rso/rec JTC1/SC2/WG11
`
`CODING OF MOVING PICTURES AND ASSOCIATED AUDIO
`
`ISO/IEC JTC1/SC2/WG11
`MPEG 92/ 75H‘
`November 1992
`
`Title: Requirements and Method for High-level Multiplexing of MPEG and other
`Digital Service Bitstreams With Universal Transport Layer
`Anthony J. Wasiiewski, Scientific-Atlanta
`Contribution to MPEG Systems for MPEG-2 System Development
`
`- Source:
`
`Purpose:
`
`1 ABSTRACT
`
`This note presents an overview of the requirements
`and processes
`for multiplexing
`and
`providing
`transport
`and conditional access
`in a Digital
`Compression Services Delivery System (DCSDS).
`it
`considers an array of application domains that
`address numerous business segmentsand recognizes
`a plurality oi digital services that include lull motion
`video, tiim. audio. teletext and character/binary data.
`Basic multiplexing requirements. techniques and a
`suggested method of transmitting a multiplicity of
`services. including MPEG bitstreams and entitlement
`information via a Transport Layer are discussed.
`
`2 APPLICATTON DOMAINS
`
`Any practical approach for a DCSDS must take into
`account the nature of the transmission media and the
`decoding environments of the intended application
`domains.
`in particular. the design of the system must
`promote economical implementation of the decoders
`by shifting complexity into other parts of the hardware
`solution; this usually means the encode device(s) or
`other parts of the transmission network. The system
`
`design must also be heavily influenced by the needs
`of the end users (consumers) of the payload signals
`
`the transmission approach must support
`Further.
`routing of multiplexes of
`services as
`‘physical
`seamlessly as possflaie over multiple transmission
`media. with the ability to straightforwardly decompose
`the constituent data streams and recombine them in
`new combinations. all with hardware of minimal cost
`at lnterrnediary and endpoint nodes.
`
`This transmission flexibility must be coupled with a
`fully transparent and unifonn access method that
`allows adaptable and dynamic packaging of services
`in accordance with the (changing) business model of
`the network operator and the network itself.
`
`Figure 1 shows a typical system architecture in the
`CATV/D88 environment. As indicated. a layered
`approach ‘to multiplex construction, which includes
`compression, error-correction and conditional access T
`is possible.
`
`The DCSQS should embody a solution that functions
`lavorably in the following application domains:
`
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`

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`Wnliluwcld: Requirement: and Method tor High-Laval Multiplexing of MPEG and Other Digital Service Bitctuune With Univar-nlTunsport Layer
`
`2.1
`
`NTSC, PAL SECAM
`
`A primary requirement for a commercial DCSDS is the
`transport and subsequent decoding of conventional
`television signals which originate in the NTSC, PAL
`and SECAM iormats This must take into account the
`diverse display parameters found In these standards
`such as horizontal line rate. frame rate. number of
`scan lines per frame and color subcarrierfrequencles.
`ideally. the multiplexed data stream itself would run at
`rates which provide a common clock source that can
`be used by the decoders to reconstruct the specific
`rates and frequencies needed.
`
`The multiplex should also permit multiple modes of
`compression to be utrilzed for each analog standard
`and for the simultaneous transport of videos sourced
`from and displayed ior all the analog standards.
`
`2.2
`
`Digital Audio
`
`Of equal importance is the transport and decoding of
`a multiplicity oi digital audio signal
`standards.
`Standards exist which encode digitized audio at
`sampling rates of 32 Khz, 44.1 Kit: and 48 Khz The
`channel bit rates for these standards range from 64
`Kbps to 320 Kbps and in most cases must be
`synchronized with associated video programs.
`
`A number of applicable standards exist or are being
`developed, for example:
`-
`
`SEDAT i. ll - Scientific-Atlanta
`
`AC1 (ADM). AC2, AC3 — Dolby Labs
`
`‘
`
`Muslcam - Phillips
`
`2.3
`
`C-Band and Ku Band Satellite
`
`The DCSDS must be designed to accommodate
`transport over existing and future C-band (36 Mhz)
`and Ku Band (24 Mhz) satellites. The preferred
`modulation method is OPSK. These transmission
`systems are characterized primarily by a Gaussian
`noise distribution. but protection ior burst errors must
`also be considered.
