All You Need to Know About E-mail Authentication

Very soon, however, e-mail authentication may be more than just best practices; it may be a necessary process in order to clear ISP gatekeepers. If you don’t authenticate your e-mail, it may not be delivered.

In October 2005, the DMA passed an ethics guideline requiring members to authenticate their outgoing e-mails. The guideline, which went into effect Feb. 1, 2006, states: “Marketers that use e-mail for communication and transaction purposes should adopt and use identification and authentication protocols.” It’s designed to protect brands against illegal use and reduce false positives, while decreasing deliverability.
How to Authenticate
E-mail authentication is easy to do and there are several interoperable and inexpensive ways to do it. There currently are two major types of interoperable e-mail authentication systems: IP-based solutions like Sender Policy Framework (SPF) and Sender ID Framework (SIDF), as well as cryptographic solutions such as DomainKeys Identified Mail (DKIM).