We now examine issues of trust in some popular file-sharing and anonymous publishing systems.
Many of the publishing systems described in this book rely on a collection of independently owned servers that volunteer disk space. As disk space is a limited resource, it is important to protect it from abuse. CPU-based payment schemes and quotas, both of which we mentioned previously, are possible deterrents to denial of service attacks, but other methods exist.
Mojo Nation uses a digital currency system called Mojo that must be paid before one can publish a file on a server. In order to publish or retrieve files in the Mojo Nation network, one must pay a certain amount of Mojo.
Mojo is obtained by performing a useful function in the Mojo Nation network. For example, you can earn Mojo by volunteering to host Mojo content on your server. Another way of earning Mojo is to run a search engine on your server that allows others to search for files on the Mojo Nation network.
The Free Haven project utilizes a trust network. Servers agree to store a document based on the trust relationship that exists between the publisher and the particular server. Trust relationships are developed over time and violations of trust are broadcast to other servers in the Free Haven network. Free Haven is described in Chapter 12.
Publius, Free Haven, and Mojo Nation all rely on volunteer disk space to store documents. All of these systems have ...