`
`Because of variations in signal strength over the
`satellite footprint and a large range of equipment
`
`Scientific-Atlanta
`
`2
`
`sites,
`existing downllnk receive
`In
`parameters
`provision must be made for the DCSDS multiplex to
`be adaptable to varying receive margin requirements.
`These may cause the requirements for overall data
`rate and error correction to be divergent on a case-
`\
`by-case basis.
`
`2.4
`
`CATV, SMATV
`
`The existing installed base in lntematloml CATV plant
`presents a broadband transmission path that is very
`attractive tor consumer delivery of compressed.
`multiplexed entertainment/informational signals. RF
`modulation methods such as 16-QAM. 4-VSB and
`others provide or will provide commercially-viable
`means for transport of a large number (150 +) of"6. 7
`or 8 MHz channels. Each channel, has capacity to
`carry up to 10 compressed film/video sources with
`current compression techniques.
`
`Programmers and operators are already considering
`many new applications for the coming expanded
`channel capacity. Near Video-On-Dernand (NVOD)
`and Video-On-Demand (MOD). One-way interactive
`senrlces. Video Game delivery. ad insertion and Text-
`based News delivery typify the anticipated directions.
`
`Consumers want a large variety of services which are
`selectable in a simple and friendly manner with short
`signal acquisition times to accommodate ‘channel
`surfing‘. Electronic Program Guides (EPGs) will likely
`be needed to help the user in sorting through the
`greatly expanded service offerings. The user lntenface
`must be unifon-n and self-revealing even though a
`wide range of service types are available.
`
`Specialized Satellite Master Antenna TV (SMATV)
`applications, such as movie service distribution to
`hotels and hospitals, will present demands similar to
`those of terrestrial cable.
`
`2.5
`
`Broadcast/HDTV
`
`Because the broadcast HDTV standard selected by
`the us. FCC will likely be an all-digital one. a DCSDS
`must be able to carry such a standard for delivery
`over broadband media. like those listed above. The
`main requirement
`is
`that
`the payload bit
`rate
`supported must be in the 16 Mbps to 18 Mbps range.
`A provision for applying conditional access to the
`HDTV data stream should also be available.
`
`November 2. 1992
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`OpenTV Exhibit 1002 Page 2
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`

`
`ISO/IEC JTC1/SC2/W611. MPEG 92/
`
`2.6
`
`Direct Broadcast Satellite (DBS)
`
`Directly broadcasting to the home via C-band or Ku
`Band satellite channels is greatly augmented by
`compression technologies The leveraging factor of
`many services per channel is perhaps of even greater
`imponance than in the CATV case, since the cost of
`adding extra channels (transponders) is greater.
`
`The consumer issues are all very similar to those
`found in cable distribution.
`Decoder cost
`Is
`somewhat
`less critical
`than for home terminal
`conveners. but is nonetheless an important driver in
`the DBS business model.
`/
`
`Uncomplicated and cost-effective integration of the
`receive and decode functions is of primary importance
`in
`this
`application.
`Switchable decompression
`solutions in the decoder may also be of interest.
`
`2.7 Business Television and
`Videoconferencing
`
`Distribution of strategic. informational and training-
`orlented business information in video. audio and data
`formats. amongst geographically separate locations,
`is currently served with systems that multiplex digital
`and analog services. such as Scientific-Atlanta's B-
`MAC products. The migration to an all-digital system
`with the feasibility of a totally encryption-based
`security approach and. of course,
`the greater
`information bandwidth offered by compression, will be
`a natural one.
`
`Business Television (BTV) applications that call for live
`teleconferencing
`between
`potentially
`several
`geographically separate locations. bring specific
`access requirements in the area of point-to-point
`addressing, cross-networking and authorization churn
`that must be handled in a viable system design.
