Recommendation U.63
                       GENERAL REQUIREMENTS TO BE MET IN INTERFACING THE INTERNATIONAL
                          TELEX NETWORK WITH THE MARITIME "DIRECT PRINTING" SYSTEM
                                    (Malaga-Torremolinos, 1984)
               The CCITT,
         considering
               (a) that it is desirable that the interface between the international telex
                  servi            maritime    "direct    printing"     system     be
         defined;
              (b)   that the  CCIR  is  charged  with  the  task  of  making
         Recommendations relating to the radio path;
              (c)   that explanation of the details of the interface between
         the international telex network and the maritime "direct  printing"
         system      would      be      of      assistance      to       the
         CCIR,
         unanimously recommends
               that  the  following  points  should  be  taken  into  consideration   when
         interfacing the maritime "direct printing" system to the telex network:
         1      General
         1.1    The maritime "direct printing" system should be capable of interfacing the
         international telex network in one or more ways:
               -   in accordance with Recommendations  U.1,  U.11  and  U.12  for  direct
                  real-time operation,
               -   in accordance with Recommendation F.132 for ship originated access  to
                  maritime store-and-forward units,
               -   in accordance with procedures defined in Series F and U Recommendations 
                  for store-and-forward access by terrestrial subscribers.
         1.2    Answerback signals from the ship should be obtained both at the  beginning
         and at the end of the call. When such signals  are  transmitted  into  the  telex
         network, the coast station should make sure that they consist of  20  consecutive
         characters and are sent at cadence speed.
               The answerback should be in accordance with Recommendation F.130.
         1.3    If the coast station detects an end of telex message signal from the ship,
         the existing terrestrial connection (if any) must  be  cleared  down  and  a  new
         connection established for the next telex message. This should  apply  also  when
         the next message is intended for the same terrestrial subscriber.
         1.4    For ship  originated  calls,  the  coast  station  should  be  capable  of
         returning to the ship any service codes received from the telex network.
         1.5    For land originated calls, service codes should be returned to  the  telex
         network in accordance with Recommendation F.131.
         2      Special conditions related to ship originated calls
         2.1    The selection signals received  from  the  ship  should  have  formats  in
         accordance with Recommendation F.60, S 3.2.2.
         2.2    When  accessing  a  maritime  store-and-forward  unit,  the  call  control
         procedures should be in accordance  with  the  relevant  Recommendations  in  the
         Series F and U.






















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         2.3    For direct access into the telex  network,  the  normal  telex  procedures
         given in Recommendations U.1, U.11 and U.12 should be  followed.  In  particular,
         the requirements given in these Recommendations with regard  to  the  sending  of
         selection signals, end of selection signals and class of traffic  signals  should
         be observed:
               -   Recommendation U.1, S 6,
               -   Recommendation U.11, SS 7 and 9,
               -   Recommendation U.12, S 3.5.
         3      Special conditions related to land originated calls
         3.1    For direct access from the telex network,  the  time-out  requirements  of
         Recommendation U.1, U.11 and U.12 should be observed:
               Types A and B signalling (Recommendation U.1)
               The time from the end  of  selection,  combination  No.  26  (+),  or  last
               selection character received and the return of the call  connected  signal
               should not exceed 60 seconds.
               Type C signalling (Recommendation U.11)
               The time taken from the end of selection signal, combination  No.  26  (+),
               to the call-connected signal should  not  exceed  60  seconds  (see  Table
               1/U.11, remarks relating to the call-connected signal).
               Type D signalling (Recommendation U.12)
               The time taken from the end of selection signal, CSC code No.  11,  to  the
               call connected signal should not exceed  90  seconds  (see  Recommendation
               U.12, S 3.11).
               Note - It should be noted that for types A, B and C  signalling,  the  same
         timings pertain to service signals (NP, NC, NA, OCC, etc.), and that in  addition
         for type D signalling  the  same  timing  pertains  to  the  last  backward  path
         signalling characters and terminating-through-connection.
         3.2    If the time-out requirements cannot be met, the coast  station  may  offer
         the calling subscriber, by an appropriate service code, a store-and-forward  unit
         for forwarding the call to the ship.
         4      Maritime group calls
               The provisions given in Recommendation U.62, S 4 apply.





































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