What’s the difference between link CNAME and email sending domain?

Two separate domain configurations:

Sending domain:

Appears in your From address (captain@tidalmail.com)

Requires SPF, DKIM, DMARC authentication

Subject to reputation scoring

Affects inbox placement directly

Link tracking domain:

Appears in URLs within email content

Configured via CNAME to ESP tracking servers

Requires valid SSL certificate

Affects link reputation and click trust

Both matter for deliverability. A great sending domain with suspicious-looking links still triggers filters. Professional setup includes both.

Different credentials: who sent the cargo versus whose packaging it arrives in.