Telent运营商主要的私有描述子包括：
Download _descriptor
Table_timeout: Download table timeout in seconds. Default Value= 60 secs results in 0x003C
Magic_ID: Identification of the operator. Default Value=TELE results in 0x54454C45
Unique_Download_ID: Unique download identifier that allows to distinguish different downloads broadcast on one PID and TID.
Default value= 0x1234
HW_Version: Primary HW identifier. Along with HW_Subversion describes a particular HW version.
HW_Subversion: Secondary HW identifier. Along with HW_Version describes a particular HW version.
SW_Version: SW version identifier. It describes the current decoder code as well as the download software version.
Customer_ID : customer identifier. Default value = 0x23
SDB_descriptor
Semantics for this descriptor:
SDB_flag: Indicates if this TS contains switched services or not. 1 means switched, 0 means not switched.
Reserved_for_future_use: all bits set to 1
Service_info_descriptor
Extended_service_info_descriptor
