Port 11600 (tempest-port)

IANA assigns port 11600 to tempest-port: Tempest Protocol Port.

Registered (user) port, 1024-49151 TCPUDP

IANA assignment

Service nameProtoDescriptionAssigneeReference

tempest-port TCP Tempest Protocol Port Francis Cianfrocca -

tempest-port UDP Tempest Protocol Port Francis Cianfrocca -

Linux: is anything listening on TCP 11600?

sudo ss -tlnp 'sport = :11600'

Linux: UDP 11600

sudo ss -ulnp 'sport = :11600'

Linux / macOS: which process owns the port

sudo lsof -nP -i :11600

Older Linux / BSD (net-tools)

sudo netstat -tlnp | grep ':11600 '

Windows (Command Prompt)

netstat -ano | findstr :11600

Windows (PowerShell)

Get-NetTCPConnection -LocalPort 11600 -State Listen | Select LocalAddress,OwningProcess

From another machine

nc -vz -w 5 HOST 11600

From Windows

Test-NetConnection HOST -Port 11600

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

nc -vzu -w 5 HOST 11600

ufw

sudo ufw deny 11600/tcp

iptables

sudo iptables -A INPUT -p tcp --dport 11600 -j DROP

nftables

sudo nft add rule inet filter input tcp dport 11600 drop

Windows Firewall

New-NetFirewallRule -DisplayName 'Block TCP 11600' -Direction Inbound -Protocol TCP -LocalPort 11600 -Action Block

ufw

sudo ufw deny 11600/udp

iptables

sudo iptables -A INPUT -p udp --dport 11600 -j DROP

nftables

sudo nft add rule inet filter input udp dport 11600 drop

Windows Firewall

New-NetFirewallRule -DisplayName 'Block UDP 11600' -Direction Inbound -Protocol UDP -LocalPort 11600 -Action Block

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