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+# dlnaprox
+
+This program is a DLNA proxy. It proxies UDP multicast packets to and from the
+specified networks. These two networks are knowns as the inner and the outer
+network. The basic assumption is that the inner network can send normal IP
+requests to the outer network, but not visa versa. For example, a Docker
+container on a bridged docker network can only be accessed through forwarded
+ports. However, if it sends a request to an address on the same network as the
+host system, by default, the other host is reachable. This program forwards
+multicast broadcasts to 239.255.255.250:1900 to the other network. Since the
+spec says that responses to the broadcast should sent to port that originated
+it. So we keep a map of sockets so we can correctly proxy these responses.
+
+## Usage
+
+```bash
+dlnaprox -i 172.17.0.0/16 -o 192.168.0.0/24
+```
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