Quote:
Originally Posted by BlackCrayon
Its pretty easy to set it up so non existant users don't accept mail.
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Right, but consider the volume. 500 million attempts per day is 5787 new connections per second, which is certainly excessive for a customer base that size. Handling that level of connections would not be easy for a single server. In addition, if each SMTP transaction uses about 1k of transfer back and forth then you're looking at 5.8Mbytes/sec or an additional 46Mbit/sec worth of bandwidth just to respond to this garbage. In 2003 this level of bandwidth wouldn't have come cheap, particularly considering that the spamming was providing zero value add to the company and its customers.
Back of the envelope calcs...
5000 customers, let's assume they're all dialup
10:1 modem ratio, which means 500 modems @56kbps theoretical max transfer
500 x 56kbps = a mere 28Mbit/sec of MAXIMUM bandwidth used... but the above figure for accepting spams would be AVERAGE...
Now do you see how drastically it could have affected their business? Imagine having to pay 3 times as much for your bw just because one third party asshole decides he's going to mail your customers.