`In
`the large though. these BTV operations also share
`many of
`the
`characteristics oi
`the
`traditional
`entertainment delivery systems.
`
`2.8
`
`North American Digital Hierarchy and
`SONET/ATM
`
`is often noted that a convergence of television,
`it
`telephones and computers is underway. This will
`emphasize the need to transport compressed video,
`audio and data services in a common multiplex
`across not only the usual broadcast channels, but
`also over terrestrial channels conforming to the ANSI
`T1.t07-1988 Digital Hierarchy (DS1. DS3, etc.) and the
`ANSI T1.105-1991 Digital Hierarchy -Optical interface
`Rates (SONET). At the very least, scalability of the
`multiplex to at or near the specified overall channel
`rates is implied.
`
`These standards feature specific framing and stuff-bit
`patterns which a DCSDS multiplex will be called upon
`to confonn with.
`Timing
`or
`synchronization
`requirements within the DCSDS multiplex must survive
`any alterations in rate imposed by the telephony
`transmission standards. AsynchronousTransler Mode
`(ATM) provides the concept of an Adaptation Layer
`(AAL) lot this purpose and the CCITT is working to
`achieve a common segmentation and reassembly
`(SAR) layer for the 4 classes of services they have
`identified.
`
`ATM, whrie not yet a finalized protocol, has
`nonetheless already garnered considerable support
`and may very likely appear in LAN solutions even
`betore it emerges in a wider network arena it is a
`frame relay approach which uses fixed-length packets
`as its delivery mechanism. Mapping into this standard
`may be lrnportant for a DCSDS.
`
`2.9
`
`Worldwide Telephony
`
`Compatibility with standards such as the CCl'lT Rec.
`6.742 second-order multiplex and other related line
`rates is also required.
`
`2.10
`
`Traditional Data Networks
`
`While current medium-speed data networks such as
`Ethernet are not
`fully suited for
`transmission of
`compressed real-time video because of their non-
`deterministic access methods. multimediaapplications
`will drive the need for video and audio transmission
`over
`networks
`of
`computers
`inter-ofiice
`teleconferencing
`between
`ordinary
`PCs
`or
`workstations over high-bandwidth Fiber Channel
`
`Scientific-Atlanta
`
`3
`
`November 2. 1992
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`OpenTV Exhibit1002 Page3
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`

`
`Wuilewlldz Requirement: Ind Method lor High-Laval Multiplexing oi MPEG and Other Digital Service Bitstrurm WM‘! UnivnrulTranoport Layer
`
`(ANSI X:3T9.:3), FDDI and/or ATM-based LANs may
`become common
`
`The design of the DCSDS should anticipate its usage
`over such communication _channels.
`
`3 REQUIREMENTS
`
`domains
`application
`from the
`Considerations
`mentioned in § 2 lead to an assortment of technical
`requirements for the multiplex lonnat and transport
`strategy for the DCSDS. A practical implementation
`should take these requirements into account
`in
`providing a cost-effective solution.
`
`This section highlights the requirements for
`DCSDS.
`The concept of a ‘transport
`layer‘
`introduced.
`
`the
`is
`
`3.1
`
`separation at the Transport Layer from
`Services/algorithms
`
`The digital services and the compression algorithms
`that are used for their transmission wfll likely change
`and evolve with time. Whfle DCT-based video
`compression algorithms
`represent
`the currently
`preferred approach, investigation of wavelets, lractals.
`vector quantization and presently unknown methods
`may bring about advances that make their use
`appropriate and cost-lustified. indeed, new, currently-
`unlrnagined application domains may be better served
`by such compression approaches.
`
`the DCSDS must anticipate this
`The design of
`evolution and pemnlt a seamless and transparent
`changeover in the network. The multiplex.
`In fact.
`should accommodate the concurrent
`transport of
`multiple compression standards. both audio and
`video.
`
`in many cases, several services may be transmitted as
`an associated set; one video and many audio
`channels providing stereo pairs in several languages
`is an example.
