1、 ETSI TS 103 464 V1.1.1 (2016-09) Hybrid Broadcast Broadband TV Application Discovery over Broadband TECHNICAL SPECIFICATION ETSI ETSI TS 103 464 V1.1.1 (2016-09)2 Reference DTS/JTC-039 Keywords broadcasting, DVB, HTML, internet ETSI 650 Route des Lucioles F-06921 Sophia Antipolis Cedex - FRANCE Tel
2、.: +33 4 92 94 42 00 Fax: +33 4 93 65 47 16 Siret N 348 623 562 00017 - NAF 742 C Association but non lucratif enregistre la Sous-Prfecture de Grasse (06) N 7803/88 Important notice The present document can be downloaded from: http:/www.etsi.org/standards-search The present document may be made avai
3、lable in electronic versions and/or in print. The content of any electronic and/or print versions of the present document shall not be modified without the prior written authorization of ETSI. In case of any existing or perceived difference in contents between such versions and/or in print, the only
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5、r ETSI documents is available at https:/portal.etsi.org/TB/ETSIDeliverableStatus.aspx If you find errors in the present document, please send your comment to one of the following services: https:/portal.etsi.org/People/CommiteeSupportStaff.aspx Copyright Notification No part may be reproduced or uti
6、lized in any form or by any means, electronic or mechanical, including photocopying and microfilm except as authorized by written permission of ETSI. The content of the PDF version shall not be modified without the written authorization of ETSI. The copyright and the foregoing restriction extend to
7、reproduction in all media. European Telecommunications Standards Institute 2016. European Broadcasting Union 2016. All rights reserved. DECTTM, PLUGTESTSTM, UMTSTMand the ETSI logo are Trade Marks of ETSI registered for the benefit of its Members. 3GPPTM and LTE are Trade Marks of ETSI registered fo
8、r the benefit of its Members and of the 3GPP Organizational Partners. GSM and the GSM logo are Trade Marks registered and owned by the GSM Association. HbbTV is a registered trademark of HbbTV Association. ETSI ETSI TS 103 464 V1.1.1 (2016-09)3 Contents Intellectual Property Rights 4g3Foreword . 4g3
9、Modal verbs terminology 4g3Introduction 4g31 Scope 6g32 References 6g32.1 Normative references . 6g32.2 Informative references 7g33 Definitions and abbreviations . 7g33.1 Definitions 7g33.2 Abbreviations . 7g34 Overview (informative) 7g35 HbbTVApplication Discovery over Broadband 8g35.1 Introduction
10、 8g35.2 Retrieving a Discovered AIT 9g35.3 Using a Discovered AIT . 9g35.4 Service Identification . 10g35.4.1 Service Identification in the presence of DVB Service Information . 10g35.5 HbbTVDNS FQDN Construction . 10g35.5.1 HbbTV DNS FQDN Construction in the presence of DVB Service Information . 10
11、g35.6 Resolution of Authoritative FQDN 10g35.7 Resolution of Service Record . 11g35.8 AIT retrieval . 11g35.8.1 AIT retrieval in the presence of DVB Service Information 11g35.9 Caching policy 12g35.10 XML AIT for Broadcast-related broadband application discovery 12g36 Other aspects (informative) 13g
12、3Annex A (informative): Change History 14g3History 15g3ETSI ETSI TS 103 464 V1.1.1 (2016-09)4 Intellectual Property Rights IPRs essential or potentially essential to the present document may have been declared to ETSI. The information pertaining to these essential IPRs, if any, is publicly available
13、 for ETSI members and non-members, and can be found in ETSI SR 000 314: “Intellectual Property Rights (IPRs); Essential, or potentially Essential, IPRs notified to ETSI in respect of ETSI standards“, which is available from the ETSI Secretariat. Latest updates are available on the ETSI Web server (h
14、ttps:/ipr.etsi.org/). Pursuant to the ETSI IPR Policy, no investigation, including IPR searches, has been carried out by ETSI. No guarantee can be given as to the existence of other IPRs not referenced in ETSI SR 000 314 (or the updates on the ETSI Web server) which are, or may be, or may become, es
15、sential to the present document. Foreword This Technical Specification (TS) has been produced by Joint Technical Committee (JTC) Broadcast of the European Broadcasting Union (EBU), Comit Europen de Normalisation ELECtrotechnique (CENELEC) and the European Telecommunications Standards Institute (ETSI
16、). NOTE: The EBU/ETSI JTC Broadcast was established in 1990 to co-ordinate the drafting of standards in the specific field of broadcasting and related fields. Since 1995 the JTC Broadcast became a tripartite body by including in the Memorandum of Understanding also CENELEC, which is responsible for
17、the standardization of radio and television receivers. The EBU is a professional association of broadcasting organizations whose work includes the co-ordination of its members activities in the technical, legal, programme-making and programme-exchange domains. The EBU has active members in about 60
18、countries in the European broadcasting area; its headquarters is in Geneva. European Broadcasting Union CH-1218 GRAND SACONNEX (Geneva) Switzerland Tel: +41 22 717 21 11 Fax: +41 22 717 24 81 Modal verbs terminology In the present document “shall“, “shall not“, “should“, “should not“, “may“, “need n
19、ot“, “will“, “will not“, “can“ and “cannot“ are to be interpreted as described in clause 3.2 of the ETSI Drafting Rules (Verbal forms for the expression of provisions). “must“ and “must not“ are NOT allowed in ETSI deliverables except when used in direct citation. Introduction The versions ETSI TS 1
20、02 796 1 published to date rely on signalling in the broadcast to start broadcast-related applications, through the Application Information Table (AIT). The present document defines a method for discovery of broadcast-related HbbTVservices via a broadband internet connection for settings where AIT s
21、ignalling via the broadcast network is not available to the HbbTVterminal. The discovery method relies on retrieving or extracting a unique identifier for a broadcast channel and then starting a discovery process to find a server that can be contacted to retrieve an AIT over the broadband connection
22、. The broadband-retrieved AIT would only be used if no AIT is available in the broadcast channel. The discovery process relies on the Internets DNS system. In simplified form, the process works as follows: Extract a unique identifier from the broadcast channel. (The present document specifies how to
23、 do this for a terminal that receives a DVB signal). With the unique identifier, perform a DNS query to find (resolve) the AIT server. Ask the AIT server for an AIT that matches the broadcast channel. ETSI ETSI TS 103 464 V1.1.1 (2016-09)5 Using the AIT, retrieve the HbbTV application. This AIT retr
24、ieved over the broadband connection and the Application referenced in that AIT are not necessarily the same as the AIT that would be available in the broadcast and the associated HbbTVApplication. Generally, when no AIT is available in the broadcast, then neither would be event signalling, and the p
25、rovider of the application may want to resort to alternative methods for providing event signalling to the HbbTVapplication - and the application may have to be modified to accommodate this. The discovery method does not allow for application changes over time - e.g. when the program changes. If thi
26、s behaviour is needed then the application will have to include the necessary logic. Entities relying on the functionality provided in the present document are advised to consider these limitations when writing their applications. The method accounts for privacy concerns, and has been designed in su
27、ch a way that no entity involved in the discovery process can learn the viewer behaviour of a user of a TV set equipped with this technology. This is the reason for the cache provisions in clause 5.7. ETSI ETSI TS 103 464 V1.1.1 (2016-09)6 1 Scope The present document augments clause 6 of ETSI TS 10
28、2 796 1, which states that broadcast-related applications are signalled as part of the broadcast. It defines a method for discovery of HbbTVapplications in settings where AIT signalling via the broadcast network is not available to the terminal. In this situation, an HbbTVterminal may discover broad
29、cast-related HbbTVservices via a broadband internet connection. 2 References 2.1 Normative references References are either specific (identified by date of publication and/or edition number or version number) or non-specific. For specific references, only the cited version applies. For non-specific
30、references, the latest version of the referenced document (including any amendments) applies. Referenced documents which are not found to be publicly available in the expected location might be found at https:/docbox.etsi.org/Reference. NOTE: While any hyperlinks included in this clause were valid a
31、t the time of publication, ETSI cannot guarantee their long term validity. The following referenced documents are necessary for the application of the present document. 1 ETSI TS 102 796: “Hybrid Broadcast Broadband TV“. NOTE 1: This document is also referred to as the Main HbbTVSpecification. NOTE
32、2: Including the latest errata as published on http:/hbbtv.org/resource-library/#specifications. 2 ETSI TS 102 796 (V1.4.1): “BROADCAST Hybrid Broadcast Broadband TV“. NOTE: Including the latest errata as published on http:/hbbtv.org/resource-library/#specifications. 3 ETSI EN 300 468: “Digital Vide
33、o Broadcasting (DVB); Specification for Service Information (SI) in DVB systems“. 4 Open IPTV Forum Release 2 specification, volume 5 (V2.3): “Declarative Application Environment“. 5 ETSI TS 102 034 (V1.5.1): “Digital Video Broadcasting (DVB); Transport of MPEG-2 TS Based DVB Services over IP Based
