RE: Question on ANNEX A: Informative Appendix

Thanks for the answer Mr. William StanisLaus.

Best Regards,

Simon Teh

Universiti Sains Malaysia

From: owner-ipdvb@erg.abdn.ac.uk [mailto:owner-ipdvb@erg.abdn.ac.uk] On Behalf Of William StanisLaus
Sent: 29 April 2005 02:26
To: 'Ip-DVB'
Subject: RE: Question on ANNEX A: Informative Appendix - SNDU Packing Examples

Hi Simon,

The Length specified in the example is SNDU length and NOT MPEG2-TS header length, as the ULE draft specifies one SNDU can prolong/extend more than one MPEG2-TS packet (that’s what this example trying to explain). In this example complete MPEG2-TS header information are not discussed, only PUSI and if PUSI is ONE payload pointer are discussed.

-William.

From: owner-ipdvb@erg.abdn.ac.uk [mailto:owner-ipdvb@erg.abdn.ac.uk] On Behalf Of Simon Teh
Sent: Thursday, April 28, 2005 5:45 PM
To: Ip-DVB
Subject: Question on ANNEX A: Informative Appendix - SNDU Packing Examples

Dear members,

I’m quite confusing with the example shown in Annex A on the examples of SNDU packing.

Example A.1: Two 186B PDUs.

     SNDU A is 200 bytes (including the ULE destination NPA address)

     SNDU B is 200 bytes (including the ULE destination NPA address)

   The sequence comprises 3 TS Packets:

                      SNDU

           PP=0      Length

   +-----+------+------+------+-   -+------+

   | HDR | 0x00 | 0x00 | 0xC4 | ... | A182 |

   +-----+----*-+-*----+------+-   -+------+

   PUSI=1     *   *

              *****

For the SNDU Length shown in the figure above, why it is 0xC4?

The size for a MPEG-2 TS packet is 188, if minus TS header and PP, is 183 bytes.

So the maximum size that the IP packet (SNDU A) can be encapsulated should be 183 = 0xb7,

But why it is 0xC4 instead of 0xb7? Or Do I miss something?

Hope somebody could help me on this matter. Thanks in advance!

Best Regards,

Simon Teh

Universiti Sains Malaysia