Common Interface - Standards

Standards

The normative DVB-CI standard EN 50221 was defined in 1997 by CENELEC, the European Committee for Electrotechnical Standardization.

According to the Common Interface scheme:

  • host : A device where module(s) can be connected; for example, an Integrated receiver/decoder (IRD), a VCR, a PC ...
  • module : A small device, not working by itself, designed to run specialised tasks in association with a host; for example, a conditional access sub system, an electronic program guide application module, or to provide resources required by an application but not provided directly by the host.

The specification only defines two aspects, two logical interfaces to be included on the same physical interface. The first interface is the MPEG-2 Transport Stream. The link and physical layers are defined in this specification and the higher layers are defined in the MPEG-2 specifications. The second interface, the command interface, carries commands between the host (receiver) and the module.

The specification does not define the operation or functionality of a conditional access system application on the module. The applications that may be performed by a module communicating across the interface are not limited to conditional access or to those described in this specification. More than one module may be supported concurrently.

The common interface shares many features of the PC Card Standard (PCMCIA). By reducing the widths of the address and data busses it has been possible to include a bi-directional parallel transport stream interface.

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