1. Swapped Fig 3a and 3b per Francois and Tailey.
2. All TIA-968-A-1 related changes.
3. Changed DEO pad from 3 to 6 dB.
4. Added support for MTAs and IADS in conjunction with the revision of T1.508.
This contribution has been prepared by Nortel Networks to assist the TIA TR-41 Engineering Committee or one of its sub-elements as noted above. It is offered as a basis for discussion and is not to be construed as a binding proposal on Nortel Networks. Nortel Networks specifically reserves the right to amend or modify the material contained herein, and nothing herein shall be construed as conferring or offering licenses or rights with respect to any intellectual property of Nortel Networks other than as provided in the copyright statement above.
The individual preparing this contribution is unaware of any patents or published pending patent applications, the use of which may be essential to the practice of all or part of this contribution when incorporated into a TIA Publication.
1 Introduction 1
1.1 General 1
1.2 Purpose 1
1.3 Categories of Performance Criteria 1
2 Scope 2
2.1 Compliance Reference Point 2
2.2 Compliance Interpretation 2
2.3 Regulatory Issues 2
2.4 Changes Relative to TIA-912 2
3 References 4
4 Definitions, Abbreviations and Acronyms 5
4.1 Voice Gateway Definition 5
4.2 Insertion Loss Definition 5
4.3 Sound Pressure Level Definition 5
4.4 Loudness Rating Definitions 5
4.5 Port Definitions 6
4.6 Port Descriptions 6
4.7 Abbreviations and Acronyms 9
5 Preamble 10
5.1 General 10
5.2 Reference Impedance 10
6 Loss and Level Plans 11
6.1 Introduction 11
6.2 Port-to-Port Loss Allocation 11
6.3 Digital Padding 12
6.4 Voice Gateway Loss Plan Assumptions 12
6.5 Full-Channel Loss and Level Plan 13
6.6 Half-Channel Loss and Level Plan 17
7 Loss Parameters 21
7.1 Frequency Response 21
7.2 Tracking Error and Overload Compression 21
8 Echo Control and Return Loss 24
8.1 Hybrid Balance Requirements 24
8.2 Input Impedance Requirements 25
9 Noise and Distortion Impairments 27
9.1 Idle-Channel Noise 27
9.2 Longitudinal Balance 28
9.3 Crosstalk 30
9.4 Quantization Distortion 30
9.5 Single-Frequency Distortion 30
10 Other Impairments 31
10.1 Intermodulation Distortion 31
10.2 Envelope Delay 32
10.3 Impulse Noise 34
10.4 Jitter 34
10.5 Gain Hit 34
10.6 Phase Hit 34
10.7 Dropout 34
10.8 Peak-to-Average Power Ratio 34
11 Signal Levels 35
Annex A (informative) - Measurement Guidelines 36
A.1 Gain Ripples in the Measurement Path 36
A.2 Transmission Level Translation 36
A.3 Dial-up Port for Trunk Testing 36
A.4 Digital Test Port Availability 36
A.5 Hybrid Balance 37
A.6 Input Impedance 37
A.7 Idle Channel Noise 41
A.8 Longitudinal Balance 42
A.8.1 Longitudinal to Metallic Balance 42
A.8.2 Metallic to Longitudinal (Transverse) Balance 42
A.8.2.1 Transverse Balance Test (Analog) 43
A.8.2.2 Transverse Balance Test (Digital) 46
A.9. Crosstalk Coupling Loss 47
Annex B (informative) - Telephony Loss Level Planning Overview 49
B.1 Introduction 49
B.2 Send and Receive Levels 49
B.2.1 Telephone Equipment Loudness Ratings 50
B.2.2 Overall Loudness Ratings 50
B.2.3 Optimum Overall Loudness Ratings 51
B.2.4 Network Interface Equivalent Loudness Ratings 52
B.3 Port-to-Port Loss Allocation 52
B.4 DTMF Overload on Analog Trunks 53
B.5 Open Loop Loss and Network Stability 54
B.6 Reference Levels 55
B.6.1 Zero-Level Point 55
B.6.2 0 dBm0 Definition 55
B.6.3 Digital Milliwatt 55
B.6.4 Transmission Level Translation 56
Annex C (informative) - Loss Definitions 57
C.1 Echo Return Loss (ERL) 57
C.2 Return Loss (RL) 58
C.3 Transhybrid Loss (THL) 58
Annex D (informative) - Pan-European Loss and Level Plans 59
D.1 Half-Channel Loss and Level Plan 59
D.2 Full-Channel Loss and Level Plan 60
Annex E (informative) - IP Transmission Impairments 61
E.1 Delay 61
E.2 Packet Loss 61
E.3 Voice Gateways and Network Performance 61
E.4 Voice Quality of Service 62
The TR-41.4 IP Telephony Gateways Subcommittee acknowledges the contribution made by the following individuals in the development of this standard.
Suggestions for improvement of this standard are welcome. They should be sent to: