INTERNATIONAL TELECOMMUNICATION UNION Document 23 – E
TELECOMMUNICATION
STANDARDIZATION SECTOR
TSB DIRECTOR’S CONSULTATION
MEETING ON IPTV STANDARDIZATION
Geneva, 4-5 April 2006
DOCUMENT 23
Source: TTA, ETRI, KT, Samsung Electronics, ICU, Kyunghee Univ., Yonsei Univ., HUFS
Title: Low Level Requirements on IPTV Global Standardization
Introduction
This contribution describes low level view of IPTV related technical requirements which could be developed
during the ITU-T IPTV standards activity to support globalize IPTV services.
1. Requirements for protection and governance of IPTV contents
Protection and governance to the contents that are delivered over the IP networks are essential pieces that
may enhance the attractiveness of IPTV based business. However, there are many protection algorithms and
mechanisms that IPTV vendors can apply. Hence, an interoperable way to protect IPTV contents is essential.
This section covers some requirements to support interoperability in secured and governed IPTV
applications.
1.1 General Requirements
IPTV’s protection mechanism is required to be flexible and extensible: Security is an active area
where algorithm / mechanism has relatively short lifetime due to the invention of novel attacks and
breaking methods. It is strongly recommended that the protection for the IPTV could be easily
extensible.
IPTV’s protection mechanism could support granular protection: It could be able to protect the
whole part or just some parts of the IPTV’s content.
IPTV’s protection mechanism could leave enough room for unique implementation by the vendors:
It could be able to describe the protection in a standard way. Through the standard description,
vendors can have their own implementation while still conformance to the described protection
mechanism.
IPTV’s protection mechanism could be able to fully exploit the strong point network capability
offered by the nature of IPTV technology. It could have a mechanism to be possible to download
the missing protection implementation (tool) that has been described by the protection description.
IPTV could have a model to specify the governance to the content: The governance helps the IPTV
terminal to determine whether content may be unprotect and consumed. Together with protection
mechanism, the governance will provide a complete authorized content consumption.
The governance could support common business models that are applied to the IPTV content (i.e.,
subscription model, pay per view model, etc).
IPTV could leverage the existing protection and governance specifications to avoid ‘re-inventing
the wheel.’
Contact: Ilyoung Chong Tel: +82-31-330-4229
TTA (HUFS) Fax: +82-31-339-5687
KOREA Email: iychong@hufs.ac.kr
Attention: This is not a publication made available to the public, but an internal ITU-T Document intended only for use by the
Member States of ITU, by ITU-T Sector Members and Associates, and their respective staff and collaborators in their ITU related
work. It shall not be made available to, and used by, any other persons or entities without the prior written consent of ITU-T.
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1.2 Specific Requirements
The adopted protection description could be represented in XML metadata (whether in text-based
instance or binary instance).
It should be also possible to protect the protection metadata itself (hierarchical protection).
Metadata is also considered as a valuable item that one wants to protect.
The IPTV multicasting with metadata only shall be possible.
The multicasting with metadata in conjunction with the audiovisual contents of the IPTV programs
shall be possible.
The protection of the privacy information in the metadata shall be possible.
2. Requirements for Quality monitoring of IPTV Services
IPTV will open many new applications in multimedia service market with increased flexibility and
diversity. As multimedia contents are transmitted over IP networks, multimedia data can be delayed or lost,
resulting in degraded quality of audio and video signals. Furthermore, the impairment level depends on the
status and congestion of the network. Meanwhile, some commercial IPTV services require acceptable
video/audio quality. Therefore, it would be requested that the IPTV standards could address the following
quality issues:
Methods to monitor the video quality of the receiver with a minimum use of additional bandwidth.
Real-time monitoring methods for the video quality of the receiver.
Methods to monitor the audio quality of the receiver with a minimum use of additional bandwidth.
Real-time monitoring methods for the audio quality of the receiver.
Furthermore, it would be desirable to use standardized monitoring method according to video/audio
quality metrics. In this regard, efforts are made in ITU-T SG9 to produce standards for objective multimedia
video and audio quality measurement.
