Re: SMTP Port Blocking: Success or Failure?

On Sat, 26 Feb 2005, Claydon, Tom wrote:

We are considering filtering outbound SMTP traffic from our ISP customers, except from our own mail servers, to help reduce the amount of spam originating from our network. How successful/unsucessful has implementing outbound SMTP filtering done in stopping or slowing down spam from your network?

If you mean on Dial customers this sort of thing has been very helpful, add (as the previous conversations on this have shown, outbound to the dial user filters permitting source port 25 from your mail complex alone as well.