The role of service provider is like that of printer and distributor in the paper world. The publisher contracts with the service provider for the material to be reproduced and distributed, just as the publisher now does in the paper world. In our model, the unit of sale can be as small as one byte. Note, of course, that these roles may overlap. In the network community we anticipate a customer will often be both author and publisher, as well.
Nothing is sent but what the reader asks for.
The customer pays on a per-byte basis for all published materials sent by the server. The publisher contracts with the service provider for the storage of the document and its sale by arbitrarily small fragment. The service provider promises to send the royalties for each sent byte. The service provider also agrees to forward materials to other service providers as needed to provide the service throughout the network. These same understandings ordinarily hold in paper publishing, but are not made explicit.