Hotmail Reduces Spam by 90%, Spam As a Whole is Now 15% Less on the Internet

Microsoft is touting the work it's doing about spam, acknowledging the dismal record Hotmail had recorded back in 2006, and the damage that all that unfiltered spam did to its reputation. Fast forward five years, and Hotmail has made significant progress, reducing the level of spam in the inbox by 90% since 2006, and reducing […]

Microsoft is touting the work it's doing about spam, acknowledging the dismal record Hotmail had recorded back in 2006, and the damage that all that unfiltered spam did to its reputation. Fast forward five years, and Hotmail has made significant progress, reducing the level of spam in the inbox by 90% since 2006, and reducing what was left another 40% just since last year.

The above chart shows two things:

  • Hotmail keeps spam out of your Inbox
    "We've reduced the level of spam in Hotmail by 90% since its peak in 2006. Since last year, we've reduced what was left by another 40% (from 5% true SITI to 3% true SITI)."
  • We've helped to reduce overall spam on the Internet
    "The percentage of spam on the Internet has actually declined 15% from its peak in 2008, due to a number of factors including the legal and technical disruptive action Microsoft has helped drive in the prosecution of spammers and the takedowns of botnets used to send spam. Botnets - collections of people's malware-infected computers covertly operating under the remote control of a cybercriminal - are often used to send spam (and commit other online crimes)," said Dick Craddock in a blog post on Hotmail spam on the Inside Windows Live blog.

The video below explains a little more about how botnets are used to send spam:

The follwing two tools augment the efficiency of our SmartScreen filters. Craddock said, "In addition, we're also continuously tuning the other SmartScreen features - like Time Travelling filter, IP reputation, URL reputation and more."

  • Personalization spam filters work based on how you use email - using information about the people you send email to and receive it from and also which email messages you actually read.
  • Trusted sender feature helps you visually identify senders in your inbox, with safety logos next to only those senders that we recognize as legitimate so that you can more easily spot malicious imitators.
  • "We've also made it increasingly difficult for the spammers to use Hotmail as a spam-sending tool. In fact, over the last year, we've reduced the volume of outbound spam from Hotmail by 75%," Craddock wrote. The following features helped us get it done:
    • Account reputation: As you use your account, you gain a "reputation." Good behavior (receiving email from the same people you sent email to, for example) gains you a good reputation. Bad behavior (sending a bunch of email and getting only delivery errors, for example) gains you a bad reputation, as these behaviors are indicative of spammers and other service abusers.
    • Account creation limits: To prevent spammers from getting an unlimited number of free accounts to use in sending spam -- we limit the number of accounts that can be created per day from a particular IP address.
    • Outbound content filters: Just like incoming mail filters to remove spam, we now filter outbound mail as well.
    • Spam and compromised accounts: Spammers are now hijacking your reputation as a good customer of Hotmail. How? By hijacking your account. In fact, most outbound spam now comes from hijacked accounts.

[Source: Inside Windows Live]