Simple Mail Transfer Protocol (SMTP) Question:

The InterStream Transit Protocol (ISTP) is a secure protocol that allows Internet Service Providers (ISPs) to offer high bandwidth multimedia services over their networks. The ISTP application is installed as a new protocol handler into browsers. It includes components which enable Internet Service Providers to obtain incremental revenue from subscribers, advertisers, other ISPs, and streaming video providers in exchange for using premium bandwidth services on their networks.