Cross-platform NAT behavior discovery (algorithms defined in RFC3489 and RFC5780)

When it is useful?

Features

• Ready to use on your platform, no requirements, no installing, no administrative privileges

• Discovers following types (RFC3489):

  • Full Cone
  • Restricted Cone
  • Port Restricted Cone
  • Symmetric
  • No NAT (Open Internet, Blocked, Symmetric UDP Firewall)

• Determining NAT Mapping Behavior (RFC5780):

  • Endpoint Independent Mapping
  • Address Dependent Mapping
  • Address and Port Dependent Mapping
  • No NAT (Open Internet, Blocked, Symmetric UDP

• Determining NAT Filtering Behavior (RFC5780):

  • Endpoint-Independent Filtering
  • Address-Dependent Filtering
  • Address and Port-Dependent Filtering
  • No NAT (Open Internet, Blocked, Symmetric UDP

Configuration

> nat-discovery --help

usage: nat-discovery [-h] [-d] [-j] [-e] [-H STUN_HOST] [-P STUN_PORT] [-i SOURCE_IP] [-p SOURCE_PORT] [--version]

optional arguments:
  -h, --help            show this help message and exit
  -d, --debug           enable debug logging (default: False)
  -H STUN_HOST, --stun-host STUN_HOST
                        STUN host to use (default: None)
  -P STUN_PORT, --stun-port STUN_PORT
                        STUN host port to use (default: 3478)
  -i SOURCE_IP, --source-ip SOURCE_IP
                        network interface for client (default: 0.0.0.0)
  -p SOURCE_PORT, --source-port SOURCE_PORT
                        port to listen on for client (default: 54320)
  --version             show program's version number and exit