All ports
Port1638/UDP
ismcPort
1638
Protocol
UDP
Category
Registered
Service
ismc
What is port 1638?
Port 1638/UDP is a Registered port, registered with IANA for specific applications. It is associated with the ismc service.
ISP shared management control
Useful commands
nmapnmap -p 1638 -sV example.comnetcatnc -zv example.com 1638curlcurl -v http://example.com:1638/telnettelnet example.com 1638bash(echo > /dev/udp/example.com/1638) 2>/dev/nullFirewall commands
UFWAllow
sudo ufw allow 1638/udpDeny
sudo ufw deny 1638/udpiptablesAllow
sudo iptables -A INPUT -p udp --dport 1638 -j ACCEPTDeny
sudo iptables -D INPUT -p udp --dport 1638 -j ACCEPTfirewalldAllow
sudo firewall-cmd --permanent --add-port=1638/udpWindowsAllow
netsh advfirewall firewall add rule name="Open Port 1638" dir=in action=allow protocol=UDP localport=1638Security Risks
- Unauthorized access to the service
- Data exposure if the service is unauthenticated
- Outdated versions with vulnerabilities
- Incorrect service configuration
Frequently Asked Questions
What service runs on port 1638/UDP?
Port 1638/UDP is associated with the ismc service. ISP shared management control
Is it safe to expose port 1638 to the Internet?
It depends on the service and configuration. Port 1638 (ismc) is a Registered port. If you need to expose it, keep the service updated, use strong authentication, and configure a firewall. It's always recommended to restrict access by IP when possible.
How do I check if port 1638 is open?
You can use nmap: `nmap -p 1638 -sV example.com`, netcat: `nc -zv example.com 1638`, or the bash command: `(echo > /dev/udp/example.com/1638) 2>/dev/null && echo "Open" || echo "Closed"`.
How do I open or close port 1638 on my firewall?
On Linux with UFW: `sudo ufw allow 1638/udp` (open) or `sudo ufw deny 1638/udp` (close). With iptables: `sudo iptables -A INPUT -p udp --dport 1638 -j ACCEPT`. On Windows: `netsh advfirewall firewall add rule name="Open Port 1638" dir=in action=allow protocol=UDP localport=1638`.
What applications and services use port 1638?
Port 1638/UDP is used by the ismc service. Specific uses depend on the software and configuration. Check our related tools section for more information.