ITU-T Q 115 0-2002 Protocols for the control of signal processing network elements and functions《回声控制器的控制逻辑》.pdf

1、 INTERNATIONAL TELECOMMUNICATION UNION ITU-T Q.115.0TELECOMMUNICATION STANDARDIZATION SECTOR OF ITU (12/2002) SERIES Q: SWITCHING AND SIGNALLING Clauses applicable to ITU-T standard systems Logic and protocols for the control of signal processing network elements and functions Protocols for the cont

2、rol of signal processing network elements and functions ITU-T Recommendation Q.115.0 ITU-T Q-SERIES RECOMMENDATIONS SWITCHING AND SIGNALLING SIGNALLING IN THE INTERNATIONAL MANUAL SERVICE Q.1Q.3 INTERNATIONAL AUTOMATIC AND SEMI-AUTOMATIC WORKING Q.4Q.59 FUNCTIONS AND INFORMATION FLOWS FOR SERVICES I

3、N THE ISDN Q.60Q.99 CLAUSES APPLICABLE TO ITU-T STANDARD SYSTEMS Q.100Q.119 General clauses Q.100Q.109 Transmission clauses for signalling Q.110Q.114 Logic and protocols for the control of signal processing network elements and functions Q.115 Abnormal conditions Q.116Q.119 SPECIFICATIONS OF SIGNALL

4、ING SYSTEM No. 4 Q.120Q.139 SPECIFICATIONS OF SIGNALLING SYSTEM No. 5 Q.140Q.199 SPECIFICATIONS OF SIGNALLING SYSTEM No. 6 Q.250Q.309 SPECIFICATIONS OF SIGNALLING SYSTEM R1 Q.310Q.399 SPECIFICATIONS OF SIGNALLING SYSTEM R2 Q.400Q.499 DIGITAL EXCHANGES Q.500Q.599 INTERWORKING OF SIGNALLING SYSTEMS Q.

5、600Q.699 SPECIFICATIONS OF SIGNALLING SYSTEM No. 7 Q.700Q.799 Q3 INTERFACE Q.800Q.849 DIGITAL SUBSCRIBER SIGNALLING SYSTEM No. 1 Q.850Q.999 PUBLIC LAND MOBILE NETWORK Q.1000Q.1099 INTERWORKING WITH SATELLITE MOBILE SYSTEMS Q.1100Q.1199 INTELLIGENT NETWORK Q.1200Q.1699 SIGNALLING REQUIREMENTS AND PRO

6、TOCOLS FOR IMT-2000 Q.1700Q.1799 SPECIFICATIONS OF SIGNALLING RELATED TO BEARER INDEPENDENT CALL CONTROL (BICC) Q.1900Q.1999 BROADBAND ISDN Q.2000Q.2999 For further details, please refer to the list of ITU-T Recommendations. ITU-T Rec. Q.115.0 (12/2002) i ITU-T Recommendation Q.115.0 Protocols for t

7、he control of signal processing network elements and functions Summary Echo Cancellation and Voice Quality Enhancement have become a necessity not only in Circuit Switched Networks (wired and wireless) but also in Next Generation Networks. Signal processing network elements and functions are provide

8、d on a per-call basis to guarantee QoS for voice calls. This Recommendation describes the protocols to control, on a per-call basis, the signal processing functions. The protocols described in this Recommendation include TDM-based as well as IP-based protocol versions for TDM networks and IP network

9、s. Source ITU-T Recommendation Q.115.0 (2002) was prepared by ITU-T Study Group 11 (2001-2004) and approved under the WTSA Resolution 1 procedure on 29 December 2002. Keywords Automatic Level (Gain) Control, Echo cancellation, Echo control, Noise Reduction, Voice Quality Enhancement. ii ITU-T Rec. Q

10、.115.0 (12/2002) FOREWORD The International Telecommunication Union (ITU) is the United Nations specialized agency in the field of telecommunications. The ITU Telecommunication Standardization Sector (ITU-T) is a permanent organ of ITU. ITU-T is responsible for studying technical, operating and tari

11、ff 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 topics for study by the ITU-T study groups which, in turn, produce Recomme

12、ndations 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 prepared on a collaborative basis with ISO and IEC. NOTE In this Recommend

13、ation, the expression “Administration“ is used for conciseness to indicate both a telecommunication administration and a recognized operating agency. INTELLECTUAL PROPERTY RIGHTS ITU draws attention to the possibility that the practice or implementation of this Recommendation may involve the use of

14、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, ITU

15、 had not received notice of intellectual property, protected by patents, which 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. ITU 2003 All ri

16、ghts reserved. No part of this publication may be reproduced, by any means whatsoever, without the prior written permission of ITU. ITU-T Rec. Q.115.0 (12/2002) iii CONTENTS Page 1 Scope 1 2 References. 1 3 Definitions 1 4 Abbreviations and acronyms 2 5 Conceptual model . 2 6 Network scenarios 3 6.1

