Here's a question for you. How much of the mail that comes to Microsoft is spam ? 50% ? Microsoft is a well know company and we publish a lot of our addresses, so its probably a bit worse than you'd expect... 60% ?
This morning I was doing an interviewing Tim Hynes about Microsoft Insight for the Tech-ed's Virtual side; insight grew out of IT showcase. By coincidence I'd had a mail with some interesting links in it and one of them was entitled "Messaging Hygiene at Microsoft: How Microsoft IT Defends Against Spam, Viruses, and E-Mail Attacks" How much spam then 70% ?
The paper has some statistics on Microsoft's network, which gives you some idea why Tim and his team are interesting people for any IT manager to talk to; we have
What do think then 80% of mail is dropped as spam ? Nearly. This is what the paper says
Connection filtering blocks approximately 80 percent of all incoming SMTP messages. But that's not the end of it; Sender and recipient filtering deletes 70 percent of the messages received after connection filtering.
That's 94% then Intelligent Message Filter rejects 6 percent of the remaining incoming messages as spam. The Anti-Virus processes the message..
On average, only about 5 percent of the total daily volume of incoming Internet e-mail remains
My mischievous side wonders what the Intelligent Message filter would make of a lot the internal mail I receive.