1、 International Telecommunication Union ITU-T Y.1530TELECOMMUNICATION STANDARDIZATION SECTOR OF ITU (11/2007) SERIES Y: GLOBAL INFORMATION INFRASTRUCTURE, INTERNET PROTOCOL ASPECTS AND NEXT-GENERATION NETWORKS Internet Protocol aspects Quality of service and network performance +- Call processing per
2、formance for voice service in hybrid IP networks ITU-T Recommendation Y.1530 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
3、Network 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 Architectu
4、re, 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
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 Numbering, naming and addressing Y.23
6、00Y.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. ITU-T Rec. Y.1530 (11/2007) i ITU-T Recommendation Y.1530 Call processing
7、performance for voice service in hybrid IP networks Summary ITU-T Recommendation Y.1530 defines performance parameters and objectives for point-to-point call processing for voice service provided by hybrid IP networks. The parameter definitions are based on the principles and generic performance par
8、ameters defined in ITU-T Recommendation I.350, and make use of relevant definitions from ISDN call processing performance Recommendations where appropriate. Source ITU-T Recommendation Y.1530 was approved on 13 November 2007 by ITU-T Study Group 12 (2005-2008) under the ITU-T Recommendation A.8 proc
9、edure. ii ITU-T Rec. Y.1530 (11/2007) 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 permanent organ
10、 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, establishes the to
11、pics 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 standards are pr
12、epared 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 Recommendation
13、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 are used to e
14、xpress 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 Intellectual P
15、roperty 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 not received notice
16、 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/. ITU 200
17、8 All rights reserved. No part of this publication may be reproduced, by any means whatsoever, without the prior written permission of ITU. ITU-T Rec. Y.1530 (11/2007) iii CONTENTS Page 1 Scope 1 2 References. 1 3 Definitions 2 4 Abbreviations and acronyms 2 5 Reference model . 3 5.1 Reference confi
18、guration . 3 5.2 Reference events. 4 5.3 Performance objectives for delay parameters. 4 5.4 Alternate specification of objectives 4 6 Call processing delays 4 6.1 Call establishment delays . 5 6.2 Call disengagement delays . 6 6.3 Registration delay (RD) 7 6.4 Deregistration delay (DD) 8 7 Accuracy
19、and dependability parameters and objectives. 8 7.1 Access parameters 8 7.2 Disengagement parameters. 10 8 Security. 11 Annex A Call set-up timers. 12 Appendix I Reference model for TIPHON scenario 2 13 Appendix II Measurement methods for estimating VoIP signalling performance . 16 II.1 Performance p
20、arameters to be measured 16 II.2 Measurement architectures. 16 II.3 Measurement methods using CM/CM architecture 18 II.4 Access function VoIP signalling measurement methods . 19 II.5 Disengagement function VoIP measurement methods. 21 Appendix III BICC architecture 23 Appendix IV New call processing
21、 QoS class structure 24 Bibliography. 26 ITU-T Rec. Y.1530 (11/2007) 1 ITU-T Recommendation Y.1530 Call processing performance for voice service in hybrid IP networks 1 Scope This Recommendation defines performance parameters and objectives for point-to-point call processing in voice service provide
22、d by hybrid IP networks. Call processing delay parameters for ISDN are defined in ITU-T I.352. Call processing accuracy and dependability parameters for ISDN are defined in ITU-T I.359. The parameters defined in this Recommendation are general in that no particular hybrid IP network call processing
23、protocol is assumed. The protocols used at different signalling interfaces traversed in processing a particular call may differ, and may include (for example) SIP, H.323 and BICC. Call processing protocol events defined in ISDN Recommendations are used for illustration in some cases. Call processing
24、 performance measurement architectures are presented in Appendix II. The parameters defined in this Recommendation are applicable only when the network is available. Assessment of the availability of hybrid IP networks is not addressed in this Recommendation. Table 1 illustrates the application of t
25、he three generic performance criteria defined in ITU-T I.350 to the call processing functions defined for hybrid IP networks. Table 1 Performance parameters for call processing functions Call processing function Speed Accuracy Dependability 1) Connection set-up Connection set-up delay Connection pos
26、t-selection delay (Note 1) Connection answer signal delay (Note 1) Connection set-up error probability Connection set-up failure probability 2) Connection disengagement Connection disconnect delay Connection release delay (Note 2) Connection premature disconnect probability Connection clearing failu
27、re probability NOTE 1 These parameters are defined for traffic engineering; objectives are not set for network performance. NOTE 2 This parameter has local significance only; objectives are not set. 2 References The following ITU-T Recommendations and other references contain provisions which, throu
28、gh 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 revision; users of this Recommendation are therefore encouraged to investigate the possibility of applying t
29、he 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 this Recommendation does not give it, as a stand-alone document, the status of a Recommendation. ITU-T E.671
30、 ITU-T Recommendation E.671 (2000), Post-selection delay in PSTN/ISDN networks using Internet telephony for a portion of the connection. ITU-T H.225.0 ITU-T Recommendation H.225.0 (2003), Call signalling protocols and media stream packetization for packet-based multimedia communication systems. 2 IT
