IANA assigns port 1618 to skytelnet.
sudo ss -tlnp 'sport = :1618'sudo ss -ulnp 'sport = :1618'sudo lsof -nP -i :1618sudo netstat -tlnp | grep ':1618 'netstat -ano | findstr :1618Get-NetTCPConnection -LocalPort 1618 -State Listen | Select LocalAddress,OwningProcessnc -vz -w 5 HOST 1618Test-NetConnection HOST -Port 1618nc -vzu -w 5 HOST 1618sudo ufw deny 1618/tcpsudo iptables -A INPUT -p tcp --dport 1618 -j DROPsudo nft add rule inet filter input tcp dport 1618 dropNew-NetFirewallRule -DisplayName 'Block TCP 1618' -Direction Inbound -Protocol TCP -LocalPort 1618 -Action Blocksudo ufw deny 1618/udpsudo iptables -A INPUT -p udp --dport 1618 -j DROPsudo nft add rule inet filter input udp dport 1618 dropNew-NetFirewallRule -DisplayName 'Block UDP 1618' -Direction Inbound -Protocol UDP -LocalPort 1618 -Action BlockAll port numbers · Open port checker
Assignment data: IANA port number registry (public domain), retrieved 2026-11-10.