`This associated set should be
`combined into a 'channelized' bitstream which can be
`‘de-multiplexed and routed as an independent entity.
`
`the same time. many applications will require
`At
`multiple channeiized services, conditional access.
`security and system data to be carried in a single
`multiplex. This latter data is. in the large. independent
`
`Scientific-Atlanta
`
`4
`
`of the service types and compression algorithms used
`lor the services.
`it
`is therefore desirable for the
`DCSDS bitstream to be constructed from:
`
`a) a high-level multiplexing strategy
`b) a transport layer
`c) channellzed service packages
`
`The transport layer is used as a universal vehicle for
`the conveyance of
`certain parameters
`of
`the
`multiplexing strategy, conditional access data streams
`and system inlorrnation.
`
`The transport layer describes the number and type of
`services that are carried in a multiplex and supplies
`the mechanism by which these services may be
`accessed.
`controlled and demultlpiexed.
`The
`transport
`layer may also provide‘certain system
`services such as operational teletext messages that
`decoders may access and display lor user interface or
`exception handling conditions.
`
`3.2
`
`oi multiplex
`independence
`transmission medium
`
`from
`
`The DCSDS multiplex must be oriented towards the
`end-consumer of the transported services. not solely
`to the technology or to the physical channel over
`which it is carried. This channel may vary. even along
`one
`end-to-end transmission path;--A-a - program
`originated at a C-band upiink may be received at a
`CATV headend and then sent directly through a
`terrestrial distribution plant to be decoded by a home
`tenninai in a subscriber premise. The distribution
`plant may have a fiber-optic trunking system and
`traditional coax cable thereafter.
`
`regionally-produced
`applications.
`other
`in
`programming may be backhauled over fiber-optic
`networks and then upllnked over Ku Band satellite
`transponders.
`
`The multiplex should be inexpensively and seamlessly
`routable over such network combinations and its
`
`‘subpans should be extractable at intermediatenodes
`without costly processing.
`
`3.3
`
`Error management optimized for
`transmission channel
`
`the
`
`Another
`
`requirement driven by the need for
`
`November 2, 1992
`
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`OpenTV Exhibit 1002 Page 4
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`

`
`lSOIlEC JTC1lSC2NVfS11. MPEG 92!
`
`independence oi the bltstream from the transmission
`medium, is the optimization oterror correction lor the
`physical channel.
`The degree and type of error
`correction/detection must
`deliver
`appropriate
`operational characteristics without burdening the
`system with undue overhead.
`
`Thus. error correction sufficient for the relatively low
`BEFls found on optical networks wfli not be suitable
`for CATV applications where burst error rates and
`powerilne-frequency-synchronized ingress may cause
`temporary signal loss due to the ‘cliff effect‘ ct digital
`systems.
`in CATV systems, nomtai operating
`procedures, such as the use of frequency sweepers
`for plant diagnostics are an expected source of
`channel noise. Error correction suitable to channel
`BEFls of 104 are required.
`,
`
`For C-band satellite, similar protection is called for,
`but in the Ku band the most powerful schemes are
`needed. because error rates are higher (to 2x10‘) and
`less predictable.
`
`3.4
`
`layered error correction trom
`Seamless,
`satellite to cable or other medium
`
`the various
`requirements of
`The differing error
`physical media oi interest. should be applied as
`layers or ‘sheaths’ that may be readily removed at
`boundaries between the media. This enhances the
`possibility of producing cost-efficient hardware for
`commercial applications at the DCSDS in situations
`where the payload signals must
`traverse a large
`number of media on their way to the end-user.
`
`1) Synchronization
`2) System Data, Encryption seeds,
`Multiplex control
`3) Conditional Access
`4) Utility Data
`5) Video/audio/teietext
`
`Conditional access data may require additional enor-
`fii_9§_ll§m 50 that packets which can not be fully error-
`corrected may be relected by the receive tenninal to
`be obtained later on a re-transmission.
