However, SMTP and POP3 will probably not be the only protocol required to make the project fully functional. The one specific instance of another form of communication is Public Key Distribution. The Public Key Server will use its own protocol to transmit and verify Public Keys. (see Public Key Server)

It is possible that the Open Source system called Jabber will be used for some functions. Jabber is an instant messaging system. It could be used to hold public keys, and to transmit XML Documents. Jabber has been developed around transmitting XML.

Emailed Documents themselves will be MIME attachments inside Emails. This way, even if a non Internet Document mail reader receives an email, the attached file could be saved and later imported into a Internet Document Accounting System. Documents transmitted by Jabber will be encrypted and included inside an XML tag.