1、INTERNATIONAL TELECOMMUNICATION UNION ITU-T TELECOMMUNICATION STANDARDIZATION SECTOR OF ITU E.651 (03/2000) SERIES E: OVERALL NETWORK OPERATION, TELEPHONE SERVICE, SERVICE OPERATION AND HUMAN FACTORS Quality of service, network management and traffic engineering - Traffic engineering - Definitions R
2、eference connections for traffic engineering of IP access networks ITU-T Recommendation E.651 (Formerly CCITT Recommendation) ITU-T E-SERIES RECOMMENDATIONS OVERALL NETWORK OPERATION, TELEPHONE SERVICE, SERVICE OPERATION AND HUMAN FACTORS OPERA TION, NUMBERING, ROUTING AND MOBILE SERVICES INTERNATIO
3、NAL OPERATION Definitions General provisions Concerning Administrations General provisions concerning users Operation of international telephone services Numbering plan of the international telephone service International routing plan Tones in national signalling systems Numbering plan of the intern
4、ational telephone service Maritime mobile service and public land mobile service OPERATIONAL PROVISIONS RELATING TO CHARGING AND ACCOUNTING IN THE INTERNATIONAL TELEPHONE SERVICE Charging in the international telephone service Measuring and recording call durations for accounting purposes UTILIZATIO
5、N OF THE INTERNATIONAL TELEPHONE NETWORK FOR NON- TE LEP H ONY AP PLI CATI ONS General Phototelegraphy International routing plan QUALITY OF SERVICE, NETWORK MANAGEMENT AND TRAFFIC ENGINEERING NETWORK MANAGEMENT ISDN PROVISIONS CONCERNING USERS International service statistics International network
6、management Checking the quality of the international telephone service TRAFFIC ENGINEERING Measurement and recording of traffic Forecasting of traffic Determination of the number of circuits in manual operation Determination of the number of circuits in automatic and semi-automatic operation Grade o
7、f service Definitions ISDN traffic engineering Mobile network traffic engineering QUALITY OF TELECOMMUNICATION SERVICES: CONCEPTS, MODELS, OBJECTIVES AND DEPENDABILITY PLANNING Terms and definitions related to the quality of telecommunication services Models for telecommunication services Objectives
8、 for quality of service and related concepts of telecommunication services Use of quality of service objectives for planning of telecommunication networks Field data collection and evaluation on the performance of equipment, networks and services E. 1 00-E. 103 E.104-E.119 E. 120-E. 139 E. 140-E. 15
9、9 E. 160-E. 169 E. 170-E. 179 E. 180-E. 189 E. 190-E. 199 E.200-E.229 E.230-E.249 E.260-E.269 E.300-E.319 E.320-E.329 E.350-E.399 E.400-E.409 E.41 0-E.419 E.420-E.489 E.490-E.505 E.506-E509 E.510-E519 E.520-E539 E.540-E599 E.700-E.749 E.750-E.799 E.800-E.809 E.810-E.844 E.845-E.859 E.860-E.879 E.880
10、-E.899 For further details, please rer to ITD-T List of Recommendations. ITU-T RECOMMENDATION E.651 REFERENCE CONNECTIONS FOR TRAFFIC ENGINEERING OF IP ACCESS NETWORKS Summary This Recommendation provides reference connections and network configurations for IP access networks for the provision of IP
11、 telephony and TCP/IP-supported data services such as web- browsing, e-mail, file transfer and high-speed data access. Other services such as video telephony, video-on-demand, are for further study. Also, only point-to-point reference connections are considered in this release of the Recommendation.