17、 TDM: Standalone SPNE. 3 6.2 VoIP: SPNE integrated in or external to a media gateway 4 7 Protocols . 5 7.1 TDM . 5 7.2 VoIP 5 ITU-T Rec. Q.115.0 (12/2002) 1 ITU-T Recommendation Q.115.0 Protocols for the control of signal processing network elements and functions 1 Scope Echo Control (e.g., echo can

18、cellation) and Voice Quality Enhancement (e.g., voice enhancement device) have become a necessity not only in Circuit Switched Networks (wired and wireless) but also in Next Generation Networks. Signal processing network elements and functions are provided on a per-call basis to guarantee QoS for vo

19、ice calls. This Recommendation describes the protocols to control on a per-call basis the signal processing functions. The protocols described in this Recommendation include TDM-based as well as IP-based protocol versions for TDM networks and IP networks. The signal processing function specific logi

20、c, i.e. the logic that decides on the need for a signal processing function and the number of signal processing functions to be provided for a call, is defined in ITU-T Recs Q.115.x. 2 References The following ITU-T Recommendations and other references contain provisions which, through reference in

21、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 e

22、dition 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. 1 ITU-T Recommendation Q.52

23、 (2001), Signalling between international switching centres and stand-alone echo control devices. 2 ITU-T Recommendation Q.55 (1999), Signalling between signal processing network equipment (SPNE) and international switching centres (ISC). 3 ITU-T Recommendation Q.56 (2001), Signalling between signal

24、 processing network equipment (SPNE) and international switching centers over an IP network. 4 ITU-T Recommendation H.248 (2000), Gateway Control Protocol. 5 ITU-T Recommendation G.173 (1993), Transmission planning aspects of the speech service in digital public land mobile networks. 3 Definitions T

25、his Recommendation defines the following terms: 3.1 signal processing function specific logic: A functional entity (part of call control) that decides if a signal processing function is required for this call. 3.2 signal processing function: A functional entity; examples are echo cancellation, noise

26、 reduction, automatic level (gain) control, etc. 3.3 signal processing network element: A physical entity that contains one or more signal processing functions assigned to one or more E1/T1 facilities. 2 ITU-T Rec. Q.115.0 (12/2002) 4 Abbreviations and acronyms This Recommendation uses the following

27、 abbreviations: CAS Channel associated signalling CCF Call Control Function ECD Echo Control Device ECF Echo Control Function (echo cancellation, echo suppression) E1 A transmission link operating at 2048 kbit/s, supporting 30 or 31 64 kbit/s channels. IP Internet Protocol LAN Local Area Network MG

28、Media Gateway MGC Media Gateway Controller QoS Quality of Service SPF Signal Processing Function SPFCF SPF Control Function SPFSF SPF Switching Function SPFSL SPF Specific Logic SPNE Signal Processing Network Element TDM Time Division Multiplex T1 A transmission link operating at 1544 kbit/s support

29、ing 24 speech channels. VoIP Voice over IP 5 Conceptual model For each signal processing function SPF there exists a signal processing function specific logic added to call/bearer control; see Figure 1. Any SPF is provided on a per-call basis. A master slave relation exists between the SPF switching

30、 function and the SPF control function. ITU-T Rec. Q.115.0 (12/2002) 3 rQ.115.0_F01SPFSF SPFCFCCF/BCFrFunctional planePhysical planeEXCHANGE SPNETDM:MGCMG SPNEVoIP:IP TDMSPFSLSPF may be provided in the MG or in a standalone SPNEPhysical /virtual connectionRelationship between communicating pairs of

31、functional entitiesMappingFigure 1/Q.115.0 Conceptual methodology model In the VoIP scenario where the MG controls the SPFs provided in a standalone (external) SPNE, the MG has an application protocol interworking function (H.248 SPNE package Q.52/Q.55/Q.56). 6 Network scenarios 6.1 TDM: Standalone

32、SPNE Echo suppressors and echo cancellers provided as standalone equipment are considered to be a first generation of SPNE. The protocol to control standalone echo control devices is defined in ITU-T Rec. Q.52; see Figure 2. A platform providing one or more signal processing functions is referred to

33、 as SPNE. The protocols to control standalone SPNEs are defined in ITU-T Recs Q.55 and Q.56; see Figure 2. 4 ITU-T Rec. Q.115.0 (12/2002) Q.115.0_F02SPNEECDECFQ.52E1, T1SPFsE1, T1Q.55Q.56CAS, SS7, LANIPbbE1, T1E1, T1aaa SPFSFb SPFCFEXCHANGEEXCHANGEFigure 2/Q.115.0 TDM scenarios and the control proto

34、cols 6.2 VoIP: SPNE integrated in or external to a media gateway H.248 is the media gateway protocol used between a media gateway controller and a media gateway in the decomposed architecture. The H.248 SPNE package defined in this Recommendations allows the control of signal processing functions; s

