1、 International Telecommunication Union ITU-T Y.2235TELECOMMUNICATION STANDARDIZATION SECTOR OF ITU (11/2008) SERIES Y: GLOBAL INFORMATION INFRASTRUCTURE, INTERNET PROTOCOL ASPECTS AND NEXT-GENERATION NETWORKS Next Generation Networks Service aspects: Service capabilities and service architecture Con
2、verged web-browsing service scenarios in NGN Recommendation ITU-T Y.2235 ITU-T Y-SERIES RECOMMENDATIONS GLOBAL INFORMATION INFRASTRUCTURE, INTERNET PROTOCOL ASPECTS AND NEXT-GENERATION NETWORKS GLOBAL INFORMATION INFRASTRUCTURE General Y.100Y.199 Services, applications and middleware Y.200Y.299 Netw
3、ork aspects Y.300Y.399 Interfaces and protocols Y.400Y.499 Numbering, addressing and naming Y.500Y.599 Operation, administration and maintenance Y.600Y.699 Security Y.700Y.799 Performances Y.800Y.899 INTERNET PROTOCOL ASPECTS General Y.1000Y.1099 Services and applications Y.1100Y.1199 Architecture,
4、access, network capabilities and resource management Y.1200Y.1299 Transport Y.1300Y.1399 Interworking Y.1400Y.1499 Quality of service and network performance Y.1500Y.1599 Signalling Y.1600Y.1699 Operation, administration and maintenance Y.1700Y.1799 Charging Y.1800Y.1899 NEXT GENERATION NETWORKS Fra
5、meworks and functional architecture models Y.2000Y.2099 Quality of Service and performance Y.2100Y.2199 Service aspects: Service capabilities and service architecture Y.2200Y.2249 Service aspects: Interoperability of services and networks in NGN Y.2250Y.2299 Numbering, naming and addressing Y.2300Y.
6、2399 Network management Y.2400Y.2499 Network control architectures and protocols Y.2500Y.2599 Security Y.2700Y.2799 Generalized mobility Y.2800Y.2899 For further details, please refer to the list of ITU-T Recommendations. Rec. ITU-T Y.2235 (11/2008) i Recommendation ITU-T Y.2235 Converged web-browsi
7、ng service scenarios in NGN Summary Recommendation ITU-T Y.2235 describes converged web-browsing (CWB) capabilities for NGN. CWB capabilities are based on web-based application support built on NGN release 1 (see Recommendation ITU-T Y.2201), with the aim to provide users with a consistent web envir
8、onment which spans multiple network environments and multiple devices (PC, laptop, PDA, cell phone, etc.). CWB provides advanced web-browsing capabilities in different NGN devices and various network environments, including profile-based content adaptation capabilities. The CWB capabilities enable c
9、lient device (e.g., web browser) of NGN to browse web content effectively, regardless of device and network types. This Recommendation identifies web-browsing capability requirements, provides a functional model and service scenarios making use of converged web-browsing capabilities. Source Recommen
10、dation ITU-T Y.2235 was approved on 13 November 2008 by ITU-T Study Group 13 (2009-2012) under Recommendation ITU-T A.8 procedure. Keywords Converged web-browsing (CWB), NGN, web-browsing. ii Rec. ITU-T Y.2235 (11/2008) FOREWORD The International Telecommunication Union (ITU) is the United Nations s
11、pecialized agency in the field of telecommunications, information and communication technologies (ICTs). The ITU Telecommunication Standardization Sector (ITU-T) is a permanent organ of ITU. ITU-T is responsible for studying technical, operating and tariff questions and issuing Recommendations on th
12、em with a view to standardizing telecommunications on a worldwide basis. The World Telecommunication Standardization Assembly (WTSA), which meets every four years, establishes the topics for study by the ITU-T study groups which, in turn, produce Recommendations on these topics. The approval of ITU-
13、T Recommendations is covered by the procedure laid down in WTSA Resolution 1. In some areas of information technology which fall within ITU-Ts purview, the necessary standards are prepared on a collaborative basis with ISO and IEC. NOTE In this Recommendation, the expression “Administration“ is used
14、 for conciseness to indicate both a telecommunication administration and a recognized operating agency. Compliance with this Recommendation is voluntary. However, the Recommendation may contain certain mandatory provisions (to ensure e.g., interoperability or applicability) and compliance with the R
15、ecommendation is achieved when all of these mandatory provisions are met. The words “shall“ or some other obligatory language such as “must“ and the negative equivalents are used to express requirements. The use of such words does not suggest that compliance with the Recommendation is required of an
16、y party. INTELLECTUAL PROPERTY RIGHTS ITU draws attention to the possibility that the practice or implementation of this Recommendation may involve the use of a claimed Intellectual Property Right. ITU takes no position concerning the evidence, validity or applicability of claimed Intellectual Prope
17、rty Rights, whether asserted by ITU members or others outside of the Recommendation development process. As of the date of approval of this Recommendation, ITU had not received notice of intellectual property, protected by patents, which may be required to implement this Recommendation. However, imp
