From 4bfd864f10b68b71482b35c818559068ef8d5797 Mon Sep 17 00:00:00 2001 From: Thomas Voss Date: Wed, 27 Nov 2024 20:54:24 +0100 Subject: doc: Add RFC documents --- doc/rfc/rfc565.txt | 283 +++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 283 insertions(+) create mode 100644 doc/rfc/rfc565.txt (limited to 'doc/rfc/rfc565.txt') diff --git a/doc/rfc/rfc565.txt b/doc/rfc/rfc565.txt new file mode 100644 index 0000000..f35da2c --- /dev/null +++ b/doc/rfc/rfc565.txt @@ -0,0 +1,283 @@ + + + + + + +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 [Page 1] + +RFC 565 Storing Network Survey Data 28 August 1973 + + + logger available and responding within 20 seconds + + SURVEY records response times responding in tenths of seconds. + + When the data for all 28 hosts has been assembled, SURVEY transmits + that data to CCA's datacomputer. If for some reason the datacomputer + cannot accept the information, it is held at DMS and sent another + time. + + The datacomputer's survey database is inverted by host, status, + month, and year. That is to say that the datacomputer maintains + several indices to records of one attempt to establish a full duplex + connection to one host's logger: it maintains one such index for each + host, one for each status, one for each month, and one for each year. + The datacomputer can select records that are specified in boolean + expressions by performing boolean operations on the inversion, and + without consulting the data itself. The inversion thus facilitates + rapid interaction between the survey retrieval program described + below and the survey database at the datacomputer. + + SURVEY expresses the record of each attempt to access one host in 17 + ASCII characters. The record of one survey then occupies 17 * 28 = + 476 characters, and each day the datacomputer receives 3 * 24 * 476 = + 34,272 characters from DMS. + +Part 2: Retrieving Survey Data + + A Program called SURRET, written at DMS in the language MUDDLE, + allows one to selectively retrieve material from the survey data base + stored at the datacomputer [3]. Its user may specify values, groups + of values, or, where appropriate, upper and lower bounds for values + of each of five fields: host name, date, time, response time, and + host status. In addition, one may request that all five fields or + any subset of the five be retrieved. A sample interaction with + SURRET is reproduced below. + + $ + "OK" + $ + "OK" +