HTTPfy

Port 3320 (officelink2000)

IANA assigns port 3320 to officelink2000: Office Link 2000.

Registered (user) port, 1024-49151 TCPUDP

IANA assignment

Service nameProtoDescriptionAssigneeReference
officelink2000 TCP Office Link 2000 Mike Balch -
officelink2000 UDP Office Link 2000 Mike Balch -

Check what is listening on port 3320

Linux: is anything listening on TCP 3320?
sudo ss -tlnp 'sport = :3320'
Linux: UDP 3320
sudo ss -ulnp 'sport = :3320'
Linux / macOS: which process owns the port
sudo lsof -nP -i :3320
Older Linux / BSD (net-tools)
sudo netstat -tlnp | grep ':3320 '
Windows (Command Prompt)
netstat -ano | findstr :3320
Windows (PowerShell)
Get-NetTCPConnection -LocalPort 3320 -State Listen | Select LocalAddress,OwningProcess

Test it from outside

From another machine
nc -vz -w 5 HOST 3320
From Windows
Test-NetConnection HOST -Port 3320
UDP probe (no reply does not prove it is closed)
nc -vzu -w 5 HOST 3320

Block port 3320 in the firewall

ufw
sudo ufw deny 3320/tcp
iptables
sudo iptables -A INPUT -p tcp --dport 3320 -j DROP
nftables
sudo nft add rule inet filter input tcp dport 3320 drop
Windows Firewall
New-NetFirewallRule -DisplayName 'Block TCP 3320' -Direction Inbound -Protocol TCP -LocalPort 3320 -Action Block
ufw
sudo ufw deny 3320/udp
iptables
sudo iptables -A INPUT -p udp --dport 3320 -j DROP
nftables
sudo nft add rule inet filter input udp dport 3320 drop
Windows Firewall
New-NetFirewallRule -DisplayName 'Block UDP 3320' -Direction Inbound -Protocol UDP -LocalPort 3320 -Action Block

Related ports

3318ssrip3319sdt-lmd3321vnsstr3326sftu

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