Machine Learning Approaches for Convergence of IoT and Blockchain. Группа авторов

life at stake. Specialization and accuracy form its foundation. In any condition ranging from minor discomfort, fever to emergencies such as a fracture or heart attack are all taken care of by this sector. The composition of the services it provides covers prevention, diagnosis, treatment, and medical rehabilitation. Herein, it is essential to keep accurate and updated records of the available drugs as in case a patient requires its administration it must be available and should be well within its shelf life. Hospitals need to maintain proper records of the patient who have been treated and store case history along with the treatment provided to any individual. For patients suffering from a chronic disease, case history must be available in case the patient is brought in emergency. This industry also performs surgeries and transplants in keeping with procedures to cure or lengthen the life span of the patients. In this process, certain highly specialized surgeries are sometimes conducted which require sophisticated equipment and knowledge.

      1.2.5 Military

This industry comes under the tertiary sector as it is a form a service to a nation and its citizens. The Indian Armed Force is under the Government of India and is managed by the Ministry of Defence (MoD). India possesses the world’s second largest military after China. The military service in India serves in three three wings each for a different landform. The three arms are the Army, the Air Force, and the Navy. The Army is the ground force that battles any threat that prevails in their country on land. The Air force is the unit that takes charge of all the aerial operations and security. The naval force maintains the safety of the waters that come under the jurisdiction of the country. All these forces have officers that are allotted various ranks and positions according to their specialization; the highest rank is that of the chief who also holds the responsibility of making all the crucial decisions. Each officer has to qualify for the National Defence Academy (NDA) where they undergo rigorous training and are toughened to withstand extreme conditions. This indeed is one of the most disciplined industries of all. This industry’s peculiar feature is the intelligence service, who serves to keep a close watch on the activities in and around the country, they also keep a close watch on the happenings of their rival countries to ensure that if there happens to be any threat to their country, they’re sufficiently prepared to counteract. India has the world’s third largest defence budget which enables it to equip itself with aircrafts and other machinery that are par above other countries.

      1.2.6 IT Industry

      IT industry stands for Information and technology industry [2]. IT sector has been majorly responsible for transforming India into a global economy since we have received multiple outsourced and mediated technology-based work contracts. These are the companies that provide us with computing solutions as well as other hardware and software applications such as Intel, Hcl, and Apple. Utilization of computers for storage, transmission, manipulation and retrieval of data or information is the basis of this type of industry. This sector has gained advancement and has enlarged considerably in our country over the last few years, generating employment for a huge chunk of the population and also contributing to the country’s overall economy. The major IT hubs in India are Bangalore, Chennai, Noida, and Hyderabad. The initial wave of the IT industry that we see today was first established when the government set up the Software Technology Parks of India (STPI) in the early 90s. Let us consider a day-to-day life scenario as an example to understand the services and features of the IT industry. So, consider that a person is facing trouble with the signal strength on his mobile device. He will convey his problem to the customer care service that the network company offers. They will then work toward tracing the cause of inconvenience, if it is a faulty sim card or a trouble with the signal tower of that area and then work for providing a solution at the earliest possible. Network provider is one type of industry that comes under the IT sector; many such companies exist under this sector functioning under the umbrella of information and technology.

1.3 What is Blockchain?

In layman’s language we may understand it as a chain of blocks containing information as illustrated in Figure 1.2. The original purpose of blockchain was to time stamp documents however it did not find much application [3]. The blockchain majorly picked up popularity when it was adapted to create a digital cryptocurrency—Bitcoin, by Satoshi Nakamoto in 2009. The most prominent feature of blockchain is that once any information is entered, it is nearly impossible to edit or delete it. Each block in a blockchain has three components associated to it, which are data, hash, and hash of the previous block. The data of a block contains information relevant to the purpose which the chain is utilized for. The next component, i.e., hash is like the finger print of the block and is thus unique to every block. The hash of a block is calculated after the data in entered. Therefore, if the content of any block is tampered with, it, in turn, changes the hash, and hence, it is no longer the same block, and this feature particularly allows us to ensure that any information once entered in a blockchain cannot be modified or deleted. The third component of a block is the hash of the previous block. Each block contains the hash of the previous block which enables the chain formation. If any block in this chain is modified, its hash changes, hence breaking the linkage through the entire length of the chain, disrupting the entire chain formation. This is how the safety and integrity of any blockchain is ensured. The first block of a blockchain is referred to as genesis block.

Figure 1.2 Illustration of blockchain technology.

Let us now understand how blockchain ensures a high level of security. Firstly, since each block contains the hash of the previous block, it is not possible to modify the content of any block without disrupting the chain henceforth. Secondly, this technology follows a practice called proof of work. Hashes are insufficient to ensure protection because computers these days are fast enough to recalculate all the hashes of the blocks within seconds; this is where proof of work comes into the picture. Through this method, we considerably increase the time required to calculate the hash of a single block. These two features when put together enhance the security mechanism. Thirdly, the entire blockchain in available to all its users; in other words, we may say that a blockchain is distributed. This peer-to-peer network enables all members to receive any new block that is formed; it is then verified by each node and is given consensus, only then it is incorporated into the chain. So, in case a block comes up that is tampered with it will be rejected be the other nodes [4]. The benefits of this architecture as observed are tamper-proof nature and better traceability along with resolving trust issues that may otherwise interrupt the supply chain [5]. Blockchain can fall under two categories private and public. A public blockchain is a completely transparent ledger and is decentralized. The information in this platform is encrypted and can be accessed on multiple devices. A public blockchain is nearly impossible to hack, as that will require acceptance from at least 51% of the nodes which is very difficult to attain for a malicious task, as the total number of nodes connected to this chain is very large. In contrast, a private blockchain has a limited audience that can access the content stored on the blockchain. It is an invitation only blockchain and is under the control of a single entity, hence not decentralized. A public blockchain is comparatively more secure than a private one.

      Although every user in the network has access to all the blocks, not complete knowledge of any transaction or activity may be gained by all users. The details of all transactions are encrypted. For examples, if user A buys apples from user B via this network, the other users can know that there has been a transaction but would not attain all details, i.e., they may know that there has been a transaction but may not know that is was held for the exchange of apples. Most of the platforms or services that we use today be it Facebook or Google are centralized in nature and they have a lot of control in terms of privacy, and you may not be willing to give any one entity access to all your data. So, blockchain technology overcomes this concern where no one node or entity can have monotonous control or access to any piece of information.

The