Network Working Group                                   Alex A. McKenzie
Request for Comments: 638                                        BBN-NET
NIC: 30538                                                April 25, 1974


                IMP/TIP Preventive Maintenance Schedule

      This RFC corrects numerous inaccuracies in RFC #633.  Rather than
      trying to list all the changes, I urge all Liaisons and other
      interested parties to look carefully at the times now listed for
      the sites they are interested in.

   This note presents the current IMP/TIP Preventive Maintenance
   schedule.  Preventive Maintenance is scheduled on a monthly basis and
   a given machine is normally scheduled at the same time each month;
   wherever possible the time is chosen to coincide with the PM time for
   the Host(s) at the site.

   It is sometimes necessary to reschedule PM's because of network
   connectivity considerations or for other reasons.  Whenever this is
   necessary we will follow the usual procedure for scheduling down time
   with our "primary contact" at the site.  Permanent changes to the
   schedule will he announced via the RFC mechanism.

   PM's normally do not require the IMP/TIP to be taken down.  However,
   machines must be taken down in some cases, so no one should rely on
   the machine remaining available through the PM period.

   PLEASE REMEMBER THAT TUESDAY MORNINGS FROM 7am TO 9am ARE RESERVED
   FOR NETWORK SOFTWARE MAINTENANCE.


   All times shown below are Eastern Time.

    First Monday (of each month)

         5 BBN IMP  [0830-1130]

        40 NCC TIP  [1130-1430]

        47 WRIGHT-PATTERSON  [1300-1700]

    First Tuesday

        30 BBN TIP  [0830-1130]

         3 UCSB  [1130-1430]




McKenzie                                                        [Page 1]


RFC 638         IMP/TIP Preventive Maintenance Schedule       April 1974


    First Wednesday

        14 CARNEGIE  [0830-1130]

         2 SRI [1200-1500]

    First Thursday

        26 SDAC  [0830-1130]

         4 UTAH  [1030-1330]

        41 NORSAR  [0830-1130]

        42 LONDON  [0830-1130]

    Second Monday

         6 MIT-MAC  [0830-1130]

        44 MIT-IPC  [1200-1500]

        25 DOCB  [1030-1330]

    Second Tuesday

        17 MITRE  [0830-1130]

        23 USC [1130-1430]

    Second Wednesday

        31 CCA  [0830-1130]

        11 STANFORD  [1200-1500]

        32 XEROX  [1400-1700]

        18 RADC [0900-1200]

    Second Thursday

        27 BELVOIR  [0830-1130]

        35 UCSD  [1130-1430]

        37 RML  [0930-1230]




McKenzie                                                        [Page 2]


RFC 638         IMP/TIP Preventive Maintenance Schedule       April 1974


    Second Friday

        43 TYMSHARE  [1200-1500]

    Third Monday

         9 HARVARD  [0830-1130]

         1 UCLA  [1000-1300]

        48 KIRTLAND  [1600-1900]

    Third Tuesday

         7 RAND  [1130-1430]

         8 SDC  [1530-1830]

    Third Wednesday

        12 ILLINOIS [0930-1230]

        28 ARPA  [1700-2000]

        15 AMES IMP  [1200-1500]

        16 AMES TIP  [1300-1600]

        36 HAWAII  [1430-1730]

        45 MOFFETT  [1400-1700]

    Third Thursday

        20 ETAC  [0830-1130]

        33 FNWC  [1300-1600]

    Third Friday

        21 LLL  [1230-1530]

    Fourth Monday

        13 CASE  [0830-1130]






McKenzie                                                        [Page 3]


RFC 638         IMP/TIP Preventive Maintenance Schedule       April 1974


    Fourth Tuesday

        19 NBS  [0830-1130]

    Fourth Wednesday

        10 LINCOLN  [0830-1130]

        46 RUTGERS  [1000-1400]

    Fourth Thursday

        24 GWC  [1500-1800]

        22 ISI  [1300-1600]

        29 ABERDEEN  [1300-1600]











       [ This RFC was put into machine readable form for entry ]
       [ into the online RFC archives by Alex McKenzie with    ]
       [ support from GTE, formerly BBN Corp.           2/2000 ]




















McKenzie                                                        [Page 4]