1、 International Telecommunication Union ITU-T Y.3044TELECOMMUNICATION STANDARDIZATION SECTOR OF ITU (08/2013) SERIES Y: GLOBAL INFORMATION INFRASTRUCTURE, INTERNET PROTOCOL ASPECTS AND NEXT-GENERATION NETWORKS Future networks Smart ubiquitous networks Content awareness framework Recommendation ITU-T
2、Y.3044 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.400Y.499 Numberi
3、ng, 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 management Y.1200Y.1299
4、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 architecture mod
5、els 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 Network control
6、 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 ITU-T Recommendat
7、ions. Rec. ITU-T Y.3044 (08/2013) i Recommendation ITU-T Y.3044 Smart ubiquitous networks Content awareness framework Summary Recommendation ITU-T Y.3044 describes a framework for the content awareness feature of smart ubiquitous networks (SUN). The content awareness feature of SUN considers enhance
8、d capabilities to enable networks to optimally and efficiently handle the content. This Recommendation describes the concept, functional requirements and functional model of content awareness of SUN. History Edition Recommendation Approval Study Group 1.0 ITU-T Y.3044 2013-08-13 13 Keywords Content
9、awareness, SUN. ii Rec. ITU-T Y.3044 (08/2013) 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-T) is a perman
10、ent 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 years, establish
11、es 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 necessary standar
12、ds 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. However, the Recomm
13、endation 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 equivalents ar
14、e 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 of a claimed Int
15、ellectual 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, ITU had received
16、 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.int/ITU-T/ipr/.
17、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.3044 (08/2013) iii Table of Contents Page 1 Scope 1 2 References. 1 3 Definitions 1 3.1 Terms defined elsewhere 1 3.2 Terms defined in this
18、Recommendation . 2 4 Abbreviations and acronyms 2 5 Conventions 2 6 Overview 3 7 Functional requirements . 4 7.1 Content discovery . 4 7.2 Content caching 4 7.3 Content distribution 5 8 Functional model of content awareness 5 8.1 Overview of functional model 5 8.2 Content service coordination functi
19、on 6 8.3 Content delivery control function . 7 9 Environmental considerations 8 10 Security considerations . 8 11 Accessibility considerations . 8 Appendix I Examples of content descriptors 9 I.1 Content descriptor 9 Appendix II Example mechanisms for content awareness framework . 10 II.1 Content pu
20、blication 10 II.2 Request routing . 10 II.3 Content routing . 11 II.4 Content distribution and caching 13 Bibliography. 14 Rec. ITU-T Y.3044 (08/2013) 1 Recommendation ITU-T Y.3044 Smart ubiquitous networks Content awareness framework 1 Scope This Recommendation describes a framework for content awa
21、reness feature of smart ubiquitous networks (SUN). The content awareness feature of SUN considers enhanced capabilities to enable networks to optimally and efficiently handle the content. This Recommendation covers the following: the concept of content awareness; functional requirements to support t
22、he content awareness feature; the functional model for content awareness of SUN. While the high-level requirements of the content awareness feature of SUN are covered in ITU-T Y.3041, this Recommendation specifies the detailed functional requirements to realize the capability of content awareness of
23、 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. All Recommendations and other references are subject to r
24、evision; 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 regularly published. The reference to a document within t
25、his 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. 3 Definitions 3.1 Terms defined elsewhere This Recommendation uses the following terms defined elsewhere: 3.1.1 content
26、 b-ITU-T X.1161: Information created by individuals, institutions and technology to benefit audiences in contexts that they value. 3.1.2 context b-ITU-T Y.2002: The information that can be used to characterize the environment of a user. 3.1.3 context awareness b-ITU-T Y.2201: Context-awareness is th
27、e 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 delivery o
28、f 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 perform se
29、rvices 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.3044 (08/2013) 3.2 Terms defined in this Recommendation
30、 None. 4 Abbreviations and acronyms This Recommendation uses the following abbreviations and acronyms: AAA Authentication, Authorization and Accounting CDN Content Delivery Network CP Content Provider DDoS Distributed Denial of Service DNS Domain Name System FE Functional Entity HD High Definition H
31、TTP Hyper Text Transfer Protocol ID Identifier IP Internet Protocol OSPF Open Shortest Path First QoS Quality of Service SD Standard Definition SUN Smart Ubiquitous Networks URL Uniform Resource Locator 5 Conventions In this Recommendation: The keywords “is required to“ indicate a requirement which
32、must be strictly followed and from which no deviation is permitted, if conformance to this Recommendation is to be claimed. The keywords “is prohibited from“ indicate a requirement which must be strictly followed and from which no deviation is permitted, if conformance to this Recommendation is to b