`
`3.6
`
`Fast Acquisition time/cryptographic cycles
`
`The consumer demands fast signal acquisition times -
`at least for video. The practice of ‘channel surfing‘,
`that is, depressing either the increment or decrement
`key on the home terrninai
`remote control while
`watching the pictures go by.
`in order to make (or
`perhaps
`to
`avoid making!)
`a
`selection_
`is
`commonplace. At least in the U.S., consumer studies
`have shown that periods between picture lock-up‘that
`are longer than about 200 ms become annoying,
`while 500 ms periods are unacceptable.
`This
`presents a significant challenge in digital systems.
`
`The time required for acquisition. in the most general
`case. will be composed of:
`
`a) tuner slew
`b) de-multiplexing
`c) de-erroring
`cl) Seed delivery and decryption
`e) rate buffering
`f) l-frame sequence (if predictive coding)
`
`3.5
`
`Error management optimized to data type
`
`Within the context of a fixed overall channel error
`protection, parts of the bitstream may be more critical
`than others. Also. some parts of the bitstream wfli
`comprise a much smaller share of the bandwidth than
`others.
`thus allowing the overhead due to error
`correction to be larger.
`
`Assuming linear or non-linear PRBSs arenused to
`encrypt
`the
`basic
`service
`streams
`and that
`asymmetric. Private key cryptography is employed at
`other
`levels, such as seed encryption,
`the time
`needed to acquire and deliver the seeds tor the PRBS
`generators and the frequency with which the seeds
`are
`changed (cryptographic
`cycle) will be a
`deterrnlning factor ior signal acquisition speed.
`
`A hierarchy of error coding may be established which
`combines both of these principles. From highest to
`lowest protection, the hierarchy is:
`
`ll predictive video coding is used. it is most efficient
`to harmonize the cryptographic cycle and I-frame
`sequence.
`
`Scientific-Atlanta
`
`5
`
`November 2. 1992
`
`(cid:50)(cid:83)(cid:72)(cid:81)(cid:55)(cid:57)(cid:3)(cid:3)(cid:3)(cid:3)(cid:40)(cid:91)(cid:75)(cid:76)(cid:69)(cid:76)(cid:87)(cid:3)(cid:20)(cid:19)(cid:19)(cid:21)(cid:3)(cid:3)(cid:3)(cid:3)(cid:51)(cid:68)(cid:74)(cid:72)(cid:3)(cid:24)
`OpenTV Exhibit 1002 Page 5
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`

`
`W-Iiluweld: Requirement! and Method lor High-Level Multiplexing oi MPEG and Other Digital Service Bitctrurnc With Univorul Transport Layer
`Overall
`information
`.Fi%ilM_lI22.=’-J
`Ba.ta-
`
`$teI_ntlefl
`
`3.7
`
`HDTV compatibility
`
`As noted in 5 2. a digital HDTV standard is highly
`likely. The compressed bitstreams of the four ail-
`dlgital proposals should be considered as potential
`services to be carried over the variety of network
`types previously discussed.
`in fact, it is probable that
`the
`selected High-Definition
`standard may be
`commercially transmitted over satellite and CATV
`pathways before widespread over-the-air broadcast
`becomes available. A viable DCSDS will include the
`capability for this type of transport.
`
`The tour digital Advanced Television (ATV) proposals:
`Zenith [AT&T, ATRQ, ATA Dlglclpher, and ATA Channel
`Qmggtiglg Dgigipher, share many common features
`such as DCT-based and entropy coded compression.
`16:9 aspect ratio, motion estimation/compensation,
`frame . rate (59.94 Hz) and Reed-Solomon error
`correction. They differ in other areas such as their
`scanning
`systems
`(1050
`interface
`vs.
`787.5
`progressive), motion estimation techniques (block
`size, convergence method). DCT coefliclent coding
`techniques (ADPCM. vector, adaptive vector). channel
`modulation specifics (32-QAM, 2/4-VSB. 32-QAM dual
`carrier) and audio systems (Dolby AC-2, Musicam,
`MIT).
`
`The DCSDS should be able to treat the transport of
`these ATV signals with reasonable adaptations.
