3 ms·

Same way Google broke SMTP. Even SPF isn't enough anymore.

• LeonM 3y ago
  > Even SPF isn't enough anymore. SPF is a old and horribly broken standard, and should not be relied on for at least 10 years now. DKIM and DMARC is the way to go for outbound SMTP. Google didn't break SMTP, spammers did.
  • pixl97 3y ago
    Heh, so many anti-https people here that seem clueless the internet is not a safe place. There is always someone out there looking to exploit you on the net.
• jeroenhd 3y ago
  SPF was a bandaid on a flesh wound. SPF+DKIM+reverse PTR(+DMARC unless you like discovering your email hasn't been arriving for months) are almost good enough (except that DKIM doesn't sign the things you expect it to sign). Google and Microsoft still killed email with their unreliable spam filters, but SPF alone was never enough. SMTP still works fine though.
  • cutler 3y ago
    .... unless your mailserver's IP/network has been blacklisted by said behemoths.
    • LeonM 3y ago
      Given that you talk about 'even' implementing SPF, and now about IP blacklisting gives me the impression you haven't actually worked (or kept up with) email over the last 10 years. None of the major email service providers (or 'behemoths', as you call them) use IP blacklisting anymore. They abandoned that idea years ago. IP addresses are ephemeral, especially when IPv6 is used, so IP blacklisting simply does not work anymore. If we were to use IP based blacklisting we'd have blacklisted the entire IPv4 address space by now. Yes, like any other SMTP service they will block IP addresses momentarily if you misbehave, but never permanently. All major spam filters are content based, and reputation is always on the domain level, not IP level. If you properly configure your email infrastructure, and you don't spam, then deliverability really shouldn't be a problem.