Spam Curtailment
Since CIT implemented PureMessage to identify probable spam, we've found that more than 1,250,000 messages per day (Yes! More than a million every day. The mind boggles.) have been marked as probable spam at the 80%+ level. This represents about 80% of the total message traffic!
On February 1, 2005, we began rejecting these messages BEFORE they could enter the Cornell e-mail servers.
Rejecting these message means:
- traffic on the Cornell network is significantly decreased
- individual users can spend less time searching for important messages hiding among the junk mail
- individual users are able to store more (valid) messages on the e-mail servers
Rejecting these messages does NOT:
- generate more e-mail traffic
(the rejection is a message to the sender's e-mail server, similar to acknowledging successful transfer or "no such user" codes) - confirm nor deny the existence of the intended recipient's address
- tell spammers how to fool our system
The rejection code returned to the sender's ISP includes a URL (web address) where the sender can go for more information. Please note that it is up to the system that sent the message how this information is conveyed back to the individual sender. Most systems will generate an error message for their user which will include our URL so legitimate users can find another way to get through to you. It is our experience that the occurrence of false positive ratings at the 80% level are extremely rare. Nonetheless, we want to ensure that the sender of a false positive has the best possible chance to know that the message was not received, why, and what to do about it.
Note that this spam curtailment measure only applies to mail handled by CIT's e-mail infrastructure, that is, messages addressed to something@cornell.edu addresses. This includes mail delivered to CIT postoffices, and mail forwarded by our e-mail routers. Mail addressed directly to something@dept.cornell.edu is not handled by our e-mail routers, and will continue to be untouched by PureMessage. (How do I know if my mail is being checked?)
We believe that all users will find this spam blocking to be a good thing, so when we implemented this measure everyone was included. However, we recognize that some people may want to opt out, so we have created a means for people to do so. Anyone who opts out will continue to receive all messages. To change your opt-out status:
- Go to whoiam.cornell.edu.
- Click on the Electronic Mail link.
- Scroll down to the section labeled Spam Blocking.
- Put a check in the box to opt out, or clear the check to opt back in.
- Remember to click the Set it! button at the bottom of the page.
You can opt in or opt out at any time; the list of people who have opted out will be updated every night, so you'll see the effects beginning the next day.