35、ee Figure 3. ITU-T Rec. Q.115.0 (12/2002) 5 Q.115.0_F03MGSPNEIPababbQ.52, Q.55MGCH.248SPNE packageE1, T1E1, T1a SPFSFb SPFCFinterworkingSPFsSPFsMGFigure 3/Q.115.0 VoIP Gateway (decomposed architecture); H.248 SPNE package (as defined in this Recommendation) is the control protocol 7 Protocols 7.1 TD

36、M The protocol to control standalone Echo Control Devices is defined in ITU-T Rec. Q.52. The protocols (protocol family, including CAS, SS7 and LAN) to control one or more SPF of a SPNE is defined in ITU-T Rec. Q.55. If a “public“ IP network is used for the transport of the control signalling, then

37、ITU-T Rec. Q.56 could be used. 7.2 VoIP This clause describes the Signal Processing Network Equipment (SPNE) package for H.248. It allows a Media Gateway Controller to control the SPFs of a SPNE equipment either integrated into or attached to a Media Gateway. The SPNE equipment may include echo canc

38、ellation (without non linear processor), automatic level control, noise reduction and frequency equalization. SPNE Control Package PackageID: spne, (-) Version: 1 Extends: TDM Package (tdmc (0x000d) Version 1 This package defines properties and events for SPNE functions controlled by or integrated i

39、nto a media gateway. Note that echo cancellers associated with media gateways are assumed to be compliant with ITU-T Rec. G.168 as indicated in ITU-T Rec. G.177. 6 ITU-T Rec. Q.115.0 (12/2002) Logic that determines which SPNE function is enabled or disabled during a call is outside the scope of this

40、 Recommendation. 7.2.1 Properties Non Linear Processing PropertyID: nlp (0x0003) Controls the non-linear processing property of an ECD on the TDM termination. Type: enumeration Possible Values: DISABLE (0x0000) ENABLE (0x0001) Defined in: LocalControlDescriptor Characteristics: Read/Write Comfort No

41、ise Injection PropertyID: cni (0x0004) This controls the comfort noise injection function of the ECD on the TDM termination. Type: enumeration Possible Values: DISABLE (0x0000) ENABLE (0x0001) Defined in: LocalControlDescriptor Characteristics: Read/Write Automatic Level Control PropertyID: alc (0x0

42、005) This provides control information for incoming automatic level control on the TDM termination. Type: enumeration Possible Values: DISABLE (0x0000) ENABLE TYPE 0 (0x0001) ENABLE TYPE 1 (0x0002) ENABLE TYPE 2 (0x0003) ENABLE TYPE 3 (0x0004) Defined in: LocalControlDescriptor Characteristics: Read

43、/Write Frequency Equalization PropertyID: fe (0x0006) This controls the frequency equalization function of a TDM termination. The characteristics of the frequency equalization type is determined and configured by manufacturer and/or carrier. Type: enumeration ITU-T Rec. Q.115.0 (12/2002) 7 Possible

44、Values: DISABLE (0x0000) ENABLE TYPE 0 (0x0001) ENABLE TYPE 1 (0x0002) ENABLE TYPE 2 (0x0003) ENABLE TYPE 3 (0x0004) Defined in: LocalControlDescriptor Characteristics: Read/Write Noise Reduction PropertyID: in-nrd (0x0007) This controls the incoming noise reduction function of a TDM termination. Th

45、e characteristics of the incoming noise reduction function type is determined and configured by manufacturer and/or carrier. Type: enumeration Possible Values: DISABLE INCOMING (0x0000) ENABLE INCOMING TYPE 0 (0x0001) ENABLE INCOMING TYPE 1 (0x0002) ENABLE INCOMING TYPE 2 (0x0003) ENABLE INCOMING TY

46、PE 3 (0x0004) Defined in: LocalControlDescriptor Characteristics: Read/Write PropertyID: out-nrd (0x0009) This controls the outgoing noise reduction function of a TDM termination. The characteristics of the outgoing noise reduction function type is determined and configured by manufacturer and/or ca

47、rrier. Type: enumeration Possible Values: DISABLE OUTGOING (0x0000) ENABLE OUTGOING TYPE 0 (0x0001) ENABLE OUTGOING TYPE 1 (0x0002) ENABLE OUTGOING TYPE 2 (0x0003) ENABLE OUTGOING TYPE 3 (0x0004) Defined in: LocalControlDescriptor Characteristics: Read/Write Events: None Signals: None Statistics: No

48、ne 8 ITU-T Rec. Q.115.0 (12/2002) 7.2.2 Procedures Echo Cancellation When a MGC determines, through Q.115.1 echo control logic, a need to provide an echo control device (ECD) on a connection, it initiates a command to the MG. The MG, upon receipt of a property with the ECD indication, enables the ec

49、ho control device associated with the specified termination if the value is ENABLE, or disables the echo control device if the value is DISABLE. Non Linear Processing Echo cancellers include a function called a non-linear processor (NLP). This operates as a smart attenuator, and eliminates residual echo during periods when only one party is speaking. In some cases the NLP function is automatically enabled when the ECD is enabled, however, in other network configurations, it is beneficial to speech quality to disable the NLP independent of