RTCPHeader

This field identifies the version of RTP

If the padding bit is set, this individual RTCP packet contains some additional padding octets at the end which are not part of the control information but are included in the length field. The last octet of the padding is a count of how many padding octets should be ignored, including itself (it will be a multiple of four). Padding may be needed by some encryption algorithms with fixed block sizes. In a compound RTCP packet, padding is only required on one individual packet because the compound packet is encrypted as a whole for the method in Section 9.1. Thus, padding must only be added to the last individual packet, and if padding is added to that packet, the padding bit must be set only on that packet. This convention aids the header validity checks described in Appendix A.2 and allows detection of packets from some early implementations that incorrectly set the padding bit on the first individual packet and add padding to the last individual packet.

Undocumented

The synchronization source identifier for the originator of this packet.