How to use the command 'stun' (with examples)
The ‘stun’ command is a classic STUN (Session Traversal Utilities for NAT) client. STUN is a protocol used to discover the public IP address and port number of an NATed (Network Address Translated) device. It is commonly used in VoIP (Voice over IP) and WebRTC (Web Real-Time Communication) applications to establish peer-to-peer connections. The ‘stun’ command allows users to make STUN requests and obtain information about their network setup.
Use case 1: Make a STUN request
Code:
stun stun.1und1.de
Motivation:
- This use case is useful when you want to check your NAT type and obtain your public IP address and port number using a STUN server.
- By making a STUN request, you can determine if you are behind a symmetric NAT, a full cone NAT, a restricted cone NAT, or a port-restricted cone NAT. This information can be helpful in diagnosing network connection issues.
Explanation:
stun stun.1und1.de: This command specifies the STUN server to send the request to. In this case, we are using the STUN server hosted at stun.1und1.de.
Example output:
address: 55.555.55.555
port: 12345
The output shows the public IP address (55.555.55.555) and port number (12345) obtained from the STUN server.
Use case 2: Make a STUN request and specify the source port
Code:
stun stun.1und1.de -p 4302
Motivation:
- This use case is useful when you need to specify a specific source port for the STUN request.
- Some applications or network configurations may require specific source port numbers to be used for STUN requests. By specifying the source port, you can ensure that the STUN request complies with these requirements.
Explanation:
stun stun.1und1.de: This command specifies the STUN server to send the request to. In this case, we are using the STUN server hosted at stun.1und1.de.-p 4302: This argument specifies the source port for the STUN request. In this example, we are using port 4302 as the source port.
Example output:
address: 55.555.55.555
port: 12345
The output shows the public IP address (55.555.55.555) and port number (12345) obtained from the STUN server. The specified source port (4302) is used for the request.
