1、 I n t e r n a t i o n a l T e l e c o m m u n i c a t i o n U n i o n ITU-T Y.3512 TELECOMMUNICATION STANDARDIZATION SECTOR OF ITU (08/2014) SERIES Y: GLOBAL INFORMATION INFRASTRUCTURE, INTERNET PROTOCOL ASPECTS AND NEXT-GENERATION NETWORKS Cloud Computing Cloud computing Functional requirements of
2、 Network as a Service Recommendation ITU-T Y.3512 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
3、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, access, network capabil
4、ities 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 IPTV over NGN Y.1900Y.1999 NEXT GENERATION NETWORKS
5、 Frameworks 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 Enhancements to NGN Y.2300Y.2399 Netw
6、ork management Y.2400Y.2499 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.3499 CLOUD COMPUTING Y.3500Y.3999 For further details, p
7、lease refer to the list of ITU-T Recommendations. Rec. ITU-T Y.3512 (08/2014) i Recommendation ITU-T Y.3512 Cloud computing Functional requirements of Network as a Service Summary Recommendation ITU-T Y.3512 describes the concept of Network as a Service (NaaS) and its functional requirements. It pro
8、vides typical use cases of NaaS and specifies the functional requirements of three aspects, ranging from NaaS application, NaaS platform and NaaS connectivity which are based on the corresponding uses cases and cloud capabilities types. History Edition Recommendation Approval Study Group Unique ID*
9、1.0 ITU-T Y.3512 2014-08-29 13 11.1002/1000/12285 Keywords Cloud computing, Network as a Service, NaaS, NaaS application, NaaS connectivity, NaaS platform. _ * To access the Recommendation, type the URL http:/handle.itu.int/ in the address field of your web browser, followed by the Recommendations u
10、nique ID. For example, http:/handle.itu.int/11.1002/1000/11830-en. ii Rec. ITU-T Y.3512 (08/2014) FOREWORD The International Telecommunication Union (ITU) is the United Nations specialized agency in the field of telecommunications, information and communication technologies (ICTs). The ITU Telecommu
11、nication 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 them with a view to standardizing telecommunications on a worldwide basis. The World Telecommunication Standardization Assem
12、bly (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-T Recommendations is covered by the procedure laid down in WTSA Resolution 1. In some areas of information technology whic
13、h 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 for conciseness to indicate both a telecommunication administration and a recognized operating agency. Compliance with th
14、is Recommendation is voluntary. However, 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 lang
15、uage 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 any party. INTELLECTUAL PROPERTY RIGHTSITU draws attention to the possibility that the practice or implementation of this R
16、ecommendation may involve the use of 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
17、 approval of this Recommendation, ITU had not 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
18、 TSB patent database at http:/www.itu.int/ITU-T/ipr/. ITU 2015 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.3512 (08/2014) iii Table of Contents Page 1 Scope . 1 2 References . 1 3 Definitions 1
19、 3.1 Terms defined elsewhere 1 3.2 Terms defined in this Recommendation . 2 4 Abbreviations and acronyms 2 5 Conventions 4 6 General description . 4 6.1 Networking challenges in cloud computing . 4 6.2 High-level concept of NaaS 5 7 Functional requirements of NaaS application . 6 7.1 Performance 7 7
20、.2 Operation and management 7 7.3 Service chain 7 7.4 Multiple IP addresses . 7 8 Functional requirements of NaaS platform . 7 8.1 Programmable NaaS platform 7 8.2 Dynamic and flexible network services composition and steering 8 8.3 Isolation of service chains for tenants 8 8.4 Flexible scaling of N
21、aaS platform 8 8.5 Integration of software applications . 8 9 Functional requirements of NaaS connectivity . 8 9.1 Common control mechanism for NaaS connectivity 8 9.2 Unified SLA for multiple optimized networks . 8 9.3 Leveraging transport networks dynamically 9 9.4 Unified network control mechanis
