RFC 15:Network Subsystem for Time Sharing Hosts
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1. Introduction

   A set of network primitives has been defined (Network Working Group
   Note 11) for inclusion in the monitor systems of the respective
   HOSTS.  These primitives are at the level of system calls: SPOP's or
   BRS's on the 940; UUO's on the PDP-10.  Presumably these UUO's are
   accessible to all user programs when executing for users whose status
   bits allow network access.

   In addition to user program access, a convenient means for direct
   network access from the terminal is desirable.  A sub-system called
   "Telnet" is proposed which is a shell program around the network
   system primitives, allowing a teletype or similar terminal at a
   remote host to function as a teletype at the serving host.

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