TPEG Encryption Tables

In TPEG, technology provides means to encrypt or otherwise modify (e.g. compress) large parts of the data volume contained in TPEG transport frames. Encryption or modification can proceed on two levels within TPEG: complete service frames or individual service component frames.


Encryption of TPEG Service Data Frame

 

As specified in the TPEG Service Framework (ISO/TS 21219-5), the encryption on a service frame level  uses a Service Encryption Indicator (ServEncID).

 

The ServEncID is an unsigned Integer value with range 0-255. If the indicator has a value 0 all data in the Service Component Multiplex are non-encrypted. Every other value of the Service Encryption Indicator indicates that one of several mechanisms for data encryption or compression has been utilised for all data in the following multiplex data. The encryption/compression technique and algorithms may be freely chosen by the service provider from available standardised options or alternatively from proprietary methods. The encoding of the method chosen is as follows:

  • 0 = no encryption / compression
  • 1 to 127 = reserved for standardised methods. The current list of already allocated ServEncID by TISA is shown below
  • 128 to 255 = may be freely used by each service provider, may indicate the use of proprietary method 
ServEncID Standardized method
 TISA Reference doc.
1
 
...

107 ZLIB Compression SP100xx
...    
127

 

 

Encryption of TPEG Service Component Frame

 

As specified in the TPEG Service and Network Information (ISO/TS 18234-2), the encryption on a service component level uses an Encryption Indicator (EncID).

 

The EncID is defined as one byte according to TPEG primitive syntax. If the indicator has a value 00 hex all data in the component multiplex are non-encrypted. Every other value of the encryption indicator indicates that one of several mechanisms for data encryption for data encryption and compression has been utilized for all data in the following data multiplex. The encryption/compression technique and algorithms may be freely chosen by the service provider from available standardised options or alternatively from proprietary methods. The encoding of the method chosen is as follows:

 

  • 0 = no encryption / compression
  • 1 to 127 = reserved for standardised methods. The current list of already allocated EncID by TISA is shown below
  • 128 to 255 = may be freely used by each service provider, may indicate the use of proprietary method

     

     

    EncID Standardized method
    1

    ...

    127