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“K16304” — 2012/11/19 — 9:15
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5.2 Delay-Centric Strategy: Switch Transmission Path for Low Latency
127
Figure 5.4 CBR and SCTP MOS for G.711 at different data rates (Fitzpatrick et al.
2006).
MOS is similar to its offline calculation. The original heartbeat mechanism was mod-
ified to send multiple packets to imitate a VoIP traffic of a G.711 codec. A train of
25 heartbeat packets is sent to each endpoint in the association every T seconds. The
chunks were set to have size of 80 bytes transmitted every 10 ms. If packets were
excessively delayed they were considered lost. The loss rate was calculated consid-
ering a delay threshold of 300 to 350 ms ...