34、Networks“. 6 ETSI TS 102 809 (V1.2.1): “Digital Video Broadcasting (DVB); Signalling and carriage of interactive applications and services in Hybrid Broadcast/Broadband environments“. 7 IETF RFC 2782: “A DNS RR for specifying the location of services (DNS SRV)“. 8 W3C Recommendation (Second Edition)
35、 (10 June 2008): “XML Signature Syntax and Processing“. ETSI ETSI TS 103 464 V1.1.1 (2016-09)7 2.2 Informative references References are either specific (identified by date of publication and/or edition number or version number) or non-specific. For specific references, only the cited version applie
36、s. For non-specific references, the latest version of the referenced document (including any amendments) applies. NOTE: While any hyperlinks included in this clause were valid at the time of publication, ETSI cannot guarantee their long term validity. The following referenced documents are not neces
37、sary for the application of the present document but they assist the user with regard to a particular subject area. i.1 ETSI TS 103 270 (V1.1.1): “RadioDNS Hybrid Radio; Hybrid lookup for radio services“. 3 Definitions and abbreviations 3.1 Definitions For the purposes of the present document, the t
38、erms and definitions given in ETSI TS 102 796 1 and the following apply: AIT Server: server that for provides broadcast-related AIT(s) over broadband authoritative FQDN: internet domain for a (HbbTV) service provider discovered AIT: Broadcast related AIT retrieved according to the present document H
39、bbTVDNS FQDN: internet domain constructed only for the purpose of querying DNS 3.2 Abbreviations For the purposes of the present document, the abbreviations given in ETSI TS 102 796 1 apply. 4 Overview (informative) The methodology is modelled after RadioDNS i.1, using certain parameters provided in
40、 the broadcast for the identification of services. These could be digital parameters extracted from DVB Service Information, e.g. DVB-SI 3, or parameters encoded in a digital watermark that is inserted for the purpose of enabling this discovery method. The present document defines operation in the p
41、resence of DVB Service Information; other operation modes may be added in a future version. The discovery method allows broadcasters to uniquely associate an AIT server with their channel and comprises discovering an authoritative FQDN for a TV service, including discovery using DNS queries to hbbtv
42、dns.org, a root domain name server. Also defined is the methodology for discovery of an hbbtv-ait service record, which allows for construction of the (HTTPS) URL to retrieve an AIT from the broadcaster. NOTE: It is possible for local markets to define a market-specific alternative to hbbtvdns.org;
43、this is not further addressed in the present document. The protocol for discovery and retrieval of an AIT for a single service follows a number of steps, as outlined below. Figure 1 illustrates the steps using the example of DVB-based parameters. The terminal queries the root domain name server usin
44、g an HbbTVDNS FQDN constructed from information present in the broadcast (1). The root domain name server returns the authoritative FQDN for that service, if available (2). ETSI ETSI TS 103 464 V1.1.1 (2016-09)8 The terminal sends a DNS SRV query to the authoritative FQDN to locate the hbbtv-ait ser
45、vice, which can provide the AIT for the respective service (3). The authoritative FQDN returns the SRV record for the hbbtv-ait, if available (4). The terminal retrieves an XML-encoded AIT from the server using a URL constructed from the DNS SRV record as provided by the authoritative FQDN (5 and 6)
46、. When a broadcast service is selected from a service provider (broadcaster) that supports Application Discovery over Broadband, the terminal uses the AIT for that broadcast service and retrieves the application (7 and 8) if and when it cannot obtain an AIT from the broadcast signal. Figure 1: HbbTV
47、Application Discovery over Broadband in the presence of DVB Service Information This mechanism has been designed to protect the privacy of the end user; it does not reveal information about user viewing behaviour to third parties involved in the discovery process. The DNS server may gain knowledge a
48、bout (DVB) services that are available to a certain terminal but not which services are actually used. Further, the protocol is designed to let the terminal load AIT server URLs and AITs in its cache, so that it will not perform DNS queries or retrieve an AIT upon channel changes. The information th
49、at is potentially disclosed to channel providers (broadcasters) on using a Discovered AIT is comparable to what is disclosed when using an AIT signalled in the broadcast. 5 HbbTVApplication Discovery over Broadband 5.1 Introduction This clause defines a method for discovery and signalling of broadcast-related applications, which are discovered and signalled via broadband, instead of being signalled as part of the broadcast channel as defined in clause 7.2.3.1 of ETSI TS 102 796 1. ETSI ETSI TS 103 464 V1.