12、 Source ITU-T Recommendation E.651 was prepared by ITU-T Study Group 2 (1997-2000) and was approved under the WTSC Resolution No. 1 procedure on 13 March 2000. Recommendation E.651 (03/2000) 1 FOREWORD ITU (International Telecommunication Union) is the United Nations Specialized Agency in the field
13、of telecommunications. The ITU Telecommunication Standardization Sector (ITU-T) is a permanent organ of the ITU. The 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. T
14、he World Telecommunication Standardization Conference (WTSC), which meets every four years, establishes the topics for study by the ITU-T Study Groups which, in their turn, produce Recommendations on these topics. The approval of Recommendations by the Members of the ITU-T is covered by the procedur
15、e laid down in WTSC Resolution No. 1. In some areas of information technology which fall within ITU-Ts purview, the necessary standards are prepared on a collaborative basis with IS0 and IEC. NOTE In this Recommendation, the expression “Administration“ is used for conciseness to indicate both a tele
16、communication administration and a recognized operating agency. INTELLECTUAL PROPERTY RIGHTS The ITU draws attention to the possibility that the practice or implementation of this Recommendation may involve the use of a claimed Intellectual Property Right. The ITU takes no position concerning the ev
17、idence, 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, the ITU had not received notice of intellectual property, protected by patents, w
18、hich may be required to implement this Recommendation. However, implementors are cautioned that this may not represent the latest information and are therefore strongly urged to consult the TSB patent database. o ITU 2000 All rights reserved. No part of this publication may be reproduced or utilized
19、 in any form or by any means, electronic or mechanical, including photocopying and microfilm, without permission in writing fi-om the ITU. 11 Recommendation E.651 (03/2000) CONTENTS 4 5 6 6.1 6.2 7 7.1 7.2 8 Scope . References . Definitions Abbreviations Introduction . Reference connections All-IP c
20、onnections Interworking with PSTN/ISDN 6.2.1 IP-to-PSTN/ISDN or PSTNASDN-to-IP . 6.2.2 IP-to-IP via PSTN/ISDN . 6.2.3 PSTN/ISDN-to-PSTN/ISDN via IP . Reference architectures . HFC systems . Other access technologies . History . Recommendation E.651 (032000) Page 1 1 2 2 3 7 . 111 Recommendation E.65
21、1 REFERENCE CONNECTIONS FOR TRAFFIC ENGINEERING OF IP ACCESS NETWORKS (Geneva, 2000) 1 Scope This Recommendation provides reference connections and network configurations for IP access networks for the provision of IP telephony and TCP/IP-supported data services such as web- browsing, e-mail, file t
22、ransfer and high-speed data access. Other services such as videotelephony, video-on-demand, are for further study. Also, only point-to-point reference connections are considered in this release of the Recommendation. Built upon the reference connections specified herein, other Recommendations in thi
23、s family contain the definitions of appropriate Grade of Service (GOS) parameters applicable to different types of IP access networks, taking into account the capabilities and limitations of different access technologies used. The intent is to facilitate the traffic-engineering tasks of developing t
24、raffic models, measurements, control and dimensioning methods for meeting Quality of Service objectives. For the purpose of this Recommendation, an IP access network is an infrastructure of network components with well-defined interfaces, protocols, and network management procedures architected with
25、 a specific access technology to provide access to IP-based applications such as IP telephony and TCP/IP-supported data services. Examples of access technologies include cable- modem-based hybrid fibrekoax (HFC) systems, a variety of digital subscriber line systems, wireless systems (both mobile and
26、 fixed), and high-speed analog modems. Two-way capability must be available in an IP access network to support interactive bidirectional communication. The first release of this Recommendation deals only with IP access networks based on HFC systems. Subsequent releases will include other access tech
27、nologies. 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
28、to revision; all 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. - ITU-T Recommendation E.726
29、 (2000), Network grade of service parameters and target values for B-ISDN. ITU-T Recommendation E. 67 1 (2000), Post-selection delay in PSTMISDNs using Internet telephony for a portion of the connection. ITU-T draft Recommendation E.hfc, Trafic engineering considerations for IP access networks based
30、 on hybrid Jbre-coaxial system. - ITU-T Recommendation J. 1 12 (1998), Transmission systems for interactive cable television services. ITU-T draft Recommendation Y. 123 1, IP access network architecture. - - - Recommendation E.651 (03/2000) 1 The following references are listed here for information.
