IMP System Change Notification

We are planning to release IMPSYS 2600 on May 15, 1972, be- tween

12 noon and 3 p.m. E.D.T. As discussed at the March 16 seminar held

at BBN, this release constitutes a major change to the IMP program.

Because of the magnitude of the change, the system will be released on

an experimental basis. If problems develop, then the current system,

IMPSYS 2514, will be reloaded and the cutover for IMPSYS 2600 will be

rescheduled for some later time.

The actual transfer over to IMPSYS 2600 will require assis- tance

from site personnel, and we hereby request this assistance. A new

tape of IMPLOD 2600 will be mailed to all sites shortly, and the staff

at BBN will request each site in turn on May 15 to load the new IMPLOD

tape and will detail other procedures to follow thereafter. We prefer

that each site have someone who is familiar with IMP system operation

on hand at this time. At some sites, we may request additional

assistance from the computer operations staffs or programmers in the

case of any problems. We also advise site personnel to refrain from

scheduling produc- tion over the Network during the hours of

switchover, since unforeseen difficulties may arise.

It is anticipated that the Hosts will not see any first- order

effects from the switchover. Leader formats and message types are not

changed. On the other hand, the statistics package has been

extensively modified, and the NMC has been notified of these changes.

The Very Distant Host option will also be included in this new system

release, and it is expected to be activated for use about June 1. The

detailed changes to the IMP system will be described in a forthcoming

revision to BBN Report 1822.

Finally, your patience is requested if the new system causes

unforeseen problems.

JMcQ/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   ]

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