Keith Winstein
34 lines
988 B
Plaintext
34 lines
988 B
Plaintext
1. server maintains:
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every frame it has ever been in.
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every packet it has ever sent.
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packet has: frame no, frame it depends on (maybe nothing),
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0 server's Last Known Client Frame
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client has told us the latest frame it can now contruct
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some packets have transmitted frames > this recently, but those
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frames haven't yet been acked
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some packets may have transmitted frames > this long ago
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and haven't been acked. we call those lost
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2. most recent frame is "current frame"
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most recent frame not lost is "presumed client frame"
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most recent frame acked is "last known client frame"
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3. goal: transmit current frame to client by most efficient means
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could send packet depending on "nothing", "presumed client frame",
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or "last known client frame"
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4. when client gets a packet, it tells us the latest frame it
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can now construct
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5. when sending packet, server tells client last known client frame.
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client discards all frames older than this.
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