ICMP - Destination Unreachable Message Analysis
www.firewall.cx › networking-topics › protocolsDec 26, 2021 · The ICMP - Destination host unreachable message is one which a user would usually get from the remote gateway when the destination host is unreachable. If, in the destination host, the IP module cannot deliver the packet because the indicated protocol module or process port is not active, the destination host may send an ICMP destination protocol / port unreachable message to the source host.