RFC 18:It is suggested that link 1 be used for the...
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1. It is suggested that link 1 be used for the HOST-HOST control link and link 0 be used for IMP-IMP control.

This will facilitate communication between Hosts and reduce delays
due to interference with IMP-IMP communications.

    [This RFC has been restored to on-line status by Elmar K. Bins]

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