[dns-operations] ``Ya.com says "The internet is mine" ''

Peter Dambier peter at peter-dambier.de
Wed Aug 9 08:23:43 UTC 2006

Rick Jones wrote:
> I wonder what would happen if a helpful TCP stack, upon recieving a SYN 
> segment destined to a port without an active LISTEN endpoint decided to 
> complete the connection anyway to send-back some sort of helpful - "Did 
> you really mean to connect to port <mumble>?" rather than a RST or 
> silence?  Or better still, a UDP datagram arriving for a port without an 
> open socket?

ICMP does exactly that since the beginning of the internet.

If you have an ICMP listener running you will see things like


Those messages could indeed help you but the makers of many routers think
ICMP messages are dangerous and will only help hackers and endusers dont
know what to do with them. That is why many have disabled them and now
are bussy reinventing the wheel.

Peter and Karin

Peter and Karin Dambier
Cesidian Root - Radice Cesidiana
Graeffstrasse 14
D-64646 Heppenheim
+49(6252)671-788 (Telekom)
+49(179)108-3978 (O2 Genion)
+49(6252)750-308 (VoIP: sipgate.de)
mail: peter at peter-dambier.de
mail: peter at echnaton.serveftp.com

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