Large Data Transfer Service Context

<body topmargin=0 leftmargin=0 marginheight=0 marginwidth=0> <table cellpadding=0 cellspacing=0 border=0><tr> <td valign="top" colspan=2 height=110 BGCOLOR="#777777" TEXT="#080000"> <div> <B><IMG SRC="0097c660.gif" border=0 width="124" height="102" ALIGN="RIGHT" HSPACE="0" VSPACE="0"></B></div> <div> <FONT SIZE="6" COLOR="#FFFFFF" FACE="Arial" ><B>Large Data Transfer Service Context</B></FONT><B>     |     </B><A HREF="index.htm" TARGET="_top" TITLE="HighLevel Design Specification"><U><B>home</B></U></A></div> <div> back to<B>  </B><A HREF="id4.htm" TARGET="_top" TITLE="Large Data Transfer Service Design"><U><B>Large Data Transfer Service Design</B></U></A></div> <div> </div> </td> </tr><tr> <td valign="top" width=210 BGCOLOR="#777777" TEXT="#080000"> <div> <B>Large Data Transfer Service Context</B></div> <div> <A HREF="id11.htm" TARGET="_top" TITLE="Large Data Transfer Receiver Protocol"><U>Large Data Transfer Receiver Protocol</U></A></div> <div> <A HREF="id12.htm" TARGET="_top" TITLE="Large Data Transfer Transmitter Protocol"><U>Large Data Transfer Transmitter Protocol</U></A></div> <div> <A HREF="id13.htm" TARGET="_top" TITLE="Large Data Transfer Decomposition"><U>Large Data Transfer Decomposition</U></A></div> <bR> </td> <td valign="top" height=370 BGCOLOR="#FFFFFF" TEXT="#080000"> <div> When an instance of the large data transfer service is to be integrated in the OBOSS-III framework is to replace the telecommand and/or telemetry routing facilities inherently associated to an application process.</div> <div> The inclusion of an instance is depicted below.</div> <bR> <div> <IMG SRC="02270240.gif" border=0 width="1136" height="1060" ALT="Context Diagram" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></div> <bR> <div> The similarity between the service data unit and a normal TC/TM packet makes it possible to make the large data transfer service transparent to the application processes/services using it.</div> <div> The usage of the receiving sub-service is selected on application process level, where as the usage of the sending sub-service is selected on application process or service level.</div> <div> If the large data transfer service is used by an application process/service it shall be possible for it to create TM packets whose entire length exceeds the mission constant TMPKT_MAX_LENGTH (an SDU TM). When the SDU TM packet is routed through the large data transfer, it will be transformed into a service data unit and downlinked in service data unit parts TM packets.</div> <div> When a service data unit is uplinked to an application process/service using the large data transfer service the parts are automatically assembled into a service data unit. The service data unit is transformed into a TC packet (SDU TC), with an entire length that can exceed the mission constant TCPKT_MAX_LENGTH. The SDU TC packet is forwarded to the destination process via the application process dispatcher.</div> <bR> <bR> </td> </tr></table></body>