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RFC 256 UNKNOWN INFRASTRUCTURE · MAINTENANCE

IMPSYS change notification

IMP system version 2513 lengthens host startup delay and adds interface testing.

On rfc-editor.org ↗
PUBLISHED
November 1971
AUTHORS
B. Cosell
STREAM
Legacy
NEW STARTUP DELAY
40 seconds to 1 minute 15 seconds
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   ]

ISO Plain Language

On this page
PROBLEMThe IMP system needed a longer startup interval before hosts could send and a way for the NCC to test faulty host interfaces.
MECHANISMVersion 2513 delays host messages for 40 seconds to 1 minute 15 seconds after startup and enables NCC-controlled tests of host interfaces.
SYSTEM CHANGESThe IMP could allow more startup time and help operators isolate host-interface communication faults.

§1Host Startup Delay

Version 2513 changes how long a host is prevented from sending messages into the network after it comes alive. The new interval is between 40 seconds and one minute 15 seconds, replacing the previous interval of between 30 seconds and one minute.

A host must wait longer after coming alive before sending messages. The new waiting period is between 40 seconds and one minute 15 seconds.

§2Host Interface Testing

The IMP gained the ability to test its host interfaces under control of the Network Control Center. BBN says the test can help isolate trouble when the communication path between an IMP and its host is faulty.

The Network Control Center can ask the IMP to test its connection to a host. The test is intended to help operators locate communication problems.

§3Version 2513

The notice says the new IMP system version would be installed shortly or might already have been installed when the notice was read. It identifies the startup delay and interface test as the two principal changes.

This notice describes two changes planned for IMP version 2513. It does not give additional implementation details.