22、m 9 9.5 Elastic network reconfiguration . 9 9.6 Seamless and end-to-end solution of bandwidth allocation . 9 9.7 Symmetric or asymmetric capacity 9 9.8 Optimized and fine-grained traffic engineering . 9 9.9 Coexistence with legacy network services and functions 9 9.10 Centralized control view and ab
23、straction view of resources 9 9.11 CSC limited control of services 10 9.12 Logically isolated network partition . 10 9.13 Overlay network mechanism 10 9.14 Overlapped private IP addresses 10 9.15 Interworking among different VPN solutions 10 9.16 VPN connection in mobile environment 10 iv Rec. ITU-T
24、 Y.3512 (08/2014) Page 9.17 Connection to NaaS CSPs network through public Internet 10 10 Security considerations . 10 Appendix I Development methodology of NaaS functional requirements and architecture . 11 Appendix II Use cases of NaaS. 12 II.1 Use case template . 12 II.2 NaaS applications related
25、 use cases . 12 II.3 NaaS platform related use cases . 15 II.4 NaaS connectivity related use cases . 17 Appendix III Considerations on CSPs network related activities 26 Bibliography. 28 Rec. ITU-T Y.3512 (08/2014) 1 Recommendation ITU-T Y.3512 Cloud computing Functional requirements of Network as a
26、 Service 1 Scope This Recommendation provides use cases and functional requirements of Network as a Service (NaaS), one of the representative cloud service categories. This Recommendation covers the following: High-level concept of NaaS; Functional requirements of NaaS; Typical NaaS use cases. This
27、Recommendation provides use cases and functional requirements of NaaS application, NaaS platform and NaaS connectivity. NOTE General requirements of NaaS can be found in ITU-T Y.3501. 2 References The following ITU-T Recommendations and other references contain provisions which, through reference in
28、 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 revision; users of this Recommendation are therefore encouraged to investigate the possibility of applying the most recent
29、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 this Recommendation does not give it, as a stand-alone document, the status of a Recommendation. ITU-T X.1601 Recommendatio
30、n ITU-T X.1601 (2014), Security framework for cloud computing. ITU-T Y.3011 Recommendation ITU-T Y.3011 (2012), Framework of network virtualization for future networks. ITU-T Y.3500 Recommendation ITU-T Y.3500 (2014), Information technology Cloud computing Overview and Vocabulary. ITU-T Y.3501 Recom
31、mendation ITU-T Y.3501 (2013), Cloud computing framework and high-level requirements. ITU-T Y.3502 Recommendation ITU-T Y.3502 (2014), Information technology Cloud computing Reference architecture. 3 Definitions 3.1 Terms defined elsewhere This Recommendation uses the following terms defined elsewhe
32、re: 3.1.1 application capabilities type ITU-T Y.3500: Cloud capabilities type in which the cloud service customer can use the cloud service providers applications. 3.1.2 cloud capabilities type ITU-T Y.3500: Classification of the functionality provided by a cloud service to the cloud service custome
33、r, based on resource used. NOTE The cloud capabilities types are application capabilities type, infrastructure capabilities type and platform capabilities type. 2 Rec. ITU-T Y.3512 (08/2014) 3.1.3 cloud computing ITU-T Y.3500: Paradigm for enabling network access to a scalable and elastic pool of sh
34、areable physical or virtual resources with self-service provisioning and administration on-demand. NOTE Examples of resources include servers, operating systems, networks, software, applications, and storage equipment. 3.1.4 cloud service ITU-T Y.3500: One or more capabilities offered via cloud comp
35、uting invoked using a defined interface. 3.1.5 cloud service category ITU-T Y.3500: Group of cloud services that possess some common set of qualities. NOTE A cloud service category can include capabilities from one or more cloud capabilities types. 3.1.6 cloud service customer ITU-T Y.3500: Party wh
