1、 International Telecommunication Union ITU-T Y.3045TELECOMMUNICATION STANDARDIZATION SECTOR OF ITU (01/2014) SERIES Y: GLOBAL INFORMATION INFRASTRUCTURE, INTERNET PROTOCOL ASPECTS AND NEXT-GENERATION NETWORKS Future networks Smart ubiquitous networks Functional architecture of content delivery Recom
2、mendation ITU-T Y.3045 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 Network aspects Y.300Y.399 Interfaces and protocols Y.
3、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, access, network capabilities and resource manageme
4、nt 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 IPTV over NGN Y.1900Y.1999 NEXT GENERATION NETWORKS Frameworks and functional
5、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 Enhancements to NGN Y.2300Y.2399 Network management Y.2400Y.2499
6、 Network control architectures and protocols Y.2500Y.2599 Packet-based Networks Y.2600Y.2699 Security Y.2700Y.2799 Generalized mobility Y.2800Y.2899 Carrier grade open environment Y.2900Y.2999 FUTURE NETWORKS Y.3000Y.3499CLOUD COMPUTING Y.3500Y.3999 For further details, please refer to the list of I
7、TU-T Recommendations. Rec. ITU-T Y.3045 (01/2014) i Recommendation ITU-T Y.3045 Smart ubiquitous networks Functional architecture of content delivery Summary Recommendation ITU-T Y.3045 specifies the functional architecture of content delivery in smart ubiquitous networks (SUN) by describing the rel
8、evant capabilities, functions, operations and informational flows. The features of SUN content delivery are name-based content routing, in-network content caching, content delivery optimization, and dynamic content routing adaptive to context information whose principles are content awareness and co
9、ntext awareness as defined in Recommendations ITU-T Y.3044 and ITU-T Y.3043, respectively. The content delivery in SUN consists of content publication, content service provisioning, content routing and content caching as capabilities to support the aforementioned features. History Edition Recommenda
10、tion Approval Study Group Unique ID*1.0 ITU-T Y.3045 2014-01-13 13 11.1002/1000/12077-en Keywords Content delivery, SUN. _ *To access the Recommendation, type the URL http:/handle.itu.int/ in the address field of your web browser, followed by the Recommendations unique ID. For example, http:/handle.
11、itu.int/11.1002/1000/11830-en. ii Rec. ITU-T Y.3045 (01/2014) FOREWORD The International Telecommunication Union (ITU) is the United Nations specialized agency in the field of telecommunications, information and communication technologies (ICTs). The ITU Telecommunication Standardization Sector (ITU
12、-T) is a permanent organ of ITU. ITU-T is responsible for studying technical, operating and tariff questions and issuing Recommendations on them with a view to standardizing telecommunications on a worldwide basis. The World Telecommunication Standardization Assembly (WTSA), which meets every four y
13、ears, establishes the topics for study by the ITU-T study groups which, in turn, produce Recommendations on these topics. The approval of ITU-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 ne
14、cessary standards are prepared on a collaborative basis with ISO and IEC. NOTE In this Recommendation, the expression “Administration“ is used for conciseness to indicate both a telecommunication administration and a recognized operating agency. Compliance with this Recommendation is voluntary. Howe
15、ver, the Recommendation may contain certain mandatory provisions (to ensure, e.g., interoperability or applicability) and compliance with the Recommendation is achieved when all of these mandatory provisions are met. The words “shall“ or some other obligatory language such as “must“ and the negative
16、 equivalents are used to express requirements. The use of such words does not suggest that compliance with the Recommendation is required of any party. INTELLECTUAL PROPERTY RIGHTS ITU draws attention to the possibility that the practice or implementation of this Recommendation may involve the use o
17、f a claimed Intellectual Property Right. ITU takes no position concerning the evidence, validity or applicability of claimed Intellectual Property Rights, whether asserted by ITU members or others outside of the Recommendation development process. As of the date of approval of this Recommendation, I
18、TU had received notice of intellectual property, protected by patents, which may be required to implement this Recommendation. However, implementers 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.i
19、nt/ITU-T/ipr/. ITU 2014 All rights reserved. No part of this publication may be reproduced, by any means whatsoever, without the prior written permission of ITU. Rec. ITU-T Y.3045 (01/2014) iii Table of Contents Page 1 Scope 1 2 References. 1 3 Definitions 1 3.1 Terms defined elsewhere 1 3.2 Terms d
20、efined in this Recommendation . 2 4 Abbreviations and acronyms 2 5 Conventions 2 6 Overview 2 7 Features and capabilities for SUN content delivery . 3 8 Functional architecture . 4 8.1 Content service coordination function 5 8.2 Content delivery control function . 5 8.3 Content delivery service func
21、tion . 5 9 Content delivery operations 6 9.1 Content publications . 6 9.2 Content service provisioning 7 9.3 Content routing . 7 9.4 Content caching 7 10 Informational flows 7 10.1 Content publication 7 10.2 Content service provisioning 9 10.3 Content routing . 10 10.4 Content caching 10 11 Environm
22、ental considerations 11 12 Security considerations . 11 13 Accessibility considerations . 11 Appendix I Use cases for context-aware content delivery 12 Bibliography. 14 Rec. ITU-T Y.3045 (01/2014) 1 Recommendation ITU-T Y.3045 Smart ubiquitous networks Functional architecture of content delivery 1 S
23、cope This Recommendation provides the functional architecture of content delivery in smart ubiquitous networks (SUN) by specifying the relevant capabilities, functions, operations and informational flows. The capabilities of content delivery in SUN are identified considering content-awareness ITU-T
24、Y.3044 and context-awareness ITU-T Y.3043 capabilities of SUN. 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 time of publication, the editions indicated were valid.
