The last time I saw this kind of proposal, it was even simpler than this.
The work was defined as: Given the following salt, construct a payload such that a md5 hash of the salt and payload would result in a hash with n consecutive 0's.
Simple to implement on both ends, and fast enough to not impede much in the user experience but still expensive enough to limit spam. And it becomes easy to increase the work proof required - just increment 'n'.
The work was defined as: Given the following salt, construct a payload such that a md5 hash of the salt and payload would result in a hash with n consecutive 0's.
Simple to implement on both ends, and fast enough to not impede much in the user experience but still expensive enough to limit spam. And it becomes easy to increase the work proof required - just increment 'n'.