We contracted with a 3rd party vendor to build and host a web application for us. The web app will need to send email notifications out to users when they request it. The application is not hosted on our network, but it is reachable via a sub-domain we set up.
What options exist for sending the email? I know that we could have the application connect to the SMTP servers on our network and send the messages from an account setup there.
Is it possible to send the messages from the externally hosted server and not have them get eaten by every spam filter on the net? Would setting up SPF, Domainkeys, and/or DKIM address this? And if so, would it be just a good as sending the messages through the SMTP servers on our network?