Recommendation X.350

GENERAL INTERWORKING REQUIREMENTS TO BE MET FOR DATA TRANSMISSION
        IN INTERNATIONAL PUBLIC MOBILE SATELLITE SYSTEMS


       The CCITT,

considering

       (a)  that a maritime satellite service is being operated  by  the
International Maritime Satellite Organization (INMARSAT);

       (b)  that data transmission services in the INMARSAT system should meet the 
provisions laid down for data transmission in general;

       (c)  that the mobile DTE may be connected to a PDN on a call-by-call basis;

       (d)




1.5

1.6

       Aeronautical earth station is defined in Article 1,  4.20 of  the  Radio
Regulations, ITU, Geneva 1982.

       Land earth station is  defined  in  Article  1,    4.10A  of  the  Radio
Regulations, as modified by MOB-WARC 1987.

       Base earth station is  defined  in  Article  1,    4.11A  of  the  Radio
Regulations, as modified by MOB-WARC 1987.

1.7    xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx












Note - The rest of this Recommendation applies to public maritime satellite data 
transmission systems. Its applicability for public aeronautical and land  mobile
satellite systems is for further study.






















2.     Note 1 in section 3

       Note 1 - Since a maritime satellite telephone circuit is used for accessing 
the maritime PAD, charging of the call may take place until the circuit has been 
cleared forward (see the  Q.1100-Series  of  Recommendations  for  the  relevant
conditions). For calls set up from the on-board DTE, disconnection by the maritime 
PAD corresponds to clearback on the maritime satellite  telephone  circuit.  The
clearing procedures related to clearback of telephone circuits in  the  maritime
satellite service are defined inthe Q.1100-Series of Recommendations.