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RFC 256 UNKNOWN INFRASTRUCTURE · MAINTENANCE

IMPSYS change notification

Software changes to the ARPA Network IMP system

On rfc-editor.org ↗
PUBLISHED
November 1971
AUTHORS
B. Cosell
STREAM
Legacy
IMP SYSTEM VERSION
2513
NEW STARTUP DELAY
40 seconds to 1 minute 15 seconds
PREVIOUS DELAY
30 seconds to 1 minute
DOI
10.17487/RFC0256

RFC text

Original text · RFC Editor View on rfc-editor.org ↗ 
Network Working Group                                B. Cosell
RFC #256                                             BBN
NIC #7697                                            3 November 1971
Categories:  B.1
Updates:  None
Obsoletes:  None


                       IMPSYS Change Notification

        We will shortly install (or perhaps will have already
   installed) a new version of the IMP system, Version 2513.  The
   new version incorporates two principal changes:

     1.  A Host will be prevented from sending any messages
         into the Network for between 40 seconds and a
         minute and a quarter after he comes alive (this
         has been changed from between 30 seconds and a
         minute).

     2.  The IMP has been given the ability to test its Host
         interfaces under control of the NCC.  This will help
         us isolate the trouble when the IMP Host communication
         path is faulty.


     BC/jm


       [ This RFC was put into machine readable form for entry ]
       [ into the online RFC archives by BBN Corp. under the   ]
       [ direction of Alex McKenzie.                   12/96   ]

AI ELI5

On this page
PROBLEMThe IMP system needs adjustments to host startup behavior and troubleshooting capabilities.
MECHANISMIMP system version 2513 increases the startup delay before a host can send messages into the network from 30-60 seconds to 40 seconds to 1 minute 15 seconds, and adds the ability for the Network Control Center to test IMP host interfaces.
SYSTEM IMPROVEMENTSBetter reliability during host startup and improved ability to diagnose host-to-IMP connection problems.

§1Introduction

RFC 256 announces a new version of the IMP system, version 2513, which was to be installed shortly on the ARPA Network. The version incorporates two principal changes affecting host startup and network troubleshooting.

The network is getting a software update with two improvements.

§2Increased Host Startup Delay

A host will now be prevented from sending any messages into the network for between 40 seconds and 1 minute 15 seconds after it comes alive. This is an increase from the previous limit of 30 seconds to 1 minute. The longer delay allows the host and IMP to stabilize their connection before network traffic begins.

When a computer turns on and connects to the network box, it must wait longer before it can send its first messages.

§3IMP Host Interface Testing

The IMP has been given the ability to test its host interface under control of the Network Control Center (NCC). This testing capability helps operators isolate problems when the communication path between the IMP and its host is faulty, reducing the time and effort needed to diagnose and repair connection issues.

The network box can now check if its cable to the computer is working properly, which helps find broken connections faster.