network
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the HOST network program must generate a dummy message
merely to keep the link open?
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... 3. A HOST has to be prepared to repeat transmissions of a message
into network (see, e.g., Page 17, BBN 1822) therefore why the
special discardable NOP message (Page 12, BBN 1822).
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... Normally the times involved differ by many orders of magnitude but a
high priority non-network HOST responsibility could delay next bit for
a long time.
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