`Where mbced modulation modes are used, a single
`mode may be substituted. The data rates required
`(on the order of approximately 17 Mbps) should be
`accommodated.
`
`3.8
`
`Can be transmitted over standard circuit-
`switched TDM telephony multiplexes
`
`The North American Digital Hierarchy as defined in
`ANSI T1.107-1988. the CCITT (5.742 and its related
`standards
`and
`other
`international
`telephony
`multiplexes, specify discrete channel bit rates and
`relatively rigid framing and bit-stuffing rules to provide
`adjustabiiity lor
`rate-matching
`in
`time-division-.
`multiplexed (TDM) digital channels. Some example
`North American rates are:
`
`D81
`DS1C
`DS2
`DS3
`
`1 .544
`3.152
`5.312
`44.736
`
`1,535
`3,033
`5,175
`43,232
`
`The deployment penetration of any particular rate
`varies; D81 and D83 are the most popular. The
`capability of these multiplexes to combine voice and
`data over cost-effective leased lines may lead to a
`broader use of multimedia services in mainstream
`business telecommunication networks,
`if video can
`also be accommodated.
`
`Therefore. a DCSDS multiplex should be capable of
`running at rates comparable to these and should have
`a channel bit rate that is selectable with a suitable
`granularity so as to be efficiently less than or equal to
`the nominal information rates shown above.
`
`in meeting such requirements the DCSDS would
`support transmission of service multiplexes (which
`may include video) over existing circuits utilizing
`industry-standard
`switching
`and
`crosspoint
`equipment.
`
`3.9
`
`SONET/ATM compatibility
`
`provide
`services will
`telephony
`digital
`Future
`significant global data delivery mechanisms in the
`current and following decades.
`Some promising
`standards which are still in the process of becoming
`finalized and which have not yet received extensive
`service-carrier support are the Synchronous Optical
`Network
`transmission
`hierarchy
`(SONET)
`and
`Asynchronous Transfer Mode (ATM). These provide
`the physical. data and transport protocols (or the
`Broadband integrated Services Digital Network (8-
`ISBN)
`
`SONEI’ wm make available very large bandwidth
`(gigabit and above) data pipelines over the world's
`telephone system. Deployment of such networks is
`progressing very slowly, and even Narrowband-lSDN
`(N-lSDN) line access is currently only between 15%
`and 50% in the seven regional Bell companies in the
`U.S.
`
`Both SONET and ATM seem destined for widespread T
`
`Scientific-Atlanta
`
`6
`
`November 2. 1992
`
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`OpenTV Exhibit 1002 Page 6
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`

`
`ISOIIEC JTC1ISC2IWG1‘|. MPEG 92.]
`
`popularity, however. The ability to use SONEl' and to
`map the DCSDS multiplex approach into the
`asynchronous cell-relay format offered by ATM will
`give it a more universal relevance in global digital
`switched delivery environments in the latter part of this
`decade.
`
`ATM provides fixed-length 53 byte ‘cells’ which occur
`in the transmission channel on an lsochronous basis.
`Each cell
`is pre-pended with a 5-byte header that
`contains routing and channel—usage inforrnatlon. This
`yields a 48-byte payload. Thus, a connection-oriented
`service is possible in which a single point-to~point or
`point-to-muitl-point
`transfer
`is accomplished via
`explicit cell routing. ATM cells provide a high-speed
`switching mechanism (millions of cells per second)
`with low delay. in which video, volce,and data traffic
`can flow on a freely lntermbced demand-packet basis.
`For data. ATM can supply non-blocking transmission
`and a guaranteed bit-rate.
`In fact. ATM may see
`deployment in private U-AN environments before its
`general usage in wide-area networks.
`
`it should be noted that without some additional
`conditional access mechanism, ATM data streams
`would be liable to illegal reception and distri“bution.
`although the intended physical transmission medium
`('rl optical fiber) may make this more difficult than
`some other methods. The DCSDS should provide the
`additional security and signal protection.
