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Network Working Group Alex McKenzie RFC #374 BBN NIC 11099 19 July 1972

There are two significant developments in the operation of the network which should be of interest to all sites:


 On Tuesday July 18, the new IMP software described in previous RFC's
 (#331,#343,#359) was apparently successfully released.  We ran from
 10:00am on that day until Wednesday afternoon with very few network
 problems attributable to the new system.  We are quite pleased with
 this performance, and expect to leave the new system up permanently!!
 We are, of course, aware that in any system of this size, bugs may
 crop up at any time, and we solicit the help of the network community
 in finding them.  We also believe that the new system may have a
 different "feel" to users, both terminal users and Hosts.  We urge
 everyone to have a bit of patience while getting used to any change in
 the "feel" of the network.  On the other hand, PLEASE REPORT ANY
 Evidence of bugs, guesses as to what went wrong, etc., are always
 useful in hunting bugs, but don't let the lack of positive proof delay
 the reporting of suspected system malfunction.  The NCC telephone
 number is (617) 661-0100.  Feel free to call collect!
 The one known shortcoming of the new software is the exacerbation of a
 long-standing TIP software problem.  The TIP now often appears to
 neglect sending an Allocate control message for some active
 connection, with the effect that the Server-to-User path becomes
 blocked.  We are giving the solution of this problem the highest
 priority!  (Our current data seems to indicate that this problem is
 most likely to occur when there are several users and when the Server
 Host is a TENEX system.  If you know of other situations where this
 problem has occurred, please let us know!)
 Now that the new system is up, all sites with Model 516 IMPs will be
 contacted by telephone and asked to reset the switches on their IMPs
 as follows:
           HALT INH         - on
           W.D.T.           - on
           AUTO RSTRT       - on
           MEMORY PRTCT     - on
                                                              [Page 1]


 The network has recently been experiencing serious difficulties
 related to the annual problem of more demand for electricity than is
 available during the summer months.  For example:
     During the month of June, between 1/4 and 1/2 of the
     IMP down time was due to site power failure.
     During the weekend of July 15-16, two sites were down
     all weekend due to air-conditioning failure which was
     apparently related to power failures or brownouts.
     This left several sites connected to the rest of the
     net through only one path which, according to Murphy's
     law, eventually failed - leaving nine sites partitioned
     from the remainder.
     On July 18, an underground power transformer supplying
     power to the entire computer room at site 27 failed,
     putting IMP 27 out of action for several hours (anddit
     could easily have been several weeks.)
 Obviously in these cases there is little that either the NCC or the
 site can do to restore service.  We expect these situations to
 continue or even get worse as the summer continues.  Please try to
 restrain your annoyance when these situations arise; we don't like
 them either!
     [ This RFC was put into machine readable form for entry ]
     [ into the online RFC archives by BBN Corp. under the   ]
     [ direction of Alex McKenzie.                      1/97 ]
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/data/webs/external/dokuwiki/data/pages/rfc/rfc374.txt · Last modified: 1997/03/05 20:02 (external edit)