502 Bad Gateway appears when my website url contains 8081 port

My website contains an iframe having an url with port mentioned. The URL works from my system but 开发者_Python百科when i tried from an institute LAN that iframe didnt appear, and that request showed 502 Bad Gateway on Javascript Console. Can there be a workaround to make it work in the institute.

Also the server for 8081 is created using this php script:

$server = $daemon->create('httpdServer','httpdServerClient',0,8081);