What is Challange/Response Filtering ?
Thursday, August 06, 2009 - 12:07 - Support
Challenge
/ Response filtering (C/R) is a very simple way of making sure senders
of emails do actually exists. The basic flow is:
1. A local recipient signs up to the service.
2.
When someone sends an email to the recipient, if they have not already
authenticated their email is placed into a holding area.
3. A authentication email is sent to the sender which includes an authentication key, to which they have to reply.
4.
When the sender replies sending the authentication key, their email
address is mapped to the original recipients email address and no
further authentication is required.
5. The original email is also released from the holding area when the sender has authenticated.
6. Authenticated users still have to pass all other filtering configurations once they have authenticated.
That's it in a nutshell.