31、U-T Rec. Y.1530 (11/2007) ITU-T H.245 ITU-T Recommendation H.245 (2003), Control protocol for multimedia communication. ITU-T H.323 ITU-T Recommendation H.323 (2003), Packet-based multimedia communications systems. ITU-T H.450.1 ITU-T Recommendation H.450.1 (1998), Generic functional protocol for th
32、e support of supplementary services in H.323. ITU-T I.350 ITU-T Recommendation I.350 (1993), General aspects of quality of service and network performance in digital networks, including ISDNs. ITU-T I.352 ITU-T Recommendation I.352 (1993), Network performance objectives for connection processing del
33、ays in an ISDN. ITU-T I.359 ITU-T Recommendation I.359 (1999), Accuracy and dependability of ISDN 64 kbit/s circuit-mode connection types. ITU-T Q.764 ITU-T Recommendation Q.764 (1999), Signalling System No. 7 ISDN User Part signalling procedures. ITU-T Q.931 ITU-T Recommendation Q.931 (1998), ISDN
34、user-network interface layer 3 specification for basic call control. ITU-T Y.1540 ITU-T Recommendation Y.1540 (2002), Internet protocol data communication service IP packet transfer and availability performance parameters. 3 Definitions This Recommendation defines the following terms: 3.1 end-to-end
35、 call processing performance: Network performance for call processing from UNI to UNI. 3.2 hybrid IP networks: Networks in which end-to-end services are provided through interworking between IP-based networks and networks employing other technologies, e.g., PSTN, ISDN, xDSL and CATV. 4 Abbreviations
36、 and acronyms This Recommendation uses the following abbreviations and acronyms: ACM Address Complete Message ANM Answer Message BICC Bearer Independent Call Control CASD Connection Answer Signal Delay CCFP Connection Clearing Failure Probability CDD Connection Disconnect Delay CPDP Connection Prema
37、ture Disconnect Probability CPDS Connection Premature Disconnect Stimulus CPE Customer Premises Equipment CPSD Connection Post Selection Delay CRD Connection Release Delay CSD Connection Set-up Delay ITU-T Rec. Y.1530 (11/2007) 3 CSEP Connection Set-up Error Probability CSFP Connection Set-up Failur
38、e Probability DD Deregistration Delay FFS For Further Study HRX Hypothetical Reference Connection IAM Initial Address Message ISDN Integrated Services Digital Network IWF InterWorking Function MP Measurement Point MPT Measurement Point Terminal RD Registration Delay RE Reference Event REL Release SC
39、N Switched Circuit Network SCTP Stream Control Transmission Protocol SIP Session Initiation Protocol TE Terminal Equipment UNI User-Network Interface VoIP Voice over Internet Protocol 5 Reference model Within the context of this Recommendation, a reference model is intended to establish the context
40、for the definition of performance parameters and the specification of objectives. This reference model provides a baseline reference connection that includes measurement points at which performance-significant reference events are observed and values for call processing performance parameters are de
41、termined, and a specification of the traffic loading conditions under which objectives are to be met. This reference model consists of a reference configuration, a set of performance-significant reference events, and time intervals for establishing the conditions under which objectives are to be met
42、. 5.1 Reference configuration The general reference configuration used in describing the call processing performance of voice service provided by hybrid IP networks is illustrated in Figure 1. Figure 1 General reference configuration 4 ITU-T Rec. Y.1530 (11/2007) A reference configuration for ISDN/I
43、P networking under TIPHON scenario 2 is described in Appendix I. A reference architecture for BICC is illustrated in Appendix III. 5.2 Reference events The reference events in ISDN can be uniquely specified by ITU-T I.352 and ITU-T I.359 based on signalling protocols in ITU-T Q.931 and ITU-T Q.764,
44、but the call processing reference events in IP networks depend on the method used for IP telephony, such as H.323, BICC and SIP. Therefore, the general model of reference events in this Recommendation should be based on a model composed of pairs of portion boundaries (Bi, Bj) in Figure 1 and exit an
45、d entry events at (Bi, Bj) uniquely. 5.3 Performance objectives for delay parameters End-to-end delay parameters are defined using reference events, therefore, performance objectives applied to this set of parameters reflect the quality of service provided by a providers network. The performance obj
46、ectives for the set of delay parameters can be expressed in terms of: mean delay; and 95%-ile delay. However, this approach does not take into account the impact of traffic load on call processing performance parameters (i.e., speed, dependability and accuracy). An alternative worst-case objective i
47、s addressed in clause 5.4. Assumptions regarding the call set-up attempt rate are stated in Annex A. 5.4 Alternate specification of objectives In general, while the value taken by a particular call processing performance parameter is sensitive to the traffic load that exists on each portion of the n
48、etwork through which a call is being processed, the worst-case objectives specified in this Recommendation are meant to apply to any one hour of time. NOTE To allow for the impact of random, short-term traffic load fluctuations during any hour, the probability that a particular call processing perfo
49、rmance parameter value, V, fails to meet its objective, O, may be specified. That is: Prob V O X where: V = actual parameter value O = objective The exact conditions or assumptions under which these worst-case objectives may apply are for further study. Use of an hour or possibly 15-minute interval of time would facilitate support by existing operations systems. It is recognized that the objective would be developed taking into consideration peak traffic factors such as “busy hour“. 6 Call processing del