25、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. A list of the currently valid ITU-T Recommendations is
26、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.3041 Recommendation ITU-T Y.3041 (2013), Smart ubiquitous networks Overview. ITU-T Y.3043 Recommendation ITU-T Y.3043 (2013), Smart ubiquit
27、ous networks Context awareness framework. ITU-T Y.3044 Recommendation ITU-T Y.3044 (2013), Smart ubiquitous networks Content awareness framework. 3 Definitions 3.1 Terms defined elsewhere This Recommendation uses the following terms defined elsewhere: 3.1.1 content awareness ITU-T Y.3044, clause 6:
28、An ability to identify, retrieve and deliver contents efficiently based on the content-related information considering location and/or user. 3.1.2 context b-ITU-T Y.2002: The information that can be used to characterize the environment of a user. NOTE Context information may include where the user i
29、s, what resources (devices, access points, noise level, bandwidth, etc.) are near the user, at what time the user is moving, interaction history between person and objects, etc. According to specific applications, context information can be updated. 3.1.3 context awareness b-ITU-T Y.2201: Context aw
30、areness is a capability to determine or influence a next action in telecommunication or process by referring to the status of relevant entities, which form a coherent environment as a context. 3.1.4 Smart Ubiquitous Networks (SUN) ITU-T Y.3041: IP-based packet networks that can provide transport and
31、 delivery of a wide range of existing and emerging services to people and things. The services provided by the SUN can cover aspects such as control, processing and storage. NOTE 1 The network is smart in the sense that it is knowledgeable, context-aware, adaptable, autonomous, programmable and can
32、effect services effectively and securely. NOTE 2 The network is ubiquitous in the sense that it allows access anytime anywhere through varied access technologies, access devices including end user devices, and human-machine interfaces. 2 Rec. ITU-T Y.3045 (01/2014) 3.2 Terms defined in this Recommen
33、dation None. 4 Abbreviations and acronyms This Recommendation uses the following abbreviations and acronyms: AAA Authentication, Authorization, and Accounting CN-FE Content Name resolution Functional Entity CP-FE Content Publication Functional Entity CR-FE Content Routing however, it is also exclude
34、d because the content-aware router finds a service failure on content source #3. Then, content-aware router decides that content source #2 has the optimal source and path to deliver the content to the user. Finally, the content-aware router redirects the users request to content source #2, which wil
35、l deliver the content. Figure I.1 shows a procedural flow for the aforementioned use cases for context-aware content delivery. Rec. ITU-T Y.3045 (01/2014) 13 Y.3045(14)_FI.16. Redirect to Content Source #23. Content request1. Request content2. Redirect to content sourceIP address 1.1.2.1UserContentp
36、roviderContext-awarerouterNetwork1.1.X.X 1.2.1.X 1.2.2.XContentsource #1Contentsource #2Contentsource #37. Content request (ContentID)8. Deliver content4. Extracting device context5. Select optimal content source based on context0. Analyse context informationOverlaodFailureResource and service conte
37、xt (cached list, load ratio, session count, average service timeNetwork context (routing information)Figure I.1 Use cases of context aware content delivery 1. Context-aware router collects the network context from the network by capturing dynamically changing routing information. 2. Context-aware ro
38、uter collects the service context from the content source by collecting periodically or dynamically changing service status such as a list of caches, load ratio, number of sessions, average service time, etc. 3. Context-aware router periodically or dynamically analyses the aggregated context informa
39、tion and summarizes the context information in the abstract format such as ranking. 4. Content source #1 is experiencing overload because of too many service sessions. 5. Content source #3 accidently encounters service failure. 1. The end user sends a content request to the content provider. 2. Cont
40、ent provider redirects the content request to the content source using HTTP redirection or DNS-based routing mechanisms, for example. 3. Content request is redirected to the context-aware router. 4. Context-aware router extracts the device context, if it exists, from the content request. 5. Context-
41、aware router selects the optimal content source based on the contexts and policies for determining content delivery paths. For example, if the network context has a high priority, content source #1 could be selected as the optimal source. But, in this example, content source #2 is selected because t
42、he context-aware router has a policy to consider both network and service context. In terms of service context, content source #3 is excluded because it does not have enough resources to deliver the content. 6-7. Content request is redirected to content source #2. 8. Content source #2 delivers the c
43、ontent requested. 14 Rec. ITU-T Y.3045 (01/2014) Bibliography b-ITU-T Y.2002 Recommendation ITU-T Y.2002 (2009), Overview of ubiquitous networking and of its support in NGN. b-ITU-T Y.2201 Recommendation ITU-T Y.2201 (2009), Requirements and capabilities for ITU-T NGN. Printed in Switzerland Geneva,
44、 2014 SERIES OF ITU-T RECOMMENDATIONS Series A Organization of the work of ITU-T Series D General tariff principles Series E Overall network operation, telephone service, service operation and human factors Series F Non-telephone telecommunication services Series G Transmission systems and media, di
45、gital systems and networks Series H Audiovisual and multimedia systems Series I Integrated services digital network Series J Cable networks and transmission of television, sound programme and other multimedia signals Series K Protection against interference Series L Construction, installation and pr
46、otection of cables and other elements of outside plant Series M Telecommunication management, including TMN and network maintenance Series N Maintenance: international sound programme and television transmission circuits Series O Specifications of measuring equipment Series P Terminals and subjectiv
47、e and objective assessment methods Series Q Switching and signalling Series R Telegraph transmission Series S Telegraph services terminal equipment Series T Terminals for telematic services Series U Telegraph switching Series V Data communication over the telephone network Series X Data networks, open system communications and security Series Y Global information infrastructure, Internet protocol aspects and next-generation networks Series Z Languages and general software aspects for telecommunication systems
