on ontrol documents are based on actions or events t d agreement, read Savelyev [9]. Implementing a sm tive principle, all entities and nodes must be involve ermined through the lines of program code Zhou et a se that is synchronized on all nodes in a network. A nd replicated database that stores transactional data f The decentralized ledger also eliminates the centr f data manipulation. All data or information on the ly using cryptographic methods. Data and informati ic keys and signatures. After the data is successfully ot be deleted according to the rules on the blockchain abelling graph G. By H antimagic total labeling, we mean an ges of G such that every evaluation of element sub said to be super if the smallest elements appear o e steps that will be conducted in qualitative research gy. The steps of research methodology can be se er also contains e chronological ure the data on unit stored on hat can be filled ON format then s entered in the records on the ous transaction eps Sabry et al.
n an automated that have been mart contract in d to implement al. [12].
A decentralized for all members ral authority to e decentralized ion can only be y stored, it will n network.

Internet Exploring
At the beginning of this research, exploring the internet was conducted to gain information about the enormous use of technology for education and training. Nowadays, we know that many online platforms were developed to deliver courses without any limitation of audiences. From this information, potential issues related to the massive use of open online platform were acquired. It leads the researchers to get the topic of this research.

Scientific Source Search
A scientific source search proposed to discover new information through study literature that systematically planned to gather important and relevant data. The researchers learn about the concept of blockchain technology and gain knowledge about MOOCs (Massive Open Online Courses) include its benefits and issues. One of those issues is about recognition of MOOCs certificate earned after completion.

Reading Process
Reading process aimed to understand the relation of every evidence of selected issue with the use of MOOC. This process also contains of issues breakdown which divide into five main points: retention, forgery avoidance, recognition, accessibility, and trustworthy.

Focus Group Discussion
Focus group discussion is gathering a group of people who have an idea to implement the blockchain technology in MOOCs system as a form of qualitative research. The group will be discussing about the problem related to MOOCs. They could share their perceptions, opinion, or ideas. The goal of this activity is to find the most suitable solution of MOOC certificate problem without decrease the value.

Reviewing and Analyzing Process
At the end of this research, the result of focus discussion group will be analyzed and examined to obtain needed framework to implement blockchain technology in issuing the certificate of MOOCs. In this research we try to make framework for the blockchain technology that has contribution to eliminate case of certificate forgery.

Recommendation
The last step will be carried out afte testing stage by making a final con after doing this research. The func research to improve the findings.

Blockchain for Improving MOO
In this section, we will discuss h Blockchain is expected to be able certificates issued by MOOCs prov supported by a smart contract, it w document forgery. The anytimecryptographic method will help to recognition, accessibility, and trus correct cryptographic keys and sig because it has been checked by a rel Frameworks for implementing b will be discussed in this section. T MOOCs providers to students who used for conducting a certificate ch certificates whose information is describes the framework for the issu  After finishing the course provider issues a certificate in the f represents a transaction with the cou to all nodes in the blockchain netwo synchronized across all nodes in a validation based on the smart cont validation process on the newly crea be added to the existing distribute permanent record of data. After the has been issued by the MOOCs pro certificates because it has been done Not only is the issuing certifi blockchain technology but also how the certificate. Figure 4 describes th er all the stages have been completed from the plann nclusion. Apart from that, the final step also includ ction of the recommendations is to provide suggest OCS ow blockchain can be used in issuing certificates to minimize the problems and improve the quality viders. With a distributed database and a validation will help to save documents in long-life storage a access blockchain network and validation proc o improve the three important elements of a certi stworthiness. Moreover, information can only be a gnatures. Eventually, it will increase user confid liable system. blockchain technology on the MOOCs system. Tw The first framework is a framework for issuing ce pass certain courses. The second framework is a fra hecking process which is useful for checking the needed by other stakeholders or institutions. Fi uing certificate process on the blockchain network.
Framework for issuing a certificate process.
f issuing a certificate that begins with the initiation e, The MOOCSs provides a certificate to the studen form of a transaction in the blockchain network. Th urse and student data will be created. The block is th ork to implement the distributed ledger concept. Th network. Each node on the network then carries ou tract that has been created. The smart contract wil ated block. When the validation process is accepted ed ledger which forms a chain that provides a tr e process is complete, the student legally receives a ovider. This concept is believed to improve the qua e through a sophisticated verification process. icate process by MOOCs providers important in w the institution or stakeholder can also check the e framework for checking the authenticity of certific ing stage to the des suggestions tions for future s for MOOCs. y of the course n system that is and also avoid cess using the ificate, namely accessed using dence and trust wo frameworks ertificates from amework that is authenticity of igure 3 below of the MOOCs nt. The MOOCs hen a block that hen broadcasted he block will be ut approval and ll automate the d, the block will ransparent and certificate that ality of existing n implementing authenticity of cates.

