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Port 3433 (opnet-smp)

IANA assigns port 3433 to opnet-smp: OPNET Service Management Platform.

Registered (user) port, 1024-49151 TCPUDP

IANA assignment

Service nameProtoDescriptionAssigneeReference
opnet-smp TCP OPNET Service Management Platform OPNET Technologies Inc -
opnet-smp UDP OPNET Service Management Platform OPNET Technologies Inc -

Registry dates for this port: registered 2002-03, last modified 2011-09-21.

Check what is listening on port 3433

Linux: is anything listening on TCP 3433?
sudo ss -tlnp 'sport = :3433'
Linux: UDP 3433
sudo ss -ulnp 'sport = :3433'
Linux / macOS: which process owns the port
sudo lsof -nP -i :3433
Older Linux / BSD (net-tools)
sudo netstat -tlnp | grep ':3433 '
Windows (Command Prompt)
netstat -ano | findstr :3433
Windows (PowerShell)
Get-NetTCPConnection -LocalPort 3433 -State Listen | Select LocalAddress,OwningProcess

Test it from outside

From another machine
nc -vz -w 5 HOST 3433
From Windows
Test-NetConnection HOST -Port 3433
UDP probe (no reply does not prove it is closed)
nc -vzu -w 5 HOST 3433

Block port 3433 in the firewall

ufw
sudo ufw deny 3433/tcp
iptables
sudo iptables -A INPUT -p tcp --dport 3433 -j DROP
nftables
sudo nft add rule inet filter input tcp dport 3433 drop
Windows Firewall
New-NetFirewallRule -DisplayName 'Block TCP 3433' -Direction Inbound -Protocol TCP -LocalPort 3433 -Action Block
ufw
sudo ufw deny 3433/udp
iptables
sudo iptables -A INPUT -p udp --dport 3433 -j DROP
nftables
sudo nft add rule inet filter input udp dport 3433 drop
Windows Firewall
New-NetFirewallRule -DisplayName 'Block UDP 3433' -Direction Inbound -Protocol UDP -LocalPort 3433 -Action Block

Related ports

3431ndl-als3432osdcp3434opencm3435pacom

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