3. Requirements for DBM and Enhanced EPG
This section explains requirements for the DBM (Data Broadcast Middleware) to receive and execute
various IPTV services including real-time broadcast services like VOD, PPV and the enhanced EPG to
support an easy search and selection of the IPTV service.
3.1 Requirements for the Data Broadcast Middleware (DBM)
Currently available terrestrial/satellite/cable services apply their different middleware functions to provide
their unique services. And in order to support the conversational broadcast services the Java based
applications demanding the high-quality AV information will be required. Therefore, the DBM should
provide a function to abstract and operate an application from the received Data Broadcast Streams
throughout the IP Tuner in order to accommodate the DBS in IPTV.
There are needs for standardization on the utilization method of various broadcast contents in order to
provide interoperability among existing broadcast middleware.
Requirement: The IPTV DBM could provide a framework to receive and process the Data Broadcast
Services.
Receiving Function for the Data Broadcast Streams: It processes an analysis and management of
the service information from the received real-time data broadcast via the broadband network.
Signalling Function for the Data Broadcast Application: It provides a packaging of the
application related information that is abstracted from the broadcast data stream as well as supports
execution environments of the applications.
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DBM API: It provides a standard API for the Data Broadcast Applications to access various
functions of the DBM.
3.2 Requirements for the Enhanced EPG (Electronic Program Guide)
The IPTV will provide an interactive services to search and select of information according to ISP
application features. However, the currently available EPG information is only applicable to the real-time
broadcast service and provided with search and selection of the service information like VoD and PPV.
Therefore, the enhanced EPG is required to provide efficient management and provision of the integrated
channel information on broadcast services, VoD, PPV and offline media in the IPTV service.
Requirement: A framework could be provided for the real-time data broadcast, VoD, PPV and other
streaming service including the offline media with its applications.
Definition of the IPTV Service Expression Schema: It requires a definition of a schema for the
integrated EPG from the information of various services in the IPTV.
IPTV Service Information Transport Protocol: The transport protocol for the information delivery
of the Enhanced EPG between client and server is required.
IPTV Service Search and Selection: An enhanced function for a service discovery and selection of
the IPTV will be implemented through enhanced EPG as well as an integration function with the
IPTV Middleware well.
4. Requirements on Metadata for IPTV Services
With advance of the communication networks, rich media services have become possible over the IP
based networks. In the past, the traditional broadcasting networks are the only means to deliver to the
consumers the rich media such as video contents with SD- or HD-level quality. However, the IP based
networks are now becoming more competitive in terms of delivery bandwidth and interactivity to the
contents. Furthermore, the amount of multimedia contents is ever increasing and many of them can be
available over the IP based network to the consumer devices such as IP-STB.
The current IPTV services are focused on delivery of the audiovisual contents. In order to easily find,
navigate and browse the IPTV contents that users are interested, metadata service is essential in conjunction
with the provision of the audiovisual contents. And it is strongly necessary to standardize a mean for
searching the contents on various IPTV services. Therefore, the metadata for the IPTV can provide rich
information about the program contents such as program title, genre, synopsis, actors/actresses, copyright
information, production date, emission date etc. From the metadata with the essential information, intelligent
filtering and searching applications are also possible in IPTV service frameworks. Even in the traditional
broadcasting services, some simple metadata are already explored in the form of EPG.
4.1 General Requirements
IPTV Metadata Provision: Metadata shall be provided in conjunction with the audiovisual contents
of the IPTV program.
IPTV Metadata Consumption: The IPTV Metadata consumption shall be possible on the IPTV
terminals such that easy access to specific IPTV programs could be possible and associated
information is easily acquired.
It is necessary to consider the existing and matured standards on metadata for TV programs to be
adopted for IPTV applications by avoiding the reinvention of a new metadata.
The metadata shall be flexible and extensible for the future advanced IPTV services, and be
interoperable as much as possible with the metadata in traditional broadcasting services.
