07-19-2006 08:44 AM - edited 03-09-2019 03:38 PM
If a (PC) client sends a TCP SYN packet to a system using a destination TCP port 80..and that system is not listening on TCP port 80..does the system respond with some sort of TCP packet?
Thanks,
Mike
07-19-2006 04:48 PM
Hi,
If tcp 80 is not opened, the system will not give any respond or acknowledge the syn request.
Rgds,
AK
07-19-2006 08:42 PM
Hmmm....what about ICMP port unreachable??? :)
07-20-2006 09:14 AM
You should try it yourself using tcpdump or ethereal or whatever to capture the traffic. Different operating systems may behave differently. I believe the typical behaviour is to return a TCP rst...so the answer is yes.
07-20-2006 09:32 AM
Looks like Windows responds with RST-ACK.
Hope that helps!
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