36、ich is in a business relationship for the purpose of using cloud services. 3.1.7 cloud service provider ITU-T Y.3500: Party which makes cloud services available. 3.1.8 cloud service user ITU-T Y.3500: Natural person, or entity on their behalf, associated with a cloud service customer that uses cloud
37、 services. 3.1.9 Communications as a Service (CaaS) ITU-T Y.3500: Cloud service category in which the capability provided to the cloud service customer is real time interaction and collaboration. NOTE CaaS can provide both application capabilities type and platform capabilities type. 3.1.10 infrastr
38、ucture capabilities type ITU-T Y.3500: Cloud capabilities type in which the cloud service customer can provision and use processing, storage and networking resources. 3.1.11 logically isolated network partition ITU-T Y.3011: A network that is composed of multiple virtual resources which is isolated
39、from other LINPs. NOTE Term “logically isolated“, which is the counter concept of “physically isolated“, means mutual exclusiveness of the subjects (e.g., network partition, in this case), while the original subjects may be physically united/shared within the common physical constraints. 3.1.12 Netw
40、ork as a Service (NaaS) ITU-T Y.3500: Cloud service category in which the capability provided to the cloud service customer is transport connectivity and related network capabilities. NOTE NaaS can provide any of the three cloud capabilities types. 3.1.13 platform capabilities type ITU-T Y.3500: Clo
41、ud capabilities type in which the cloud service customer can deploy, manage and run customer-created or customer-acquired applications using one or more programming languages and one or more execution environments supported by the cloud service provider. 3.1.14 tenant ITU-T Y.3500: Group of cloud se
42、rvice users sharing access to a set of physical and virtual resources. 3.2 Terms defined in this Recommendation This Recommendation defines the following term: 3.2.1 service chain: An ordered set of functions that is used to enforce differentiated traffic handling policies for a traffic flow. 4 Abbr
43、eviations and acronyms This Recommendation uses the following abbreviations and acronyms: BGP Border Gateway Protocol Rec. ITU-T Y.3512 (08/2014) 3 BoD Bandwidth on Demand BSS Business Support System CaaS Communications as a Service CDN Content Delivery Network CPE Customer Premises Equipment CSC Cl
44、oud Service Customer CSP Cloud Service Provider CSU Cloud Service User DNS Domain Name System DPI Deep Packet Inspection EPC Evolved Packet Core GW Gateway HQ Headquarter IaaS Infrastructure as a Service IDE Integrated Development Environment IMS IP Multimedia Subsystem IP Internet Protocol IPS Intr
45、usion Protection System IPsec IP security L2 Layer 2 L3 Layer 3 LAN Local Area Network LINP Logically Isolated Network Partition MAC Medium Access Control MEF Metro Ethernet Forum MEN Metro Ethernet Network MPLS Multi-Protocol Label Switching NaaS Network as a Service NNI Network-to-Network Interfac
46、e NOS Network Operating System OSS Operations Support System QoE Quality of Experience QoS Quality of Service P2P Peer-to-Peer PaaS Platform as a Service PoP Point of Presence SaaS Software as a Service 4 Rec. ITU-T Y.3512 (08/2014) SAL Software Abstraction Layer SDN Software Defined Networking SLA
47、Service Level Agreement SSL Secure Socket Layer UNI User-to-Network Interface vCDN virtual Content Delivery Network vDPI virtual Deep Packet Inspection vEPC virtualised Evolved Packet Core vFW virtual Firewall vRouter virtual Router VDI Virtual Desktop Infrastructure VM Virtual Machine VoIP Voice ov
48、er IP VPLS Virtual Private LAN Service VPN Virtual Private Network VRF Virtual Routing and Forwarding WAN Wide Area Network 5 Conventions The keywords “is required to“ indicate a requirement which must be strictly followed and from which no deviation is permitted if conformance to this Recommendatio
49、n is to be 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 “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 implementation must provide the option and the feat
