In this section, we sketch the design of a serverless email system, ePOST, on top of the POST infrastructure. The goal is to show how POST can support a secure, scalable and highly resilient email system that leverages the resources of participating desktop computers.
While a system like ePOST promises increased resilience, greater scalability and lower cost, it remains an open question whether these advantages will be sufficient to completely displace the existing, server-based email infrastructure. Nevertheless, we chose to pursue ePOST for several reasons.
First, ePOST is designed so that it can be deployed incrementally, thus allowing individual organizations to adopt it while still relying on existing standards and infrastructure for communication across organizations. Second, unlike most existing p2p applications, email is mission-critical and demands high reliability, security, and availability. Thus, it is a challenging driver for the development of POST and, more generally, the underlying p2p infrastructure.