`
`3.11
`
`Flexible re-allocation of bandwidth between
`services
`_
`-
`
`Depending on specific network features. the fixed
`bandwidth available in a transmission channel may
`demand reallocation amongst a changing array of
`services on daily. hourly or even more frequent
`intervals The control structures in the DCSDS should
`provide a mechanism for such reallocation.
`
`Some examples would include one hlgh—rate video
`being replaced by several videos of lower rate; audio
`channels being reassigned as data conduits; and an
`entire channel being designated to carry conditional
`access packets during certain hours.
`
`3.12
`
`Support for statistical multiplexing
`
`An even more dynamic form of data reallocation is
`required in the form of statistical multiplexing. This is
`the active sharing of the total channel video data rate
`amongst several Independent video bitstreams on a
`lrame-by-frame basis. Thus, video bit rate not used to
`encode a video with a scene of
`relatively lower
`complexity (and/or high temporal correlation to a
`previous scene) can be assigned in real-time to video
`streams which have scenes of higher complexity
`(and/or low intemai temporal correlation).
`
`3.10
`
`Scalability in service data rates
`
`3.13
`
`Scalable in overall channel data rates
`
`A practical digital services transmission system must
`support a large range of service rates: From HDTV
`signals at 16 to 18 Mbps to computer-oriented
`services at 9600 bps or less. Within a single service
`category, bit rates may also vary widely. Thus, a
`single system may need capabilities to accommodate
`the
`transmission
`of
`relatively
`low bit-rate
`(approximately 1 Mbps) movie-sourced material or
`studio-quaiityvideo signals at around 8 Mbps. These
`may need to be canied simultaneously or the channel
`bandwidth may need to be re-allocated overtime to
`a changing array ct services at varied bit rates.
`
`The control of such allocation and the flexflaiiity of
`data rates provided must be scalable so that service
`_allocations within a fixed channel rate may be simply
`and efficiently altered in a manner that may be
`handled by a uniiorrn encode/decode hardware
`implementation.
`
`The design of the DCSDS multiplex must be directly
`adjustable to handle total channel data rates over as
`wide
`a
`range as permitted by the ‘physical
`transmission media over which the signal is sent. The
`basic
`framing,
`synchronization.
`interleaving,
`cryptographic and other parameters required for
`transmission should be adaptively variable as overall
`bit rate increases or decreases.
`
`3.14 Uses simple and convenient clock/PLLs
`for service regeneration (NTSC, PAL,
`Secam, digital audio, etc.)
`
`In the most general multiplex. a mix of service types
`may be anticipated.
`The regeneration of such
`services into the analog domain will require that
`clocks. phased-locked loops (PLLs) and frequency
`dividers with parameters specific to the individual
`
`Scientific-Atlanta
`
`7
`
`November 2, 1992
`
`(cid:50)(cid:83)(cid:72)(cid:81)(cid:55)(cid:57)(cid:3)(cid:3)(cid:3)(cid:3)(cid:40)(cid:91)(cid:75)(cid:76)(cid:69)(cid:76)(cid:87)(cid:3)(cid:20)(cid:19)(cid:19)(cid:21)(cid:3)(cid:3)(cid:3)(cid:3)(cid:51)(cid:68)(cid:74)(cid:72)(cid:3)(cid:26)
`OpenTV Exhibit 1002 Page 7
`
`

`
`w-ilgwqki; Rnquiurlltttl and Method lorl-Iioh-Level Multiplexing of MPEG and Other Digital Service Bitatnuru With Univtrnl Transport Layer
`
`application domains be available in the decoder.
`Further. since it may be desired that several video (or
`other) services which are co-generated travel together
`in a gen-locked fashion, it would be favorable to use
`the data channel itself to derive the overall system
`clock.
`
`This being the case. manufacturing economics are
`best served by selecting a fundamental multiplex rate
`which can be used to derive all
`frequencies
`demanded by the application areas of interest.
`
`This basic clock should be simple to generate and
`provide for sufficient granularity in the establishment
`of overall channel and service data rates
`
`it is also advantageous if the clock is conveniently
`related to input sampling rates as well.
