Streaming - pause transferring a file on server side

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http://stackoverflow.com – I am trying to make an Android application which uses the speaker of another device (in addition to server's speakers) to play audio files using Bluetooth. However as of now, I haven't figured out exactly how I'll synchronize playing. The activity will contain a button which will allow the user to toggle between play and pause. But I want the server to stop transfer of the file if the user wants to pause the media. This obviously requires some code on the server side. But I am unable to figure out how I'll do that. Can anybody guide me how can I implement this logic ?? Thanks (HowTos)