Security describes confidentiality, truthfulness, and availability, which are challenging tasks in public blockchains where keys are visible to all nodes. The confidentiality level is low in scattered systems, and truthfulness is the profession of blockchains; even though it faces different issues, blockchain accessibility is high in legibility compared to writing accessibility.

The following text is from the paper “Building Networked Security Mechanisms for Blockchains” (2017) by David Lang, Ran Canetti, Dan Boneh, and Arit Naor.”One distinguishing virtue of blockchains is that every node on the network can maintain a complete copy of the blockchain database and verify its validity.

“This is not only a liability for the system but also a significant design challenge.”The following text is from the paper “Building Networked Security Mechanisms for Blockchains” (2017) by David Lang, Ran Canetti, Dan Boneh, and Arit Naor.”One distinguishing virtue of blockchains is that every node on the network can maintain a complete copy of the blockchain database and verify its validity.”This is not only a liability for the system, but also a significant design challenge.”The following text is from the paper “Building Networked Security Mechanisms for Blockchains” (2017) by David Lang, Ran Canetti, Dan Boneh, and Arit Naor.

“One distinguishing virtue of blockchains is that they make building and running a trustless system much easier. However, the existence of a trusted entity can still optionally be used to achieve some efficiency or convenience.”
“Trustlessness in blockchains comes with its challenges: how do you design mechanisms that offer the benefits of trustlessness while remaining trustable? How do you incentivize nodes to participate in consensus and ensure that the system remains decentralized?”
They say, “Removing intermediaries is not enough.”Our comment: This is just normal economics. We want to remove intermediaries because they are a cost, but in order to make it happen, we need to replace them with something that can offer the same service to consumers at a lower cost.