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I think that the main problem is that the forum must be available to everyone and easy to use for beginners. If the group is closed or Nodes could have a firewall, this will reduce the features of the forum.
How large is the blockchain that the client needs, and how can shares be modified, deleted, does it require approval from all nodes, or can the user change it? Since there is no encryption/decryption, losing the private key or having another party know it means you need to create a new account, or is there a way to solve this problem?
I think that the main problem is that the forum must be available to everyone and easy to use for beginners. If the group is closed or Nodes could have a firewall, this will reduce the features of the forum.
How large is the blockchain that the client needs, and how can shares be modified, deleted, does it require approval from all nodes, or can the user change it? Since there is no encryption/decryption, losing the private key or having another party know it means you need to create a new account, or is there a way to solve this problem?