IANA assigns port 1657 to fujitsu-mmpdc.
sudo ss -tlnp 'sport = :1657'sudo ss -ulnp 'sport = :1657'sudo lsof -nP -i :1657sudo netstat -tlnp | grep ':1657 'netstat -ano | findstr :1657Get-NetTCPConnection -LocalPort 1657 -State Listen | Select LocalAddress,OwningProcessnc -vz -w 5 HOST 1657Test-NetConnection HOST -Port 1657nc -vzu -w 5 HOST 1657sudo ufw deny 1657/tcpsudo iptables -A INPUT -p tcp --dport 1657 -j DROPsudo nft add rule inet filter input tcp dport 1657 dropNew-NetFirewallRule -DisplayName 'Block TCP 1657' -Direction Inbound -Protocol TCP -LocalPort 1657 -Action Blocksudo ufw deny 1657/udpsudo iptables -A INPUT -p udp --dport 1657 -j DROPsudo nft add rule inet filter input udp dport 1657 dropNew-NetFirewallRule -DisplayName 'Block UDP 1657' -Direction Inbound -Protocol UDP -LocalPort 1657 -Action BlockAll port numbers · Open port checker
Assignment data: IANA port number registry (public domain), retrieved 2026-11-10.