How do corporate/enterprise filters behave differently from consumer ISPs?

Corporate versus consumer filter differences:

Corporate/enterprise filters:

Barracuda, Proofpoint, Mimecast, Microsoft Defender

Often more aggressive blocking

Policy-based rules (no marketing from unknown senders)

Less engagement-based, more rule-based

Company-specific configurations

Consumer ISPs:

Gmail, Yahoo, Outlook.com

More engagement and reputation focused

ML-based filtering

More uniform behavior across users

Implications:

B2B mail faces different challenges than B2C

Good consumer reputation does not guarantee corporate delivery

Corporate filters may need direct relationship or whitelisting

Commercial ports have different inspection standards than private harbors.