Figure
In Figure 4, there are two main a is a student who has passed a certain who will use certificate data, it c information about the authenticity blockchain network stores existing on the blockchain network. The de explanation below:

Certificate owners can acce
decryption process is manag 2. Certificate owners get the d the smart contract mechanis 3. User data can access certific the certificate. 4. User data gets feedback abo 5. Smart contracts access data provided by the user. 6. Smart contracts get inform given to users.
With this process, the validation minimize data falsification. Eventua system can improve the quality of th develop the secure encryption and Cipher Block Chaining (CBC) and graph in the CBC algorithm.

Encryption process by using gra
By the Framework 1, we can see b certificate document gained from M need a secret key such that it is diffi e 4. Framework for checking a certificate.
actors: the certificate owner and the data user. The ce n course and who received the certificate. The data u can be stakeholders or external institutions. Data of certificates for any event or process in their org certificate data so that each actor can reliably chec escription related to the framework in Figure 4 can The integration process of blockchain into MOOCs. ess their encrypted data by providing a secret key in ged by the smart contract. ecryption of their data stored on the blockchain with sm. cate data by providing a shared key to check the aut out the authenticity of the certificate. a on the public ledger to obtain information based mation about existing data from the blockchain net n or checking certificate process becomes more reli ally, the implementation of blockchain technology he certificates issued by the MOOCs provider.Furth d decryption data mentioned in above framework, d also integrate the super (ܽ, ݀) − ‫ܪ‬ antimagic to aph labelling for the key blockchain technology relies on the management ke MOOCs in. Thus, when we need to store the certific icult for any hacker to decrypt the data. We will use ertificate owner user is an actor a user requires ganization. for developing the secret key. The existing algorithm to establish a stream cipher under the mode of Cipher Block Chaining, we guide the reader to a published paper in [6]. We give an illustration of graph labelling of super (ܽ, ݀) − ‫ܪ‬ −antimagic total labelling of graph ‫,ܪ(݇ܿܽ‪ℎ‬ݏ‬ ‫,ݒ‬ ݊) to construct the encryption keys. Take a super (1351,39)-ܲ ଶ ▷ ܹ ହ -antimagic total labelling of graph ‫ܩ‬ = ‫ܥ‬ ହ ▷ ܹ ହ obtained in [1]. An established algorithm stated in [6] regarded to the development of stream cipher of Cipher Block Chaining by implementing the above super (a, d)-H antimagic total labelling of graph ‫,ܩ‬ see Figure 5 and Figure 6 for detail illustration.  The source key obtained from a layered diagram, see Figure 6, are 31,32,64,36,41,35,73,38,43,33,80,44,39,63,65,61,62,63,56,46,34,81,40,45,72,74. In modulo 26, they are 5, 6,12,10,15,9,21,12,17,7,2,18,13,11,13,9,10,11,4,20,8,3,14,19,20,22. Suppose the length of block is given by 3. We have the stream function is ݇ ାଷ = ݇ + ݇ ାଵ ‫݀݉‬ 26. The initial block key is ݇ = 5, 6, 12 and the key stream is (5,6,12), (11,18,22), (25, 24, 4), (7,3,24), (9,20,5) Furthermore, how does it work for the certificate completion document of MOOCs? We will give the following illustration in Table 1.Given that someone has finished on a specific course in MOOCs, namely "COMBINATORIALMATHSPYM". We consider the text COMBINATORIAL MATHS PYM" consist of the name of subject course is Combinatorial Mathematics, and the lecturer is Prof. Yung Ma (PYM), it is available in the Edx MOOCS. He has passed and gained a certificate. The smart contract developed the secret key by using graph and by means of Cipher Block Chaining. The smart contract can generate the ciphertext of "COMBINATORIALMATHSPYM" such that anyone will access the certificate, either the certificate owner and the data user can access through the the chipertext. For the detail how to encrypt the name of subject course and the name of the lecture who teach this course, it can be describe the following table.
The smart contract develop the secret key by mean of super (a,d)-H antimagic total labeling elements in Table 1. By mean of CBC, the encryption key as a chipper text is HUYTUHSLZQWXKCCBHQJAR. Certainly, this ciphertext is hard to reveal by any intruder or an authorised person. By doing the reverse the CBC algorithm we can have the plaintext again.

Conclusion
Blockchain is a new concept that offers many opportunities to solve problems related to transactional data. By implementing blockchain on issuing certificates on MOOCs, hopefully, it can solve problems such as storing documents in long-life storage, avoiding the document forgery, making it easy to access the MOOCs certificate, and improving trust or reliability from user data. The proposed framework is expected to be used as a reference for implementing blockchain technology on the MOOCs system. The future of blockchain technology is very promising, so further research is needed to discuss the existing challenges to maximize the effectiveness of using blockchain technology. Eventually, we expect that blockchain technology is not only used for successful implementations of financial technology or crypto currency but also is used to store other valuable assets. More specific case, respecting to the implementation of MOOCs together with a complex cryptosystem by using graph labelling can be integrated in learning management system such as MOOCs to support a freedom of learning program in Indonesia, to have a better quality of education.