31、 - DOCSIS 1, Data-Over-Cable Service Interface Specifications, Radio Frequency Interface Specification, Cable Television Laboratories, Inc. DOCSIS2, Data-Over-Cable Service Interface Specifications, Cable Modem to Customer Premises Equipment Interface Specification, SP-RFIv1 . l -102-99073 1, Cable
32、Television Laboratories, Inc. - 3 Definitions The following definitions given in Recommendation J. 1 12 are repeated herein for ease of reference. 3.1 Cable Modem (CM): A modulator-demodulator at subscriber locations intended for use in conveying data communications on a cable television system. 3.2
33、 Cable Modem Termination System (CMTS): Located at the cable television system headend or distribution hub, provides complementary functionality to the cable modems to enable data connectivity to a wide-area network. 3.3 fibre node: A point of interface between a fibre trunk and the coaxial distribu
34、tion. 3.4 Hybrid Fibre/Coax (HFC) system: A broadband bidirectional shared-media transmission system using fibre trunks between the headend and the fibre nodes, and coaxial distribution from the fibre nodes to the customer locations. The following definitions given in draft Recommendation Y.1231 are
35、 repeated herein for ease of reference. 3.5 IP access network: An implementation comprising network entities to provide the required access capabilities between an “IP user“ and an “IP service provider“ for the provision of IP services. “IP user“ and “IP service provider“ are logical entities which
36、terminate the IP layer and/or IP related functions. 3.6 NOTE - IP access network as described in clause 1 and used herewith for traffic engineering purposes includes a local P network and may include an P service provider. See Note 1 in Figure 6-1. See also Figure 7-1 for an illustrative reference a
37、rchitecture. IP core network: IP service providers network, including one or more IP service providers. 4 Abbreviations This Recommendation uses the following abbreviations: CM CMTS CPE CPN GOS HFC IP ISDN MTA PSTN 2 Cable Modem Cable Modem Termination System Customer-Premises Equipment Customer-Pre
38、mises Network Grade of Service Hybrid FibreKOax system Internet Protocol Integrated Services Digital Network Multimedia Terminal Adapter Public Switched Telephone Network Recommendation E.651 (03/2000) QOS Quality of Service TCP Transmission Control Protocol UNI User-Network Interface VOIP Voice Ove
39、r IP 5 Introduction IP-based networks are being used to develop integrated broadband networks for the delivery of diverse types of IP-based voice and data services. To gain access to such services efficiently on a mass scale, IP access networks are provisioned according to customer demands. To meet
40、Quality of Service (QOS) objectives to customers of IP access networks, network operators use Grade of Service (GOS) parameters and their associated target values as internal design objectives. This Recommendation provides reference connections and access network configurations so that network GOS p
41、arameters can be defined and their associated target values specified. The appropriate GOS parameters applicable to different IP access network types based on different access technologies are specified in other Recommendations of this family. These Recommendations may also contain relevant traffic
42、principles such as user demand models, traffic models, measurements, control and dimensioning methods for the planning, operation, and management of the particular IP access networks. In addition to this Recommendation, the family of IP access network traffic-engineering Recommendations currently co
43、nsists of Recommendation E. 67 1 and draft Recommendation E.hfc. Recommendations for IP access networks based on other access technologies are to be added in the future. 6 Reference connections This clause specifies generic reference connections that are independent of access technology. Intenvorkin
44、g with PSTN/ISDN is also considered. Three categories of reference connections are specified: o national, local area; o national, long distance; o international. The term “national local area“ refers to a connection whose UNI-to-UNI straight-line geographic distance is relatively short. This distanc
45、e is usually of the order of 150 kilometres or less (see Notes 1 and 2 below); typically this would be within a greater metropolitan area. The term “national long distance“ refers to a connection whose UNI-to-UNI straight-line geographic distance is more than the value for “national local area“, and
46、 is within a single country. Typically, though not necessarily, a “national local area“ connection is supported by a single public network provider, while a “national long distance“ connection is supported typically by one to three public network providers. NOTE 1 - Annex B/J.112 specifies “a maximu
47、m optical/electrical spacing between the cable modem termination system and the most distant cable modem of 100 miles, although typical maximum separation may be 10-15 miles“. NOTE 2 - Recommendation E.726 specifies a “national local area“ connection to be one whose UNI-to-UNI straight-line geograph
48、ic distance does not exceed 1 O0 kilometres. NOTE 3 - The category of “national, long distance“ connections may include a sub-category of connections referred to as “national, intermediate distance“ connections. The UNI-to-UNI straight-line geographic distance of these connections does not exceed 10
49、00 kilometres, but exceeds that for “national, local area“ connections. Recommendation E.651 (03/2000) 3 6.1 All-IP connections Figure 6-1 shows the above types of reference connections in the case of an all-IP connection on an end-to-end basis. The IP core network “cloud“ in the diagram is intended to denote a combination of national intermediate-distance, national long-distance and/or international IP service provider networks, and may thus consist of several IP-based networks in tandem. IP core network provides interconnection between domains. In these reference connections, a customer-
