==== transport_protocol_descriptor

Defined by DVB in <<ETSI-101-812>>.
Must be in an AIT (table id 0x74).

[source,xml]
----
<transport_protocol_descriptor transport_protocol_label="uint8, required">

  <!-- Only one of the following shall be present -->
  <!-- For protocol id 1: -->
  <object_carousel
      original_network_id="uint16, optional"
      transport_stream_id="uint16, optional"
      service_id="uint16, optional"
      component_tag="uint8, required"/>

  <!-- For protocol id 2: -->
  <ip_mpe
      original_network_id="uint16, optional"
      transport_stream_id="uint16, optional"
      service_id="uint16, optional"
      alignment_indicator="bool, required">
    <!-- One per URL -->
    <url value="string, required"/>
  </ip_mpe>

  <!-- For protocol id 3: -->
  <http>
    <!-- One per URL -->
    <url base="string, required">
      <!-- One per URL extension -->
      <extension value="string, required"/>
    </url>
  </http>

  <!-- For other (unknown) protocol ids: -->
  <protocol id="uint16, required">
    Hexadecimal content.
  </protocol>

</transport_protocol_descriptor>
----