33、e claimed. The keywords “is recommended“ indicate a requirement which is recommended but which is not absolutely required. Thus, this requirement need not be present to claim conformance. The keywords “is not recommended“ indicate a requirement which is not recommended but which is not specifically
34、prohibited. Thus, conformance with this Recommendation can still be claimed even if this requirement is present. The keywords “can optionally“ indicate an optional requirement which is permissible, without implying any sense of being recommended. This term is not intended to imply that the vendors i
35、mplementation must provide the option, and the feature can be optionally enabled by the network operator/service provider. Rather, it means the vendor may optionally provide the feature and still claim conformance to this Recommendation. Rec. ITU-T Y.3044 (08/2013) 3 6 Overview Smart ubiquitous netw
36、orks (SUN) are IP-based packet networks that can provide transport and delivery of a wide range of existing and emerging services to people and things ITU-T Y.3041. The services provided by the SUN cover aspects such as control, processing and storage. Content awareness is a key feature of SUN to su
37、pport an optimized content delivery service. Content awareness is an ability to identify, retrieve and deliver contents efficiently based on the content-related information considering location and/or user. Using this feature, SUN identifies content by its name or other relevant information (i.e., m
38、etadata) to deliver and retrieve the content efficiently. It can prevent the duplicated transmission of the same contents by content routing and delivery with the content name. Content caching (i.e., in-network caching) and delivery in the node close to users can provide a high-quality video streami
39、ng service for surges of content requests. The content awareness feature of SUN provides the following capabilities: Content discovery: Discover the content location for content storages or caches by content name (i.e., name-based content routing) rather than its location-dependent identifier (e.g.,
40、 IP address). The name-based content routing allows the end users to access content by the content name regardless of the change of the location of content as well as of the end users. The content or content location can be dynamically determined according to the content metadata or the location of
41、the end users for optimized content delivery. The name-based content routing also prevents content sources from being damaged by attack such as DDoS because it hides the network locations (e.g., IP addresses) of content sources susceptible to exterior ill-intentioned threats. Content caching: Stores
42、 and caches the content in the storage of SUN nodes. It can reduce transfer delays and network costs due to large distances between content sources and end users. Based on the content caches, SUN provide end users content proximity information such network topology and regional network cost for cont
43、ent delivery. Locality of the content provision gives content provider the benefit of saving costs and proximity-based content delivery gives the end users a better content delivery QoS. Content distribution: Dynamically distribute content, which is in caches and storages in the network according to
44、 traffic load, usage and user location, taking QoS and traffic optimization into account. The popular content may be distributed to the SUN nodes which are close to end users. Multiple requests for the same content from different end users can be served together along a single multicast spanning tre
45、e. This results in efficient content delivery and traffic optimization. These capabilities for content awareness are performed by dedicated SUN nodes, i.e., content nodes, which are deployed at strategic locations in the network. They are connected by logical links and form a logical network (i.e.,
46、content overlay network) over which content routing and delivery are provided. Published content over the content overlay network is to be identified with mappings to the specific locations of the overlaid network. For content awareness capabilities, the content can be discovered, cached, and distri
47、buted as file-level or chunk-level in SUN. 4 Rec. ITU-T Y.3044 (08/2013) 7 Functional requirements Functional requirements for content awareness are summarized as follows: 7.1 Content discovery SUN are required to provide the capability to identify content by name or ID. NOTE 1 The content name or I
48、D can be used to identify content at the file level and/or chunk level. The content name or ID is required to be unique in a global scale or in a local scale with mapping mechanisms. SUN are required to provide the capability of content namespace management. SUN are required to provide the capabilit
49、y to register and retrieve the content metadata which describes the content properties such as content creator/provider, date of creation and content location, etc. NOTE 2 The content metadata can be maintained either centralized or distributed. SUN are required to provide the capability to search the content using content name or content ID. SUN are required to provide the capability to determine the location of the content when it is published in the network. SUN are required to pr
