44

Blockchain Technology

which further increases transaction numbers. With the scalable architec­

ture and increasing number of transactions of the Blockchain ledger, the

need for more storage comes into the picture, which can be met using cloud

storage solutions in the next phase, where various backups and replications

needed will make the whole system more complex.

• Processing Power and Time: There are several encryption algorithms

used in integrating Blockchain with IoT technology. The ecosystem of the

IoT provides a different paradigm for the computing capabilities and secu­

rity algorithms contained in it, requiring more and more processing power.

• Shortage of Experienced and Skilled Developers: One of the most prom­

inent issues in integrated technology is the shortage of skilled employees.

The two technologies are poles apart, and the integration requires personnel

with the skills to develop and handle this.

• Policy Management, Legal Guidance and Compliance: The policy man­

agement and legal compliance are again an important concern in the case

of the Blockchained IoT ecosystem. The policies related to privacy of the

data may vary from place to place, so the algorithms used in the integration

should have common derivatives.

• Complexities of Hybrid and Integrated Structure: As discussed, both

the fields are emerging and complex in nature, so the amalgamation of both

technologies will give rise to more complex systems. The current IoT eco­

systems bank on the centralized system and client server communication

models, whereas Blockchain is a decentralized technology. The resource

constraints and infrastructural requirements will make the system difficult

to implement and handle.

• Security Issues: Current IoT systems do not offer multi-factor authentica­

tion. The market for Blockchain as a service is very new, and the processing

power needs can be an issue in physical systems, so the whole system is

dependent on the cloud. So, vendor-level risks are associated with the tech­

nology, which needs to be addressed. The IoT components must be durably

connected to the block network to participate in the process generated by

Blockchain to ensure reliability.

Besides these basic challenges, some of the major attacks on the Blockchain described

here with their analysis in various reviewed studies of Blockchained IoT, mentioned

in Table 3.2, are described in brief in Table 3.4.

• Denial of Service (DoS) Attack

The invader attempts to prevent the authentic user from accessing the

service in the network during such an attack. In these cases, the adversary

may start fraudulent transactions and may increase network traffic. Random

users cannot access the network in our program, however, without evidence

of authority. Nevertheless, assume that an adversary invades the network

and begins to send fake transactions to the network. For such a scenario,

the cluster head will search the public address, and if it is not available or