1.5.  Intermediate News Servers

   For clusters of machines with many users (as might be the case in a
   university or large industrial environment), an intermediate server
   might be used.  This intermediate or "slave" server runs on each
   computer system, and is responsible for mediating news reading
   requests and performing local caching of recently-retrieved news
   articles.

   Typically, a client attempting to obtain news service would first
   attempt to connect to the news service port on the local machine.  If
   this attempt were unsuccessful, indicating a failed server, an
   installation might choose to either deny news access, or to permit
   connection to the central "master" news server.

   For workstations or other small systems, direct connection to the
   master server would probably be the normal manner of operation.

   This specification does not cover the operation of slave NNTP
   servers.  We merely suggest that slave servers are a logical addition
   to NNTP server usage which would enhance operation on large local
   area networks.