And interesting document that might prove helpful to some.
it has lots of interesting things in there on how the dvb services work i havent had time to look through the entire document but you guys might like it.
Its entitled "The Transport of DVB services over IP"
and the link for it is here
http://broadcasting.ru/pdf-standard-specifications/internet%20protocol/a086.tm3022r1.sb1338r1.tm-ipi10227r07.ipi%20handbook%20text.pdf