Network Working Group J. McQuillan RFC #331 BBN-NET NIC #9924 19 April 1972 Category: B.1 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 ] [Page 1]