Multibitrate live video publishing

I want to publish the video in multi-bitrate using flex web application to fms server(ex: same stream has to be publishing in 56,128,256 kbps to fms server), I can't use the FMLE for this purpose because I have to use customized video publishing component, is it possible to publish multi-bitrate stream without the help of FMLE? How can we achieve this?

I have googled but I am getting the answer for playing the multi-bitrate stream, Unable to get the answer as how to publish the multi-bitrate stream

Any help is appreciated.