Email Infrastructure Basics for Better Deliverability

Email deliverability is a critical aspect of any successful email marketing campaign. Understanding the technical infrastructure behind email sending is essential for ensuring your messages reach your subscribers' inboxes. In this comprehensive guide, we'll dive deep into the fundamentals of email infrastructure, exploring the key components, best practices, and common pitfalls to avoid. By the end, you'll have a solid foundation for optimizing your email setup and achieving better deliverability.

The Email Sending Process

Before we delve into the specifics of email infrastructure, let's first understand the basic process of sending an email. When you hit "send" on an email, it goes through several steps to reach the recipient's inbox:

1. Your email client or server connects to the SMTP server and submits the email.
2. The SMTP server performs initial checks (e.g., spam filtering, authentication) and routes the email to the recipient's mail server.
3. The recipient's mail server receives the email and stores it in the appropriate mailbox.
4. The recipient's email client retrieves the email from the mailbox and displays it in their inbox.

Understanding this basic flow is crucial for identifying potential issues and optimizing your email infrastructure for better deliverability.

Key Components of Email Infrastructure

Several key components work together to ensure the smooth functioning of your email infrastructure. Let's explore each of these in detail:

1. Email Service Provider (ESP)

An Email Service Provider (ESP) is a company that provides email marketing services, allowing you to send bulk emails to your subscribers. ESPs typically offer features such as email template design, list management, and analytics. Some popular ESPs include:

• Mailchimp
• Constant Contact
• Campaign Monitor
• SendGrid
• ActiveCampaign

2. SMTP Server

Simple Mail Transfer Protocol (SMTP) is the standard protocol used for sending emails across the internet. An SMTP server is responsible for handling the outgoing email traffic from your ESP or email client. It communicates with the recipient's mail server to deliver the email.

When setting up your email infrastructure, you have two options for SMTP servers:

• Shared SMTP Server: Most ESPs provide a shared SMTP server that you can use to send emails. This is a convenient option, especially for small to medium-sized businesses.
• Dedicated SMTP Server: For larger organizations with high email volume or specific security requirements, setting up a dedicated SMTP server can be beneficial. This gives you more control over your email sending infrastructure.

3. DNS Records

Domain Name System (DNS) records play a crucial role in email deliverability. They help establish your domain's reputation and authenticate your emails. The two main DNS records to focus on are:

• SPF (Sender Policy Framework): SPF is a DNS record that specifies which IP addresses or servers are allowed to send emails on behalf of your domain. It helps prevent spammers from spoofing your domain.
• DKIM (DomainKeys Identified Mail): DKIM is a digital signature that verifies the authenticity of an email. It ensures that the email hasn't been tampered with during transit and helps establish trust with the recipient's mail server.

4. IP Reputation

Your sending IP address's reputation is a critical factor in email deliverability. Mail servers use IP reputation to determine whether to accept or reject incoming emails. Factors that affect your IP reputation include:

• Spam complaints
• Hard bounces
• Sending volume consistency
• Engagement rates (opens, clicks)
• Presence on blacklists

To maintain a good IP reputation:

1. Warm up your IP gradually by sending low volumes initially and slowly increasing over time.
2. Maintain consistent sending volumes to establish a reliable pattern.
3. Monitor your email metrics and address any issues promptly.
4. Use a dedicated IP address for high-volume sending.

Email Authentication Protocols

In addition to SPF and DKIM, there are other authentication protocols that contribute to email deliverability:

1. DMARC (Domain-based Message Authentication, Reporting, and Conformance)

DMARC is an email authentication protocol that builds upon SPF and DKIM. It allows domain owners to specify how receiving mail servers should handle emails that fail SPF and DKIM checks. DMARC also provides a reporting mechanism to monitor email traffic and identify potential issues.

To set up DMARC:

1. Publish a DMARC record in your DNS settings.
2. Specify your DMARC policy (none, quarantine, or reject).
3. Provide an email address for receiving DMARC reports.
4. Monitor DMARC reports and adjust your email infrastructure as needed.

2. BIMI (Brand Indicators for Message Identification)

BIMI is an emerging email standard that allows brands to display their logo next to authenticated emails in the recipient's inbox. By implementing BIMI, you can increase brand visibility and trust, leading to higher engagement rates.

To set up BIMI:

1. Ensure you have a valid DMARC policy in place.
2. Create a SVG version of your logo that meets the BIMI guidelines.
3. Host the logo on a secure server accessible via HTTPS.
4. Publish a BIMI record in your DNS settings, specifying the logo URL.

Best Practices for Email Infrastructure Setup

To optimize your email infrastructure for better deliverability, follow these best practices:

1. Use a Dedicated IP Address

If you send a high volume of emails, consider using a dedicated IP address instead of shared IPs. This gives you more control over your sender reputation and reduces the risk of being affected by other senders' actions.

2. Implement Proper Authentication

Set up SPF, DKIM, and DMARC authentication to establish trust and improve deliverability. Regularly monitor your authentication records and update them as needed.

3. Maintain Good List Hygiene

Regularly clean your email list by removing inactive, bounced, and unengaged subscribers. This helps maintain a healthy sender reputation and reduces the risk of spam complaints.

4. Monitor Email Metrics

Keep a close eye on your email metrics, such as open rates, click-through rates, and bounce rates. These metrics provide valuable insights into the health of your email program and can help identify potential issues early on.

5. Use Email Authentication Tools

Leverage email authentication tools to monitor and troubleshoot your email infrastructure. Some popular tools include:

• MxToolbox: Checks DNS records, blacklists, and SMTP server configuration.
• Google Postmaster Tools: Provides insights into your email performance and reputation in Gmail.
• Microsoft SNDS: Offers data on your email performance and reputation in Microsoft's email services.
• DMARC Analyzer: Helps monitor and troubleshoot DMARC implementation.

Troubleshooting Common Email Deliverability Issues

Despite following best practices, you may still encounter email deliverability issues. Here are some common problems and how to address them:

Email Infrastructure Success Stories

Many companies have successfully optimized their email infrastructure to achieve better deliverability and engagement. Here are a few success stories: