Conditional access (CA) lets viewers choose what to watch from
thousands of programs at the touch of a button. This pay per view
technology also lets parents block shows and games the don't want their
kids to watch. All thanks to the little top boxes that sit on their
television sets. This non technical article presents conditional access
for home viewing.
Satellite Broadcasts - Conditional Access
Conditional Access enables broadcasters to block programs from some
viewers and charge others to see the show. Broadcast options such as
pay-per-view (PPV), video-on-demand (VOD) and broadcast video are all
based on conditional access technology. The basis of conditional access
technology rests on scrambling and descrambling the pictures on your
screen. Just as important is entitlement and entitlement management to
determine which viewers are permitted to the see the show and block
other viewers.
Satellite digital TV - Conditional Access
While digital TV and conditional access seem to have been here forever,
they are relative new comers compared to movies. The conditional access
digital TV standards were first finalized in 1993. Since then,
conditional access enables broadcasts and billing for satellite
broadcasters, cable and terrestrial stations. Satellite Digital TV
stations are major conditional access users and vital to their
financial growth and product development.
Scrambling / Descrambling - Conditional Access
Conditional access is the gate keeper that lets subscribers see the
show and makes the show incomprehensible to unauthorized users.
Entitlement checking takes place simultaneously with the broadcasting
of the show controlled by the conditional access gate keeper. The show
broadcast also includes encrypted codes - “Control Words” - to enable
the descrambling for authorized viewers with conditional access
permission. These codes are sent inside dedicated messages called
entitlement control messages for the “top box” on your TV set to
decode.
Entitlement Management - Conditional Access
The entitlement management function consists of distributing
entitlements to receivers. There are several kinds of entitlements that
match different levels of subscriber service: As we all know, the most
popular are monthly and pay per view. This info is sent inside
dedicated messages entitlement management messages and Shazam! There’s
the show you wanted to see, now all you need is a cold drink, popcorn
and some friends to enjoy the show.
