How EPA Works - The Software Engineer's Explanation

Purpose

EPA exists to apply mailbox-owner-specified criteria to filter and classify an e-mail as a necessary prelude to defining subsequent processing actions.

Basic EPA Functionality

1. Enable the mailbox owner to define filtering criteria and associated post-classification processing.
2. Interact with the domain mail server to access and inspect arriving e-mails.
3. Apply a mailbox owner's specified criteria to e-mail content to filter and classify the e-mail.
4. Explain the classification by identifying the criteria that was satisfied.
5. Retrieve and report post-classification processing selected.
6. Maintain Mailbox Traffic Log and Domain Traffic Log to reflect processing operations.

Please read the Process Origins, the Design Objectives and the Design Considerations sections before proceeding to the more detailed proccess documentation.

EPA Process Components

The components underlying EPA's operations consist of two asynchronous software processes and multiple instances of a single data structure that's used for intra-process communication:

1. The data structure - an EPA Preference Set - contains definitions of the criteria and options specified by a mailbox owner to govern processing of the e-mail traffic through the mailbox. A single Preference Set can govern the EPA processing of any number - from one to all - of a domain's mailboxes. A domain mailbox with no associated Preference Set is not subjected to EPA processing.

2. The first software process - the EPA Window Clerk - provides the e-mail user or e-mail administrator with continuing online access to mailbox-associated:
   • Preference Sets to edit sets to reflect current desires and requirements.
   • Operation Records to monitor e-mail processing operations.

3. The second software process - the EPA Mail Clerk - operates at OSI Level 6 as an extension of the domain's e-mail server Mail Transfer Agent(s) (MTA(s)) or functional analogues thereof during server e-mail acquisition and transmission to:
   1. Interface and coordinate operations with the domain e-mail server software's operational flow.
   2. Classify and direct the onward processing of e-mail based on the content of the Preference Set associated with the e-mail.
      
   3. Maintain the EPA Operations Records, including:
      • Mailbox Mail Traffic Log - that records all processing actions taken for every mailbox e-mail.
      • Domain Mail Traffic Log - that records all processing actions taken for every domain e-mail.
      • Mailbox Preferences Set History - that records successive changes in Preference Set content.

In the e-mail operational environment, the functional component configuration and data flows are...
... and where the E-mail Client software may employ Internet, LAN or hardwired access.