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| • |
Voice needs RTT
< 250ms or else listener does not know
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when to speak
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RTT > 400ms
makes productive interactive work such as
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interactive
telnet/X-windows style typing difficult
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Screen does not
match the keyboard, especially when correcting text
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Losses:
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Losses > 10%
TCP connections fail
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Losses >4-6%
make video conferencing unintelligible for non-native
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language speakers
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Losses of >
3-5% make TCP perform badly
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Random loss of
2.5% will make Voice over IP annoying every 30
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seconds or so
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More realistic
burst losses will cause VoIP to be annoying at >1%
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losses
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