Quote:
Originally Posted by zantarous
Why does cable need to rely on encryption, surely with a true return path cable companies should be able to tell paying customers from ones that are using dodgy boxes?
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Because it's still a broadcast technology, not unicast.
The cable that comes into your house is shared, it's not a direct 1-to-1 connection, you take a tap off the same cable as your neighbours. So anything sent to you, is also sent to people in same neighbourhood who share the same cable.
This means that even if the platform was upgraded to a switched video system, where channels are only sent on request people with dodgy boxes could still watch channels that others within the same area have tuned to.
Even now with VOD, if you have a dodgy box you can tune to the VOD streams that are being used in your area and watch them. It's not that useful with VOD because you're reliant on someone watching what you want to watch when you want to watch it, but if all linear TV was delivered in the same way using SDV then you'd find the boxes were quickly upgraded to be able to view whatever channels are currently being sent to the area.
There has to be some sort of encryption on the wire to stop people taking advantage of that, you can only stop the boxes from using the return path to request channels, you can't stop them listening in on the cable for any that are being sent down it.