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Port 3457 (vat-control)

IANA assigns port 3457 to vat-control: VAT default control.

Registered (user) port, 1024-49151 TCPUDP

IANA assignment

Service nameProtoDescriptionAssigneeReference
vat-control TCP VAT default control Van Jacobson -
vat-control UDP VAT default control Van Jacobson -

Check what is listening on port 3457

Linux: is anything listening on TCP 3457?
sudo ss -tlnp 'sport = :3457'
Linux: UDP 3457
sudo ss -ulnp 'sport = :3457'
Linux / macOS: which process owns the port
sudo lsof -nP -i :3457
Older Linux / BSD (net-tools)
sudo netstat -tlnp | grep ':3457 '
Windows (Command Prompt)
netstat -ano | findstr :3457
Windows (PowerShell)
Get-NetTCPConnection -LocalPort 3457 -State Listen | Select LocalAddress,OwningProcess

Test it from outside

From another machine
nc -vz -w 5 HOST 3457
From Windows
Test-NetConnection HOST -Port 3457
UDP probe (no reply does not prove it is closed)
nc -vzu -w 5 HOST 3457

Block port 3457 in the firewall

ufw
sudo ufw deny 3457/tcp
iptables
sudo iptables -A INPUT -p tcp --dport 3457 -j DROP
nftables
sudo nft add rule inet filter input tcp dport 3457 drop
Windows Firewall
New-NetFirewallRule -DisplayName 'Block TCP 3457' -Direction Inbound -Protocol TCP -LocalPort 3457 -Action Block
ufw
sudo ufw deny 3457/udp
iptables
sudo iptables -A INPUT -p udp --dport 3457 -j DROP
nftables
sudo nft add rule inet filter input udp dport 3457 drop
Windows Firewall
New-NetFirewallRule -DisplayName 'Block UDP 3457' -Direction Inbound -Protocol UDP -LocalPort 3457 -Action Block

Related ports

3455prsvp3456vat3458d3winosfi3459integral

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