# A Survey on Blockchain-Based Search Engines
## 6 Discussion  
Conventional search engines have several problems, such as privacy violations and monopoly. Considering the blockchain's popularity and capabilities, such as distribution and cryptography, this technology can solve these problems. The blockchain is used in cloud computing, smart grid, and messaging systems to solve privacy and security issues. Additionally, it is used in file sharing and grid computing to solve problems such as access control, data integrity, and visibility related to monopoly. Using the blockchain as the primary approach in developing search results in powerful search capabilities that solve the mentioned problems. In the following, for better discussion, some critical questions have been answered.  
* Q1: What are the benefits of integrating blockchain and search engines technologies?
* Give users control of their data and the ability to share it selectively to protect user privacy;
* Disrupt the existing ad network, which is monopolized by large companies and dominated by middlemen, and create a competitive market that benefits all;
* Enable scalable, secure, and anonymous search over massive datasets;
* Allow everyone the opportunity of seeing the search results;
* Enable users to profit from their actions--whether or not personal information is revealed, searches create tokens for the searching user;
* Allow everyone to benefit significantly from decentralized collaboration;
* Eliminate the need for intermediaries by allowing direct customer-to-business interactions;
* Provide the context-aware and privacy-preserved search results in smart environments.
* Q2: What are the future dynamics of research in the blockchain-based search engines arena?  
As a future dynamic of research in this area, we may refer to possible combinations among search engine technology with digital twins, digital money, and IoT. Merging digital money platforms such as those reported in the blockchain technology domain with search engines might be the first substantial evolution of search technologies in the era of digital transformation. For example, blockchain-based search systems might be customized for IoT to bring a powerful search considering IoT's security and privacy issues.  
* Q3: Why do we need blockchain-based search engines?  
It is worth noting that the computational power of computers of the users increases day by day, and therefore, we must design efficient distributed search systems considering this potential. All the distributed search engines, such as blockchain-based technology, are not widespread for the users. This is because some of them attempt to save a centralized control. In other words, search engines may manipulate the results according to some arguments. On the other hand, decentralized architecture will be eliminated by decentralized architectures such as blockchain because the users prefer to utilize those technologies that protect their privacy.  
* Q4: What development hurdles can we face while shifting from centralized to distributed?As the main development hurdles that we can face while shifting from existing search ecosystems to blockchain-based ecosystems, blockchain infrastructures are costly. Therefore, the development of search systems based on them may lead to complex tasks.
* Q5: Who can welcome such search engines, and why is there a need for blockchain-based search engines, to name a few?  
Appearing in a blockchain-based search system can lead to an important phenomenon during digital transformation that may involve many new users and critical participants in search ecosystems. Presearch projects [15] prove the benefits of these systems for the users. Every user that has high activity in search space can obtain a valuable token. In other words, the economic cycle of the search system will not be restricted to a company or government.