How can domain diversification act as a reputation firewall?

Separation strategy:

• Transactional on main domain
• Marketing on subdomain
• Cold outreach on separate domain
• Risky activities fully isolated

Firewall benefits:

• Marketing problems do not affect transactional
• Experiments do not risk main reputation
• Can sacrifice isolated domains if needed

Implementation:

• Proper authentication per domain
• Clear routing rules
• Separate IP pools if possible
• Documentation of domain purposes
• Isolation protects your most valuable sending assets.

Damage control: compartmentalization prevents one problem from sinking everything.