Security

For those of you with cable TV service, for some time now you've been witnessing the slow transition of cable TV from a pure analog service to a pure digital service. With cable systems finally at their limits for bandwidth, within the last year the cable companies have finally begun what has been dubbed the "analog reclamation" - removing analog channels from their service and replacing them with digital versions that require 1/6th (or less) the bandwidth. Because the reclamation involves removing analog versions of most for-cost channels (what's commonly called the Expanded Basic tier), the reclamation has been tied with the deployment of Digital Transport Adapters - low-cost cable boxes that are little more than a basic QAM tuner attached to an RF modulator. This has allowed cable companies to reclaim this space without deploying otherwise very expensive Set Top Boxes to every TV at an affected household. A side effect of this has been that computer TV tuner users, such as HTPC owners who in the analog age were accustomed to getting access to the EB tier on their computers with a simple analog TV tuner, were able to access those same channels in their digital form using ClearQAM-capable tuners. This is because the FCC mandated that the security mechanism be separate from the STBs, which gave rise to the continually problematic CableCARD. In the name of cost, DTAs do not have the ability to use CableCARDs, and as such do not meet the separable security requirements. Ultimately this required cable operators to put the digital versions of their EB tiers in the clear if they wanted to use DTAs, and this is why ClearQAM tuners can exist in a useful manner.

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