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4.2 Specific Requirements
The IPTV metadata shall be effectively represented in XML Schema.
The interaction to IPTV metadata shall be possible.
The metadata multicasting in conjunction with the audiovisual contents of the IPTV programs shall
be possible.
The metadata multicasting without the audiovisual contents of the IPTV programs shall be possible.
The protection of the metadata shall be possible.
The protection of the privacy information in the metadata shall be possible.
5. Requirements of IPTV Coding
This section explains technical requirements of video coding and describes scalable video coding as the
main video codec in the Global IPTV service. The SVC suits best to time-varying un-guaranteed
transmission channels such as IP networks.
5.1 History of video codec
ITU-T and MPEG have been standardizing video codecs. ITU-T standardized H.26x series such as H.261
and H.263, while MPEG standardized MPEG-1, MPEG-2, and MPEG-4 video codecs. Coding algorithms of
two organizations are similar. But, their goals were different. H.26x series were developed for video
telephony while MPEG series were developed mainly for broadcasting of high quality video. Since early
2000s, they got together and in 2004 developed H.264/AVC which is MPEG-4 Part 10. It is believed the
most efficient video codec.
.
Figure 1 History and Trend of Video Coding
5.2 Proposal for requirements on video coding scheme
In order for video service to be adaptable to time-varying condition of terminal capability, network
capability, and user preference, the following requirements are recommended.
Spatial resolution could be ranged from PDA size to HDTV size.
Temporal resolution could be ranged from 7.5 frames per sec to 60 frames per sec.
Quality levels could be selectable among more than 3 levels.
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Parameters for video traffic could be compatible to traffic parameters used in the Internet standard
e.g. RSVP.
Video coding scheme could be equipped with packet loss resilience tools.
Video coding scheme could include low delay mode (e.g. less than 50ms delay caused by the video
decoder).
SVC based IPTV could be capable of layered multicast scheme.
The metadata information for a tuned channel could contain a mapping between the content channel
and the corresponding multicast addresses which belong to that content channel.
Complexity of video adaptation to heterogeneous conditions could be as low as possible because
adaptation is often performed in intermediate network device (proxy, gateway, router, etc.) to react
to time varying constraints in real-time.
This flexibility in video adaptations can provide more appropriate solutions to meet various kinds of
constraints of transmission and consumption resource.
Third, it is also important to find systematic solutions in choosing the optimal adaptation operation
among multiple options in spatial, temporal, SNR, and their combinations for given constraints. At
the same time, video adaptation should be performed in an interoperable way to be deployed across
heterogeneous service environments.
DSCP Field designation for QoS classes: There are standardization activities to assign DSCP field
for video services over IP (e.g. DVB-IP ETSI TS 102 034) and it could be further investigated if
additional mapping for SVC layering is required or not.
Policy of session assignment to SVC layers : Each layer of SVC-encoded contents can be streamed
1) by a single UDP session that contains whole layers or 2) by multiple UDP sessions each of which
contains the corresponding layer. The former can save overhead but the latter has flexibility when
implementing tools such as UEP(unequal error protection). Pros and cons of each method should be
investigated.
QoS parameter report : In a heterogeneous network, overall transmission capability can be
constrained by some intermediate network hops (e.g. wireless LAN or cellular network). In order to
support best adaptation, the information of the network condition of these particular hops should be
informed accurately and promptly. These constrained hops should have an ability to inform its
information of the channel status (e.g. bandwidth, packet and/or frame error rate and occurrence of
handoff) to its terminal when it is requested.
6. Requirements for the Content Security (DRM/CAS)
It is considered as principal requirement to implement the content security for the copyright protection of
the interactive IPTV contents. The two content security approaches, CAS (Conditional Access System) for
the customized broadcast services and DRM (Digital Rights Management) for the Internet services, are
necessary to provide an integrated content security in emerging ubiquitous environments and digital
convergence. For that reason the three major requirements on IPTV content security are as follows.
Requirement 1: The IPTV service could provide a copyright protection of the broadcasting contents and
apply the content security in order to support various business models.