`
`3.15
`
`Robust and stable syncing in channels
`with high (1o'°) BER
`
`CATV error characteristics tend to be bursty and
`BEFis of 10" are quite common. Thus. Sufficlenl 9770'
`correction and a robust synchronization method is
`essential.
`
`Satellite applications, especially, will bring about the
`need for highly robust transmission signals.
`it can be
`assumed that for Ku Band channels. operation at 10
`error rates will be necessary.
`Since digital video
`signals degrade from excellem quality to total loss
`over a relatively narrow error regime (approximately 1
`dB) compared to analog transmission and because
`channel bit-error rates may be very unpredictable. the
`need for a strong syncing strategy is increased.
`
`the reliable
`Also. over any transmission channel.
`transport of system and conditional access data will
`be required even after some services have become
`unusable. Thiswouid support. lor instance. the stable
`delivery of entitlement. tuning and other data required
`for the staging and initialization of home terminals
`before their deployment at subscriber premises.
`it
`would also permit vital encryption key management
`information to arrive with greater certainty.
`
`To maintain continuity of these other data streams, a
`dependable synchronization method is fundamental.
`
`3.16
`
`system and
`of
`delivery
`Support:
`conditional access data In a predictable
`and suitably short period
`-
`
`Asymmetric cryptographic systems which rely on keys
`or seeds which are fbred over long periods of time.
`present attractive targets for signal piracy.
`To
`increase
`security and to ensure
`short
`signal
`acquisition times. these encryption parameters should
`be changed with frequencies oi approximately 5 to 10
`Hz. The DCSDS must accommodate these cycles by
`reliably providing for their transmission within the
`required tolerances
`
`3.17
`
`Allows simple de-muxing and re-muxing in
`the digital domain to support flexible re-
`routing of service packages
`
`Collections of services called ‘packages’, are content
`related bundles that are intended to be transported
`lndivlsibiy until their arrival at the final decode-and-
`display point. However. it may be desired that these
`bundles be freely combined with other bundles for
`transmission over a high bit rate channel to be later
`extracted for separate transmission over a lower bit
`rate channel. Similarly. because of common origin,
`several bundles of
`services may have to be
`transferred over a common channel (e.g.. satellite
`transponder) to be later unbundled and recombined
`with other bundles from difierent channels of like (or
`dilferent kind) into a secondary hop channel in a
`distribution network (e.g.. CATV channels).
`
`The method of framing or packetlzing in the DCSDS
`multiplex should support such de-routing and re-
`routing without requiring that complete de-mLrxing, de-
`erroring, decrypting or other processing-intensive
`activities
`(and their
`lnverses) be applied to the
`bltstrearn
`
`3.18
`
`hierarchical
`a
`Supports
`mechanism ('super1raming')
`
`transport
`
`It is desirable in a DCSDS to support a multiplexing
`strategy in which smaller content- or logically-related
`sub-lrames (‘bundles’) may be easily combined into
`larger structures that are handled unilormly by the
`transport hardware (as mentioned in the previous
`section).
`This concept can be described as
`'superframing'.
`It also intimately related to the re-
`routing strategies of the previous section
`
`Scientific-Atlanta
`
`3
`
`November 2. 1992
`
`(cid:50)(cid:83)(cid:72)(cid:81)(cid:55)(cid:57)(cid:3)(cid:3)(cid:3)(cid:3)(cid:40)(cid:91)(cid:75)(cid:76)(cid:69)(cid:76)(cid:87)(cid:3)(cid:20)(cid:19)(cid:19)(cid:21)(cid:3)(cid:3)(cid:3)(cid:3)(cid:51)(cid:68)(cid:74)(cid:72)(cid:3)(cid:27)
`OpenTV Exhibit 1002 Page 8
`
`

`
`ISOIIEC JTC1 ISCZIWG11. MPEG 92!
`
`Data structures in the DCSDS multiplex should furnish
`a wide range of superframing capability. This should
`include large or no limits on the number of subtrames
`t