# The Application of Blockchain in Social Media: A Systematic Literature Review
## 6 Discussion
### Research Question Answers
#### 6.1.2 The Existing Challenges and Limitations of Blockchain Application in Social Media  
There are substantial difficulties with the implementation of blockchain technologies. (a) The immutability of data can be a handicap  
Applying blockchains in social media networks cannot ensure that racist, homophobic, or culturally harmful comments will not be distributed. Any data that is stored in the blockchain will be there indefinitely. It cannot be removed or modified. Consequently, if a racist or offensive post is created on social media, the created information will remain there forever. It is almost impossible to punish the original user through the social blockchain because tracking the original user is impossible. In addition, members or site owners cannot remove members' data, even on request. (b) Scalability issues can make the platform slow  
Blockchains are not as scalable as their centralized counterpart systems. The scale of blockchain-based social media is relatively small, and blockchain nodes cannot afford to expand and deal with large flows of material. A centralized social platform can quickly and easily access its user database. With a blockchain, it may not be as quick and easy. A blockchain system does not scale proficiently, and has low scalability with massive amounts of information. These deficiencies have led to various attempts to manage social media's cumulative capacity, information, and content. (c) Energy Consumption Challenge  
In its initial introduction with bitcoin, blockchain employed the Proof-of-Work consensus algorithm. PoW relies on miners to accomplish a task, and miners are rewarded for resolving, for instance, a difficult mathematical puzzle. These complicated mathematical puzzles are not suitable for use in the real world due to their enormous energy consumption. On every occasion, the ledger is updated by any new deal, and the miners are required to resolve any issues, signifying the expenditure of a considerable amount of energy. An alternative to proof-of-work now being widely proposed is proof-of-stake. In this consensus mechanism, block validation is based on miners' stake. The miners earn a portion as compensation from the operation. A transaction proposing more significant compensation has a higher chance of being added quickly. This consensus mechanism does not consume as much energy as PoW consensus; however, it is more vulnerable as a hacker can return the transactions and bribe the miners to approve them. (d) Political Obstacles  
Handling political dissent, for instance, how to handle sensitive published content about public authorities, is a challenging task. When miners are institutionally constrained, they may well consider false propaganda that has been posted in aid of particular party to be true. As a result, it is tough to trace articles based on political ideologies by employing the Ethereum blockchain. Online services must face job risks when using factual authentication mechanisms, which may force them to compete for evaluations [33,52]. (e) Security of blockchains  
Blockchains can be safer than other systems. However, this does not signify that they are entirely safe. There are diverse methods by which a blockchain can be discredited. The safety of the blockchain itself requires being afraid. If a large portion of computing power is localized inside a specific group, individuals can target the blockchain and blockchain implementations, which is frequently referred to as a 51% attack [48]. After a successful attack, the attackers can change the stored content and obtain access to the personal information of users. (f) Newness of the system The popularity of blockchain-based social platforms may only be realized in ten or twenty years, as the technology is not mature at present. It is impossible to transplant the whole system that has formed on the basis of the scale of centralized social media to a decentralized platform. The main difficulty lies in dealing with the technology itself.