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Lwip netmap
Lwip netmap











lwip netmap

You can list your UDP listenning ports in a linux system with: $sudo netstat -anlpuĪctive Internet connections (servers and established) Some services do indeed answer to TCP and UDP ports at the same time, as is the case of DNS and NTP services, however that is not certainly the case with web servers, which normally only answer by default to port 80/TCP (and do not work/listen at all in UDP) TCP/IP model and both have a very different usage. Both TCP and UDP work at the transport layer Transmission Control Protocol (TCP) and User Datagram Protocol (UDP) are How is that possible ? My port 80 is open, how come that Debian answers with an ICMP : Port unreachable error ? Is that a security issue?Īlbeit TCP and UDP are part of TCP/IP, both belong to the same TCP/IP or OSI layers, and both are a layer above IP, they are different protocols.

lwip netmap

Nmap done: 1 IP address (1 host up) scanned in 0.52 seconds Nmap done: 1 IP address (1 host up) scanned in 0.51 secondsīut when running UDP port scan, it fails and my Debian server answers with an ICMP : Port unreachable error : nmap -sU -p 80 192.168.1.166

#Lwip netmap mac

MAC Address: xx:xx:xx:xx:xx:xx (Cadmus Computer Systems) My Debian is a Virtual Machine running on a bridged connection.Ĭlassic port scanning using TCP SYN request works fine and detects port 80 as open (which is correct) : nmap -p 80 192.168.1.166 I am testing my Debian Server with some Nmap port Scanning.













Lwip netmap