Thursday, February 16, 2012

Technical overview

CableCARD is a appellation trademarked by CableLabs for the Point of Deployment (POD) bore authentic by standards including SCTE 28, SCTE 41, CEA-679 and others. The CableCARD is physically a PCMCIA blazon II PC card, supplied by the cable company, which is amid into a aperture in the host (typically a agenda television set or a set-top box) in adjustment to analyze and accredit the customer, and to accommodate proprietary adaptation of the encrypted agenda cable arresting after the charge for a set-top box. The cable tuner and QAM demodulator themselves are allotment of the host device, as is the MPEG decoder. The role of the agenda is to accomplish any codicillary admission and decryption functions. This after-effects in an MPEG-2 carriage stream, which is decoded by the host. The agenda aswell receives letters beatific over the out-of-band signaling approach by the cable company's Head end servers and assiduously them to the host.

Cards from above providers such as Comcast, Cox Communications, RCN and Time Warner Cable in some regions currently crave on-site accession by a technician, who letters the different ID numbers pre-assigned to both the CableCARD and the agenda television to the aggregation headquarters, area they are adapted to the customer's account. Because of this, CableCARDs cannot be confused from one accessory to addition after a appointment from a cable aggregation installer. Some regions (such as Comcast Houston) do acquiesce chump installs, and in fact accommodate appropriate buzz abutment for CableCARDs. The agenda is amid as users do for laptop PCMCIA cards. The CableCARD identification numbers are accustomed to the abettor who again sends the CableCARD an out of bandage Entitlement Management Message (EMM), which accidentally programs the CableCARD, acceding it to break for the specific host alone those shows and casework which the user is accustomed to view. 1 2 3

CableCARDs with claimed computers:

Existing dent cable set-top boxes accomplish four basal functions:

Enable accepting and selecting agenda and analog cable channels

Uniquely analyze the chump and accredit the appearance to which they accept subscribed

Break accolade agenda channels and exceptional programming such as cine channels

Accommodate alternate two-way communications for:

Alternate programming guides

Pay-per-view

Video on Demand

Switched video streams

New agenda televisions and added accessories that are labeled DCR (Digital cable ready) contain:

congenital abutment for accepting agenda cable channels (via an centralized QAM tuner)

a aperture for the accepted adaptation of CableCARD (see photo here), which allows decryption of encrypted agenda channels.

The CableCARD 2.0 blueprint includes abutment for #1-4, alternate two-way communications; about it is alien absolutely if CableCARD 2.0 hosts and accordant servers will become available. Approaching accessories which abutment CableCARD 2.0 are accepted to be labeled iDCR "Interactive agenda cable ready". Among added requirements, CableCARD 2.0 hosts will be appropriate to accommodate the OpenCable Application Belvedere (OCAP), aswell accepted as Tru2Way, to run programs downloaded from the cable company. Some analysts adumbrate that advanced availability of tru2way will not be apparent until astern 2010.

An another to CableCARD 2.0, a lot of afresh advocated by the U.S. cable television industry, uses Downloadable Codicillary Admission Arrangement (DCAS) in abode of concrete CableCARDs. In this proposal, a custom aegis dent have to be anchored into every adjustable host; if a aegis arrangement is compromised, a new aegis affairs can be downloaded to the host device.

Because the codicillary admission arrangement is in software, it can be beatific with the video as a anatomy of Agenda Rights Management (DRM). The CableCARD Host Licensing Acceding (CHILA) and the DCAS acceding bind the technologies that CE companies may use for distributing video from host devices. CE companies commodity to this accretion the angle of CableCARD arrangement aegis issues to aswell cover agreeable aegis issues. They adopt to accord with agreeable owners anon with their standards and attention cable aggregation protocols and formats as a carriage only. CE companies ambition to acquaint video central the home arrangement application their own adequate protocols and formats.

The OpenCable Application Belvedere (OCAP) is a Java-based belvedere advised for use either with any aegis admission arrangement — whether it is CableCARD 2.0 accessories or approaching downloadable aegis schemes. OCAP was angry to CableCARDs because, as it was absurd by CableLabs, the added processing all-important for managing the advice with the cable aggregation server would be performed, not on the cable aggregation provided accessories (the CableCARD), but on the customer electronics accessory — accepted as the CableCARD "Host". CE companies objected that OCAP is accidental for the simple assignment of managing two-way communications on the cable networks. The CEA angle is that Java is not able for CE devices, and that cable companies are casual to CE manufacturers the costs of a software belvedere which they didn't need, and which will not run on their absolute accouterments architectures.

The customer electronics industry proposed in November 2006 that the CableCARD 2.0 blueprint be upgraded to cover the accouterment for adapted MCards that would abutment the communications all-important for VOD, PPV, and Switched Video. This agenda would be astern accordant with earlier cards, and abutment would be appropriate for them on cable aggregation servers by January 2008. These adapted MCards would not acquiesce two-way advice application accepted OCURs, which, by definition, are unidirectional. This alleged "OCAP-less" angle was alone by the NCTA for a array of affidavit abundant on in the issues articulation of this article. The abstruse advantage is that abundant beneath is affected about the accretion adequacy of the host, acceptance the accomplishment amount to be decidedly reduced. The disadvantage is that the MCard will be hardly added expensive, but the host will not necessarily be able to abutment the envisioned ecommerce and cyberbanking applications. CE companies altercate that such a agenda fulfills the 1996 law's claim that cable companies acquiesce two-way advice on their networks, and that OCAP fulfills abstruse goals far in balance of those all-important for such two-way communications.

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