Port 1638
ismc · TCP/UDP
| Range | Registered port (1024–49151) |
|---|---|
| Protocol | TCP/UDP |
| Service | ismc |
Frequently asked questions
What is port 1638 used for?
Port 1638 is registered with the IANA for ismc (TCP/UDP). Description: ISP shared management control.
Is port 1638 a well-known port?
No. Port 1638 is in the range 1024–49151 (registered or user ports). Ordinary programs may open it without root privileges.
How do I check whether port 1638 is open?
Locally on Linux with ss -tulpn | grep ':1638\b', on Windows with netstat -ano | findstr :1638. To test a remote host use Test-NetConnection <host> -Port 1638 in PowerShell or nc -zv <host> 1638 on Linux/macOS.
How do I open port 1638 in the firewall?
Ubuntu/Debian (ufw): sudo ufw allow 1638/tcp. Fedora/RHEL (firewalld): sudo firewall-cmd --add-port=1638/tcp --permanent, then firewall-cmd --reload. Windows (PowerShell as administrator): New-NetFirewallRule -DisplayName "Port 1638" -Direction Inbound -Protocol TCP -LocalPort 1638 -Action Allow.
IANA registry entries
| Protocol | Service | Description (IANA) |
|---|---|---|
| TCP | ismc | ISP shared management control |
| UDP | ismc | ISP shared management control |