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S7200 TV Signal Analyzer Operation Manual
RTP usually runs on UDP, and uses its multiplexing and checksum features. Note
that RTP does not provide any control of the quality of service or reservation of
network resources.
Real-Time Control Protocol (RTCP)
RTCP is used in conjunction with RTP. It gives feedback to each participant in an
RTP session that can be used to control the session. The messages include
reception reports, including number of packets lost and jitter statistics (early or
late arrivals). This information potentially can be used by higher layer applications
to modify the transmission. For example, the bit rate of a stream could be changed
to counter network congestion. Some RTCP messages relate to control of a video
conference with multiple participants.
Media Delivery Index
Both packet delay and packet loss have been taken into account by IETF RFC 4445.
This RFC describes Media Delivery Index (MDI) and it is defined as a single figure
of merit used to quantify 2 IP transport impairments, namely Packet Jitter or Delay
and Packet Loss. These two test parameters are defined as Media Delay Factor
(MDI-DF) and Media Loss Rate (MDI-MLR).
The Delay Factor indicates how long a data stream must be buffered (i.e. delayed)
at its nominal bit rate to prevent packet loss.
The Media Loss Rate is the number of packets lost during a period of 1 second.
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