What are the security implications of using DnsMailClient?

Hello,

I see in the latest version of Aspose.Network the DnsMailClient class, which looks interesting to me. I’m a bit confused about a fundamental concept, though. If DnsMailClient sends a message through the recipient’s mail server (without going through my own SMTP server), wouldn’t the target server have security controls in place to prevent this?

DnsMailClient is not sending an email message to the recipient's mail server actually. It just works as a normal email exchange process. Like what the emails exchange between smtp servers.