Email Sender Reputation and Authentication

Email is one of the most popular and effective yet complex and frustrating methods of marketing used today. On the one hand, email marketing is cost effective, instantaneous and has the highest ROI of any type of digital marketing. On the other hand, email deliverability is unreliable and can be technically-challenging. Beyond the basics of good message, good design and email list validity / cleanliness, there are factors involved in the email delivery process that are beyond the sender’s control. That’s because an email does not go in a straight digital line from the sender’s outbox to the recipient’s inbox. Why? Well, it basically boils down to a fundamental flaw in the system. Traditional SMTP (email) servers were never designed to deliver bulk, outbound email. They were designed for individual emails. The primary workaround for bulk email, especially those that involve large lists, is batch deliveries and that causes delays and problems.

Even with batch deliveries, spikes in email volume raise red flags with major Internet Service Providers, such as Google, Yahoo!, Hotmail and AOL. Given that many of the emails sent on a daily basis could be classified as spam – in that they are sent in bulk and are unsolicited — ISPs created sophisticated systems to prevent overwhelming their networks. ISPs scrutinize every message that comes on the network and decide what to do based on certain characteristics. Sometimes this scrutiny gets in the way of legitimate email delivery. For that reason, it’s important to implement best practices that increase email deliverability. Last week, we examined such basics as improving email address collection practices, and cleaning existing email lists. We also examined a key practice of getting email permission from all contacts. Beyond the basics, there are some additional technical steps that can be taken to help with email deliverability. Here’s how.

There are two main components to email deliverability. One is infrastructure. The other is accreditation.

Infrastructure and Accreditation

Infrastructure involves putting certain things in place between the sending email server and the receiving email server that creates a trust mechanism between the two so that sent email is received more favorably.

Accreditation is the process of ensuring the receiving server can verify that the sender is who the sender says he/she/it is. There has been an explosion of “phishing” and “spoofing” emails. That is when a spammer hacks and steals the identity of a legitimate domain owner in order to get its email delivered. To avoid that, ISPs have mechanisms that prove that the email really has been sent by the party from which it is claiming to originate.

The responsibility for authentication is squarely on the shoulders of companies sending out their own emails. Here are some steps to implement authentication.

a. Register domains
Register a sub-domain or a custom domain specifically for email activity.
A sub-domain can then be linked to the broadcast server for SPF/Sender-ID needs.

b. Validate Sender-ID/Sender Policy Framework (SPF) record
Ensure that a Sender-ID/Sender Policy Framework (SPF) record is in place. This enables the receiving email server to carry out a lookup that validates whether the domain name that the email claims to represent is associated with the IP address from which the email was broadcast. If this test fails, the email is rejected.

c. Use Domain Keys Identified Mail (DKIM) and Domain Keys
Ensure that Domain Keys Identified Mail (DKIM) and Domain Keys are being used. This builds on Sender-ID/SPF, which validates the email’s delivery path, by going one step further and authenticating each email message. This is done by including a signature key which is generated by the sender and included within the email header. The receiving email server will accept the email if it can successfully decode the key.

Monitor Sender Reputation

A company’s ‘Sender Reputation’ is the single most important factor used to determine email acceptance by an Internet Service Provider. In other words, email sent by a sender with a good reputation gets delivered and email sent by a sender that has a bad reputation (and/or is blacklisted) bounces.

A sender’s reputation is monitored by a variety of factors and is linked either to the domain or the IP address from which the emails are sent or a combination of both.
ISPs often use external companies to provide sender reputation data so that they can screen emails against it. Many of these suppliers of sender reputation offer lookup facilities where users can enter an IP address and get a free report of their current sender reputation status. If a sender has a bad reputation, it is important to implement best practices in order to improve that score.

Some may think that if an IP address has a bad reputation, then perhaps it is easier to just kill that IP address and start fresh with a new one. Thank again. If a sender deploys a new IP address, initially at least that new IP address will not have a reputation score associated with it. The score builds as activity is tracked and metrics constructed. It is commonly held that the only thing worse than a poor reputation score is to have no reputation score at all. ISPs don’t like surprises, and to be hit with a large volume of email volume from a previously unknown IP address is almost certainly going to result in the eblast getting blocked by one or more of the major ISPs.

Avoid IP Addresses for Links

Don’t use an IP address in links to pages or images. This is something that phishers and spammers often do. For example, a link should not look like: http://193.241.33.1/page/.
This causes some ISPs to disable the links and label it as spam.

Seed Lists

To see if a particular email is likely to get delivered, a sender can use a seeded test list to check deliverability. A seeded list is comprised of inhouse Gmail, Hotmail, Yahoo! and AOL email addresses (at least 10 per ISP) that are controlled by the sender. The sender then test sends an email to those internal email addresses to see if the email gets delivered.

Provide unsubscribe links and instructions

Every email should contain unsubscribe instructions by law. Carefully word the unsubscribe offer so it doesn’t look like that commonly used by spammers. A statement of origination should explain either that the recipient has either opted in or is receiving the email since he/she is an existing customer. Also put the company name, address, registration number, contact details in the email footer. This is a legal requirement in many countries and considered a best practice by all legitimate email vendors.

There are many more tips and steps to ensure maximum email deliverability. Often the easiest approach for small to mid-sized companies is to use a reputable vendor for email deployment and monitoring. Whether doing emails internally or using a vendor, it is important to implement best practices and stay abreast of changes in email practices to ensure that this most valuable marketing tool is most effective.

Quote of the Week

“The first rule of any technology used in a business is that automation applied to an efficient operation will magnify the efficiency. The second is that automation applied to an inefficient operation will magnify the inefficiency.” Bill Gates

© 2014, Keren Peters-Atkinson. All rights reserved.