Content Protection : It provides the fundamental protection of the IPTV content which includes
real-time cryptography, high speed key generation algorithm, key distribution and
watermarking/fingerprinting methods.
Access Control : It provides an access control of users to protect the IPTV content including
subscriber authentication & management, content packaging, license issuing/management,
IPMP(Intellectual Property Management and Protection) interface, rights enforcement technology.
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Rights Expression : It represents rights of the content with XML(eXtensible Mark-up Language) to
provide interoperability. The XrML (eXtensible Rights Mark-up Language) or ODRL(Open Digital
Rights Language) is implemented internationally.
Domain Management : It provides a efficient management of the content when a single user control
multiple devices with support of following technologies; device certification, virtual domain
configuration, domain join & leave, rights information delivery and enforcement within the domain
technology.
Requirement 2: The content security for the copyright protection of the IPTV content could operate within
the trusted security domain.
The IPTV content security needs to provide the operation of the copyright protection within the
trusted environment since it is possibly expected security attacks from adversary devices.
Requirement 3: The content security for the copyright protection of the IPTV content should provide
interoperability without technological dependency.
Mismatches will be possibly occurred among various vendors which adopts different content
security which is dependent on a particular technology. Thus, a framework of the content security
should be designed to provide their interoperability well.
7. Conclusion
This contribution shows various requirements which could be developed during the ITU-T IPTV standard
activities. To accelerate development, it is highly requested working together with other related SDOs
(Standard Development Organizations) subject by subject. And it also proposed to transfer these
requirements as initial input for ITU-T IPTV group for their further development.
8. Contributors
Tel: 82-42-860-5181
Eui Hyun PAIK ETRI, KOREA Email: ehpaik@etri.re.kr
Fax: 82-42-860-5218
Tel: 82-42-860-6851
Hye Kyeong PARK ETRI, KOREA Email: phk@etri.re.kr
Fax: 82-42-860-5218
Tel: 82-42-860-6615
HeeKyung Lee ETRI, KOREA Email: lhk95@etri.re.kr
Fax: 82-42-860-5479
Tel: 82-42-860-6384
Bong Jin OH ETRI, KOREA Email: bjoh@etri.re.kr
Fax: 82-42-860-5218
Tel: 82-42-866-6137
Munchurl Kim ICU, KOREA Email: mkim@icu.ac.kr
Fax: 82-42-866-6245
Yonsei University, Tel: 82-2-2123-2779
Chulhee Lee Email: chulhee@yonsei.ac.kr
KOREA Fax: 82-2-312-4584
Tel: 82-2-526-6529
Lark Kwon Choi KT, KOREA Email: biorock@kt.co.kr
Fax: 82-2-526-5909
Tel: 82-2-526-6578
Sang Soo Lee KT, KOREA Email: ssllee@kt.co.kr
Fax: 82-2-526-5909
Tel: 82-2-526-6580
Dae-Gun Kim KT, KOREA Email: dkim@kt.co.kr
Fax: 82-2-526-5909
Tel: 82-31-201-2586
Doug Young SUH Kyunghee Univ., KOREA Email: suh@khu.ac.kr
Fax: 82-31-203-1494
Samsung Electronics,
Seok Ha KOH Email: seok.koh@samsung.com
KOREA
Tel: 82-42-860-5353
Seong-Jun Bae ETRI, KOREA Email: sjbae@etri.re.kr
Fax: 82-42-860-5479
Tel: 82-42-860-5137
Jung Won Kang ETRI, KOREA Email: jungwon@etri.re.kr
Fax: 82-42-860-5479
Chaesup Lee ETRI, KOREA Email : genevalee@empal.com Tel: 41-76-411-4871
Tel: 82-31-330-4229
Ilyoung Chong HUFS, KOREA Email: iychong@hufs.ac.kr
Fax: 82-31-339-5687
Tel: 82-42-860-6048
Jin Ho Hahm ETRI, KOREA Email: jhhahm@etri.re.kr
Fax: 82-42-860-5039
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