IIS has an SMTP service.
I came back to this answer to be of more use. To be sure, the above answer is tongue in cheek.
If you're going to send out massive amounts of email, then you'd better know what you're doing and have some serious protective infrastructure. You need to set up SPF records and use DKIM. You'll want a bank of dedicated IP addresses for your outbound email. You'll need statistics and monitoring that are tracked within your emails to determine who is viewing what and if the email is truly wanted or not. You'll need double-opt in systems and on and on.
In short, if by "massive" you mean "millions of emails per day" or even just "hundreds of thousands per day" you'll need to lay out some serious cash and have some serious skills. You cannot use IIS's SMTP service for this. I repeat, you cannot use IIS for this. There is someone on this site that uses IIS to send hundreds of thousands of emails and it is not pretty. They are constantly black listed. They have a hard time managing it. They are consistently asking questions on ServerFault relating to their woes.
You will need to look into some software like PowerMTA to do all that you require. In fact, what would be better is if you use something like MailChimp or Constant Contact. If you have to send the mail yourself, look into companies like SendGrid or JangoMail that know how to handle outbound mail on a massive scale. Please don't do this yourself unless you have a crack engineering team (or your engineering team is on crack).