In addition to the traffic generation SIPp also measures and stores the information about the length of the SIP message exchanges, therefore it is used to measure defined parameters RRD and SRD. Except of that, the information about the total number of created calls and the number of successful ones is also measured by SIPp. These data are stored on every UAC computer in the text format and the main UAC downloads and renames this files at the end of each step (loop) in the test scenario. To get the information, about the RTP stream Tshark is used in our implementation. During the each test step (loop) of the B2BUA testing scenario one call is generated on one dedicated computer and forwarded to the B2BUA. It then handles the call as any other. The media stream is then echoed back by the UAS and after the passing the B2BUA again it is forwarded back to its source. So, on this dedicated computer the network capture is run and it stores the originating media low and the one hat is echoed back. From the differences between these two captured media streams many information can be obtained such as round trip time, packet loss, packet delay or jitter. For our purposes only last two named parameters are evaluated, because they bear the main information.
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