Port 21845
webphone · TCP/UDP
| Range | Registered port (1024–49151) |
|---|---|
| Protocol | TCP/UDP |
| Service | webphone |
Frequently asked questions
What is port 21845 used for?
Port 21845 is registered with the IANA for webphone (TCP/UDP). Description: webphone.
Is port 21845 a well-known port?
No. Port 21845 is in the range 1024–49151 (registered or user ports). Ordinary programs may open it without root privileges.
How do I check whether port 21845 is open?
Locally on Linux with ss -tulpn | grep ':21845\b', on Windows with netstat -ano | findstr :21845. To test a remote host use Test-NetConnection <host> -Port 21845 in PowerShell or nc -zv <host> 21845 on Linux/macOS.
How do I open port 21845 in the firewall?
Ubuntu/Debian (ufw): sudo ufw allow 21845/tcp. Fedora/RHEL (firewalld): sudo firewall-cmd --add-port=21845/tcp --permanent, then firewall-cmd --reload. Windows (PowerShell as administrator): New-NetFirewallRule -DisplayName "Port 21845" -Direction Inbound -Protocol TCP -LocalPort 21845 -Action Allow.
IANA registry entries
| Protocol | Service | Description (IANA) |
|---|---|---|
| TCP | webphone | webphone |
| UDP | webphone | webphone |