3.2.1 Abstract Data Model

Common to both the sending rates are the following variables (per session).

RTCPSendingRate: Defines the rate at which RTCP reports are sent. Reports are sent either at a packet pair fast rate, at the normal rate, or at the packet train fast rate. The packet pair fast rate uses a fixed time interval, which is defined by the fast RTCP packet pair sending timer. The normal rate uses a random time interval based on a value that scales with the number of SSRCs in the conference, as defined in [RFC3550] Section 6.2. The packet train fast rate also uses a fixed time interval, which is defined by the fast RTCP packet train sending timer.

FastRTCPPacketPairCount: Keeps track of how many packet pairs have been sent at the fast RTCP send rate.

ReceivingRTCPPacketPairs: Indicates whether or not RTCP packet pairs have been received.

BandwidthEstSendingMode: Indicates whether RTCP packet pair or packet train is sent to estimate bandwidth.

FastRTCPPacketTrainCount: Keeps track of how many packet trains have been sent at the fast RTCP packet train send rate.