Recommendation U.43
                                   FOLLOW-ON CALLS
                      (Malaga-Torremolinos, 1984; amended at Melbourne, 1988)
               The CCITT,
         considering
               that users of the telex  service  often  have  several  messages  ready  to
         transmit at the same time to different subscribers and that it would therefore be
         an advantage for them to be able to transmit these messages one after the  other,
         keeping the part of the communication  chain  already  established  in  a  seized
         condition and having the calls set up successively, without having to go  through
         the whole procedure of setting up a new call for each message,
         unanimously recommends
         1      that Administrations should be able to offer the possibility of  follow-on
         calls to their subscribers;
         2      that the procedure and control of such calls are the responsibility of the
         originating country;
         3      that if the originating country is not able to provide  this  facility  to
         their subscribers, the terminating  country  only  could  perform  the  follow-on
         function taking into account the following restrictions:
         3.1     that  the  Administration  of  the  terminating  country   offering   the
         possibility of follow-on calls shall take all the necessary steps to prohibit the
         use of this arrangement for setting up calls in transit to a third country;
         3.2    that the chargeable duration for the caller shall be the whole  time  from
         the moment when the first call is set up to the  moment  when  the  last  one  is
         terminated, the duration of the  intermediate  dialling  being  included  in  the
         chargeable duration;
         4      that if the alternative in S 3 is offered,  the  procedure  should  be  as
         follows:
         4.1    the caller in the originating country wishing to make  a  new  call  to  a
         subscriber in the terminating country shall indicate his wish to do so by sending
         a signal consisting of a special sequence made up of  four  combinations  No.  12
         (LLLL); usage of a fifth or more Ls is a national matter. This combination should
         be recognized in letter shift mode only;
         4.2    the terminating international exchange must be able to detect the  signal,
         to which it shall reply by sending the proceed  to  select  sequence  (e.g.  GA),
         inviting the caller to indicate the new number to be called;
         4.3    the caller shall transmit the new number to be called, and the call  shall
         then be set up in the terminating country in accordance with the usual procedure;
         4.4    the originating network shall ignore this new dialling  and  shall  simply
         keep the connection seized as if the first call were being continued.





























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