You could setup HTTP on port 80 and RTMPT on port 80 as well.
We need to modify is the server properties file located in the conf directory: red5_path/conf/red5.properties
- Locate the http.port key and change it to 80 instead of 5080
- Do not change the rtmpt.port entry, it should be 8088
- Save and close the file
Reference: gregoire.org