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RTP Stream Identification Algorithm

Step 0. The algorithm will query the UDP monitoring table. If the query is successful, it returns the
stream type flag in the monitoring table, and deletes the monitoring node from the monitoring table.
And then it goes to step5. If the query fails, the UDP payload length is first determined. If the length is
less than 12 bytes, no judgment is made. Otherwise, it goes to step1.

Step 1. The algorithm will check whether the upper two bits of the first byte of the UDP payload is
2 or not. If yes, it goes to step2. Otherwise, it goes to step6.

Step 2. The algorithm will record the value of PT, SSRC, timestamp, sequence number, and packet
direction into the stream table for comparison with subsequent packets. And then, it goes to step3.

Step 3. The algorithm will extract the PT, SSRC, timestamp, sequence number and direction of the
subsequent packet, and compare them with the saved values. If all the conditions in Formula (1-5) are
satisfied, it goes to step4. Otherwise, it goes to step6.

Step 4. The algorithm will compare the following n-1 packets according to the method of step3. If
there is a packet that does not satisfy the Formula (1-5), it goes to step6. If all the packets satisfy the
Formula (1-5), it goes to step5.