18、lementers are cautioned that this may not represent the latest information and are therefore strongly urged to consult the TSB patent database at http:/www.itu.int/ITU-T/ipr/. ITU 2009 All rights reserved. No part of this publication may be reproduced, by any means whatsoever, without the prior writ
19、ten permission of ITU. Rec. ITU-T Y.2235 (11/2008) iii CONTENTS Page 1 Scope 1 2 References. 1 3 Definitions 1 3.1 Terms defined elsewhere 1 3.2 Terms defined in this Recommendation. 2 4 Abbreviations 2 5 Conventions 3 6 Requirements for converged web-browsing capabilities 3 7 Functional model for c
20、onverged web-browsing. 3 7.1 Functional components. 4 7.2 Operation 6 8 Service scenarios using converged web-browsing capabilities in NGN 7 8.1 Basic scenario: Web-browsing capabilities without content adaptation 7 8.2 Extended scenario: Web-browsing capabilities with content adaptation. 8 9 Securi
21、ty consideration 10 Appendix I 11 I.1 CWB positioning within the NGN architecture. 11 I.2 Relationship between the web proxy function and NGN functional entities. 11 Bibliography. 14 iv Rec. ITU-T Y.2235 (11/2008) Introduction In NGN environments, web-based applications allow enhanced utilization of
22、 device capabilities and network characteristics ITU-T Y.2201. Web-browsing is one of the most popular web-based applications, and it is likely to be widely used in NGN environments. In NGN environments, however, traditional web-browsing capabilities may indeed cause failure of a users device, due t
23、o different types of devices (e.g., different screen size or resolution, etc.) and networks (e.g., roaming to different access network: CDMA, WLAN, WiMAX, Bluetooth, etc.). To support the web-browsing capabilities in NGN environments, it is required to provide profile based web-browsing capabilities
24、 with content adaptation. Converged web-browsing (CWB) capabilities enhance the web-browsing experience in terms of supporting different devices (e.g., mobile phone, smart phone, ultra mobile PC, laptop, etc.) and various access networks in NGN. Rec. ITU-T Y.2235 (11/2008) 1 Recommendation ITU-T Y.2
25、235 Converged web-browsing service scenarios in NGN 1 Scope The objective of this Recommendation is to describe converged web-browsing capabilities that transform the content according to the different device types of NGN terminals and various network environments supporting web-browsing capabilitie
26、s. The web-browsing model and service scenarios, using such converged web-browsing capabilities, are also given. The scope of this Recommendation is targeted at the converged web-browsing capabilities in NGN with its model and service scenarios. This Recommendation covers: Requirements to support co
27、nverged web-browsing capabilities; Converged web-browsing functional model; Converged web-browsing service scenarios. 2 References The following ITU-T Recommendations and other references contain provisions which, through reference in this text, constitute provisions of this Recommendation. At the t
28、ime of publication, the editions indicated were valid. All Recommendations and other references are subject to revision; users of this Recommendation are therefore encouraged to investigate the possibility of applying the most recent edition of the Recommendations and other references listed below.
29、A list of the currently valid ITU-T Recommendations is regularly published. The reference to a document within this Recommendation does not give it, as a stand-alone document, the status of a Recommendation. ITU-T Y.2012 Recommendation ITU-T Y.2012 (2006), Functional requirements and architecture of
30、 the NGN release 1. ITU-T Y.2201 Recommendation ITU-T Y.2201 (2007), NGN release 1 requirements. ITU-T Y.2701 Recommendation ITU-T Y.2701 (2007), Security requirements for NGN release 1. 3 Definitions 3.1 Terms defined elsewhere This Recommendation uses the following terms defined elsewhere: 3.1.1 c
31、ontent transformation function: A function that has capabilities to perform restructuring, recording and optimizing content. b-W3C CTG 1.0. NOTE Content transformation function is used for providing content adaptation capabilities in this Recommendation. 3.1.2 proxy: A software that receives HTTP re
32、quests and forwards that request toward an origin server (possibly by way of an upstream proxy) using HTTP. A proxy receives the response from the origin server and forwards it to the requesting client. b-W3C CC/PP structure and Vocabularies 2.0. 3.1.3 user agent: A client within a device that perfo
33、rms rendering. Browsers are examples of user agents. b-W3C GTDI. 2 Rec. ITU-T Y.2235 (11/2008) 3.2 Terms defined in this Recommendation This Recommendation defines the following terms: 3.2.1 content adaptation: Content adaptation is an action of transforming the content to adapt to device capabiliti
34、es and is done by content transformation function as well as profile serving function. NOTE For example, content adaptation can be applied to mobile devices that require special handling because of their limited computational power, small screen size and constrained keyboard functionality, etc. 3.2.
