Design and implementation of voice mail in IP telephony based on Mediastreamer2

Mediastreamer2 is a module of processing sound and video streams, mainly used to encode, decode, process incoming and outgoing RTP packets. This paper modifies Mediastreamer2 properly based on its principle, making iLBC the preferred codec instead of the plug-in as before, then utilizes the interface functions to design the code framework and finally implements the voice mail in IP Telephony with the guarantee of quality and efficiency. It focuses on the modification of Mediastreamer2 and the design of voice mail, and then gives a test result in the end.