B. CCN Hardware

CCN operates an IBM 360/91KK, i.e., a Model 91 CPU with a 4 million byte fast memory.

      CPU Speed:      Highly program-dependent; 2-6 Mips, with 3 Mips as a
                      useful average.  The upper end of this range occurs
                      heavy floating point in the inner loops.  The decimal
                      arithmetic operation of a 360 should be avoided as
                      they are executed interpretively by the 91.

      Memory Speed:   Memory is interleaved 16 ways and extensively
                      buffered. Effective memory fetch time is 600 ns in
                      lower 2 million bytes, 900 ns in upper 2 million
                      bytes.

      I/O Con-
      figuration      a) 6 2860       Selector Channels
                      b) 1 2870       Multiplexor Channcl (with 16 control
                                      unit RPQ)
                      c) 5 2314       Disk Storage Units (i.e., 40 disk
                                      drives).
                      d) 1 2301       Drum (Systems residence and catalog
                                      only.)
                      e) 5 (245x)     9 track tape drives (80O bpi)
                      f) 3 (240x)     7 tracts tape drives (200/556/800 bpi)
                      g) 1  2291      (Modified 2250 CRT) Operator/
                                      Maintenance Console.

                      Also on the Multiplexor Channel are:

                      h) 2 card readers and 4 high speed printers at CCN;

                      i) Four 40,000 baud interfaces for CCI alphanumeric
                         TV display consoles (currently supporting 40
                         consoles);

                      j) Six data communication ports (3 dial @ 2000 baud,
                         1 dedicated @ 4800 baud, and 2 dedicated @ 50,000
                         baud) for remote batch entry terminals;

                      k) a Calcomp plotter;

                      l) an interface for BBS Teleputers (the Culler-Fried
                         system);

                      m) Ten dial ports for 2741 typewriter terminals;
                         and finally:

                      n) the IMP Interface