35、2 converged web-browsing capabilities: Web browsing capabilities that dynamically adapt web content to various terminal devices and network according to profile information, by using content adaptation in the NGN environment. 3.2.3 dynamic profile attribute: A profile attribute that may change its v
36、alue, e.g., as a result of hardware, software or configuration changes. Examples are the changing of location, battery life, network status (e.g., roaming) and user-defined screen size, etc. NOTE Dynamic profile attribute is not limited to the specific attribute. In other words, any kind of attribut
37、e could be a dynamic profile attribute. 3.2.4 static profile attribute: A profile attribute for a device that does not change its value. Examples are supported media types and protocols, screen details (size in pixels, colour resolution, response time, etc.) ITU-T Y.2201. In most cases, the static p
38、rofile attribute is stored in the profile server. 3.2.5 web browsing function: A software application which enables a user to display and interact with text, images, videos, music and other information typically located on a web page at a website on the world wide web or a local area network. 3.2.6
39、web content: A web content is the textual, visual or aural content that is encountered as part of the user experiences on websites. It may include, among other things: text, images, sounds, videos and animations. 3.2.7 web proxy function: An intermediary function between a web browsing function and
40、a web serving function, which performs protocol conversion, encoding/decoding/caching of content and brokering the HTTP requests (inserting or modifying the profile information into the HTTP request message) on behalf of the web browsing function. NOTE The most common use of a web proxy function is
41、to serve as a web cache. In this Recommendation, the meaning of web proxy function is extended. 3.2.8 web serving function: A function that is responsible for accepting HTTP requests from a web browsing function and serving them HTTP responses along with optional data content, which usually are web
42、pages such as HTML documents and linked objects (images, etc.). 4 Abbreviations This Recommendation uses the following abbreviations and acronyms: CDMA Code Division Multiple Access CWB Converged Web-Browsing GSC-FE General Services Control Functional Entity HTML HyperText Markup Language HTTP Hyper
43、Text Transfer Protocol MRC-FE Media Resource Control Functional Entity MRP-FE Media Resource Processing Functional Entity Rec. ITU-T Y.2235 (11/2008) 3 NGN Next Generation Network PDA Personal Digital Assistant SUP-FE Service User Profile Functional Entity TUP-FE Transport User Profile Functional En
44、tity URI Uniform Resource Identifier W3C World Wide Web Consortium WiMAX Worldwide Interoperability for Microwave Access WLAN Wireless Local Area Network 5 Conventions None. 6 Requirements for converged web-browsing capabilities This clause describes the requirements of converged web-browsing capabi
45、lities for NGN. The converged web-browsing capabilities are required to: Provide web-based application support satisfying with interoperability across wired and wireless network environment ITU-T Y.2201 Provide the profile serving function which stores the user profile and device profile information
46、 Provide profile processing to support content adaptation: Request and respond with the profile information to the profile serving function Update the profile information Adapt the profile information (inserting and modifying the profile) Provide content processing to support content transformation:
47、 Transform the content according to profile information Deliver the transformed content to requester (e.g., web proxy function) Provide the delivering of profile information by terminal: Send the profile information through HTTP request messages by the web browsing function (e.g., when the profile a
48、ttribute is changed) Provide the service registration function for the terminal: Registration and de-registration of the web browsing function to the web proxy function 7 Functional model for converged web-browsing This clause describes the functional model for CWB capabilities in NGN, including the
49、 functional components and operations. The roles of service components are specified in terms of profile delivery as well as content adaptation. Figure 1 shows the functional model for CWB capabilities. This model consists of five components: a web browsing function, a web proxy function, a web serving function, a profile serving function and a content transformation function. 4 Rec. ITU-T Y.2235 (11/2008) Figure 1 Functional model for converged web-browsing capabilities In CWB model, four kinds of b
