1) All pictures/diagrams and tables copyright belongs to SCM.
2) Information provided here are for reference purpose and is not in anyway represents the individual vendors' viewpoint.
3) This proposal has no commercial value and only serves as a recommendation document.
4) The technical support for the respective devices mentioned in this document should be sought with the corresponding vendors.
Common Interface (CI) Implementation Proposal
Many digital broadcasters are adopting a variety of Conditional Access (CA) to protect their
content when broadcasting through the digital mean. Viaccess, Iredeto, Conax and
NagraVision are among the popular CA system adopted by broadcasters worldwide. Regional
presence and commercial incentives from the different CA vendors affects the digital
broadcaster's adoption policy. A good example would be the India Cable box market. Figure
1 shows the affiliation of the different broadcaster operators and the CA vendors.
Figure 1 India CAS system for different broadcast operators
For set-top box (STB) manufacturers, this causes difficulty for them to access the
broadcasters as they have to prepare different version of CA boxes for different broadcasters.
CA also adds complexity in the software design of the STB. This will cause more engineering
manpower as well as development cost to the STB.
Common Interface provides an intermediary solution. Common Interface adopts an external
chipset that is connected to a PCMCIA reader. A smart card (or CAM module) provides the
"key" to unlock the scramble signal that will be read by the PCMCIA reader. For different
CA, a different smart card will be used to address the descrambling issue. This solves the
complexity of the software development as well as eliminating the need to develop different
This proposal is based on the CI solution of SCM (r
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