- Close the port if nothing on the host needs it.
- Identify the process that listens on it (commands below) before opening it in a firewall.
- Expose a service only to the networks that use it.
Port 5550: Model Railway control using the CBUS message protocol
Port 5550 is assigned by IANA to cbus (Model Railway control using the CBUS message protocol).
How cbus works
Other servicesThe client sends a request to port 5550 and the cbus service answers.
- Transport
- TCP
- Exposure risk
- not rated depends on the program listening
- Encryption
- Unknownnot stated by the registry
- IANA status
- Assigned1 registered service
- Range
- Registered (1024-49151)
- Category
- Other services
Is port 5550 dangerous?
We have no specific security note for port 5550. Its risk depends on the program actually listening on it. General advice for other services services:
IANA registry entries for port 5550
| Service | Port | Transport | Description | Reference | Updated |
|---|---|---|---|---|---|
| cbus | 5550 | TCP | Model Railway control using the CBUS message protocol | - | 2017-01-03 |
| - | 5550 | - | Reserved | - | - |
// source: IANA service name and port number registry
Which program uses port 5550, and is it reachable?
Linux
sudo ss -ltnup 'sport = :5550' # process listening on 5550
sudo lsof -nP -i :5550macOS
sudo lsof -nP -i :5550
Windows (PowerShell)
Get-NetTCPConnection -LocalPort 5550 -State Listen | Select LocalAddress, OwningProcess Get-NetUDPEndpoint -LocalPort 5550 netstat -ano | findstr :5550
From another machine
nmap -p 5550 -sV <host> nc -zv <host> 5550
Block it in the firewall
sudo ufw deny 5550/tcp # Linux (ufw) New-NetFirewallRule -DisplayName "Block 5550" -Direction Inbound -LocalPort 5550 -Protocol TCP -Action Block # Windows
What is port 5550 used for?
Port 5550 is assigned by IANA to cbus (Model Railway control using the CBUS message protocol).
Is port 5550 TCP or UDP?
Port 5550 is registered for TCP.
Is it safe to open port 5550?
It depends on the program that listens on it. Open it only for a service you know and only to the networks that need it. Close the port if nothing on the host needs it.
How do I check if port 5550 is open?
On Linux run "ss -ltnup 'sport = :5550'", on macOS "lsof -nP -i :5550", and on Windows "netstat -ano | findstr :5550" to see the local process. From another machine, "nmap -p 5550 <host>" shows whether it is reachable.