Port 1751 (swiftnet)

IANA assigns port 1751 to swiftnet: SwiftNet.

Registered (user) port, 1024-49151 TCPUDP

IANA assignment

Service nameProtoDescriptionAssigneeReference

swiftnet TCP SwiftNet Terry Lim -

swiftnet UDP SwiftNet Terry Lim -

Linux: is anything listening on TCP 1751?

sudo ss -tlnp 'sport = :1751'

Linux: UDP 1751

sudo ss -ulnp 'sport = :1751'

Linux / macOS: which process owns the port

sudo lsof -nP -i :1751

Older Linux / BSD (net-tools)

sudo netstat -tlnp | grep ':1751 '

Windows (Command Prompt)

netstat -ano | findstr :1751

Windows (PowerShell)

Get-NetTCPConnection -LocalPort 1751 -State Listen | Select LocalAddress,OwningProcess

From another machine

nc -vz -w 5 HOST 1751

From Windows

Test-NetConnection HOST -Port 1751

UDP probe (no reply does not prove it is closed)

nc -vzu -w 5 HOST 1751

ufw

sudo ufw deny 1751/tcp

iptables

sudo iptables -A INPUT -p tcp --dport 1751 -j DROP

nftables

sudo nft add rule inet filter input tcp dport 1751 drop

Windows Firewall

New-NetFirewallRule -DisplayName 'Block TCP 1751' -Direction Inbound -Protocol TCP -LocalPort 1751 -Action Block

ufw

sudo ufw deny 1751/udp

iptables

sudo iptables -A INPUT -p udp --dport 1751 -j DROP

nftables

sudo nft add rule inet filter input udp dport 1751 drop

Windows Firewall

New-NetFirewallRule -DisplayName 'Block UDP 1751' -Direction Inbound -Protocol UDP -LocalPort 1751 -Action Block

All port numbers · Open port checker
Assignment data: IANA port number registry (public domain), retrieved 2026-11-10.