To pass data to a flash document, you can use "flashVars" property. But, I am wondering if what you want is even possible, as I am not knowledgeable on flash media server. Why not get the name from the user using asp.net and then pass it to the flash document using "flashVars" ?
Refer to this link for info about "flashVars"
http://helpx.adobe.com/flash/kb/pass-variables-swfs-flashvars.html[
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