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Port 1550 (3m-image-lm)

IANA assigns port 1550 to 3m-image-lm: Image Storage license manager 3M Company.

Registered (user) port, 1024-49151 TCPUDP

IANA assignment

Service nameProtoDescriptionAssigneeReference
3m-image-lm TCP Image Storage license manager 3M Company J C Canessa -
3m-image-lm UDP Image Storage license manager 3M Company J C Canessa -

Check what is listening on port 1550

Linux: is anything listening on TCP 1550?
sudo ss -tlnp 'sport = :1550'
Linux: UDP 1550
sudo ss -ulnp 'sport = :1550'
Linux / macOS: which process owns the port
sudo lsof -nP -i :1550
Older Linux / BSD (net-tools)
sudo netstat -tlnp | grep ':1550 '
Windows (Command Prompt)
netstat -ano | findstr :1550
Windows (PowerShell)
Get-NetTCPConnection -LocalPort 1550 -State Listen | Select LocalAddress,OwningProcess

Test it from outside

From another machine
nc -vz -w 5 HOST 1550
From Windows
Test-NetConnection HOST -Port 1550
UDP probe (no reply does not prove it is closed)
nc -vzu -w 5 HOST 1550

Block port 1550 in the firewall

ufw
sudo ufw deny 1550/tcp
iptables
sudo iptables -A INPUT -p tcp --dport 1550 -j DROP
nftables
sudo nft add rule inet filter input tcp dport 1550 drop
Windows Firewall
New-NetFirewallRule -DisplayName 'Block TCP 1550' -Direction Inbound -Protocol TCP -LocalPort 1550 -Action Block
ufw
sudo ufw deny 1550/udp
iptables
sudo iptables -A INPUT -p udp --dport 1550 -j DROP
nftables
sudo nft add rule inet filter input udp dport 1550 drop
Windows Firewall
New-NetFirewallRule -DisplayName 'Block UDP 1550' -Direction Inbound -Protocol UDP -LocalPort 1550 -Action Block

Related ports

1548axon-lm1549shivahose, shivasound1551hecmtl-db1552pciarray

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