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Port 4787 (sia-ctrl-plane)

IANA assigns port 4787 to sia-ctrl-plane: Service Insertion Architecture (SIA) Control-Plane.

Registered (user) port, 1024-49151 TCP

IANA assignment

Service nameProtoDescriptionAssigneeReference
sia-ctrl-plane TCP Service Insertion Architecture (SIA) Control-Plane Shree Murthy -

Registry dates for this port: registered 2009-10-29.

Check what is listening on port 4787

Linux: is anything listening on TCP 4787?
sudo ss -tlnp 'sport = :4787'
Linux / macOS: which process owns the port
sudo lsof -nP -i :4787
Older Linux / BSD (net-tools)
sudo netstat -tlnp | grep ':4787 '
Windows (Command Prompt)
netstat -ano | findstr :4787
Windows (PowerShell)
Get-NetTCPConnection -LocalPort 4787 -State Listen | Select LocalAddress,OwningProcess

Test it from outside

From another machine
nc -vz -w 5 HOST 4787
From Windows
Test-NetConnection HOST -Port 4787

Block port 4787 in the firewall

ufw
sudo ufw deny 4787/tcp
iptables
sudo iptables -A INPUT -p tcp --dport 4787 -j DROP
nftables
sudo nft add rule inet filter input tcp dport 4787 drop
Windows Firewall
New-NetFirewallRule -DisplayName 'Block TCP 4787' -Direction Inbound -Protocol TCP -LocalPort 4787 -Action Block

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4785cncp4786smart-install4788xmcp4789VXLAN

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Assignment data: IANA port number registry (public domain), retrieved 2026-11-10.