Dedicated vs Shared IP Address
Choosing between a dedicated and shared IP affects your sender reputation and warmup requirements. This guide compares both options with clear recommendations.
How Email Delivery Actually Works
The Journey of One Email
When you click Send Campaign in AcelleMail, a chain of events fires before the email reaches the inbox.
Step 1: The Queue
AcelleMail adds each recipient to a Laravel queue. Queue workers pick up jobs and hand them to your configured SMTP server (or local MTA like Postfix).
Step 2: DNS MX Lookup
Your MTA needs to find where to deliver the message. It queries DNS for the recipient domain's MX records:
dig MX gmail.com
# Returns: gmail-smtp-in.l.google.com (priority 5)
The MX record points to Google's receiving server.
Step 3: The SMTP Conversation
Your server opens a TCP connection on port 25 (or 587/465) to Google's server:
→ EHLO mail.yourdomain.com
← 250 mx.google.com at your service
→ MAIL FROM: <bounce@yourdomain.com>
← 250 OK
→ RCPT TO: <user@gmail.com>
← 250 OK
→ DATA
→ [email headers + body]
→ .
← 250 Message accepted
→ QUIT
Step 4: TLS Negotiation
Modern servers require STARTTLS or connect over port 465 (SMTPS). This encrypts the SMTP conversation, preventing eavesdropping in transit.
Step 5: Authentication Checks
The receiving server runs three checks:
- SPF — is the sending IP authorized by the From domain's SPF record?
- DKIM — is the DKIM signature in the headers valid?
- DMARC — do SPF and/or DKIM align with the From header domain?
All three must pass for the best inbox placement.
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View all →Email Queue Architecture in AcelleMail
Understand how AcelleMail breaks campaigns into queue jobs, processes them with workers, handles retries, and tracks delivery status.
Dedicated vs Shared IP Address
Choosing between a dedicated and shared IP affects your sender reputation and warmup requirements. This guide compares both options with clear recommendations.
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