[teddyh]

> SMTP is push, not polling.

Yes. And if you want to poll, POP is polling, and IMAP has both polling and immediate notifications.

[salamander014]

Yes, but SMTP is a protocol wherein a system opens a connection to another system and says, hey here's a message.

And if that doesn't succeed for some reason, it reliably queues and retries.

That's a push.

[teddyh]

I was not disagreeing, merely providing additional information. I have edited to clarify.