Most spam comes from Chinese and Korean IP addresses, but the amount via Polish and French ISPs is close behind, according to security vendor Trend Micro.
Trend’s Dave Rand said ISPs should do more to prevent spam leaving their networks, and should help users by monitoring IP traffic from their PCs and helping them deal with problems caused by trojan horse software. He added that over 80 percent of spam now comes from PCs infected by software that allows unauthorised users to have remote control.
ISPs should block mail from dynamic IP addresses destined for a server using the TCP/IP port 25, said Rand. He added that this port should be used only by proper mail servers with static IP addresses, so such blocking should not affect legitimate email traffic.
ISPs urged to block spam
By Roger Howorth on Jul 11, 2006 2:10PM