RFC 565 (rfc565) - Page 1 of 5


Storing network survey data at the datacomputer



Alternative Format: Original Text Document



Network Working Group                                          D. Cantor
Request for Comments: 565                Computer Corporation of America
NIC: 18777                                                28 August 1973


            Storing Network Survey Data at the Datacomputer

   In November, 1972, Computer Corporation of America (CCA) and the
   Programming Technology Division of the Dynamics Modeling System (DMS)
   at M.I.T.'s Project MAC began planning to transmit to CCA's
   datacomputer [1] information about the behavior of ARPA network hosts
   collected by DMS's program SURVEY [2].  The information was to be
   stored at the datacomputer and retrieved by an interactive program
   that would address the datacomputer from DMS's PDP-10.

   One goal of this joint project was to enable DMS to retain all of the
   information that SURVEY collects: SURVEY had been running since late
   1971, saving only a short daily summary of its findings and
   discarding potentially useful details.  A second goal was to discover
   and remove shortcomings in the interface between CCA's datacomputer
   and a program running at a remote host.

   The project was completed last month, and the programs described in
   this document have been operating successfully with the datacomputer
   since July 10.

   Part 1, below, describes SURVEY's output.  Part 2 describes a program
   that retrieves portions of that output from the datacomputer.

Part 1: The Survey Database

   Every twenty minutes, DMS's program SURVEY wakes up and performs the
   initial connection protocol from the PDP-10 at DMS to the logger
   socket (socket 1) of each 28 network hosts.

   SURVEY records a date time, host, status,and response time for each
   host.  A host may be in one of these states:

      undetermined or not surveyed

      disconnect from the network or dead

      network control program not responding

      ICP to logger aborted by the host

      ICP to logger timed out by SURVEY after 20 seconds




Cantor