1、INTERNATIONAL TELECOMMUNICATION UNION ITU-T TELECOMMUNICATION STANDARDIZATION SECTOR OF ITU INTEGRATED SERVICES DIGITAL NETWORK (ISDN) ISDN USER-NETWORK INTERFACES 1.430 (1 1/95) BASIC USER-NETWORK INTERFACE - LAYER 1 SPECIFICATION ITU-T Recommendation 1.430 (Previously “CCIlT Recommendation”) ITU-T
2、 RECMNxI.430 95 = 4862593 Ob35348 411 w FOREWORD The ITU-T (Telecommunication Standardization Sector) is a permanent organ of the International Telecommunication Union (ITU). The -T is responsible for studying technical, operating and tariff questions and issuing Recommen- dations on them with a vie
3、w to standardizing telecommunications on a worldwide basis. The World Telecommunication Standardization Conference (WTSC), which meets every four years, establishes the topics for study by the -T Study Groups which, in their turn, produce Recommendations on these topics. The approval of Recommendati
4、ons by the Members of the ITU-T is covered by the procedure laid down in WTSC Resolution No. 1 (Helsinki, March 1-12, 1993). ITU-T Recommendation 1.430 was revised by IT-T Study Group 13 (1993-1996) and was approved under the WTSC Resolution No. 1 procedure on the 2nd of November 1995. NOTE In this
5、Recommendation, the expression “Administration” is used for conciseness to indicate both a telecommunication administration and a recognized operating agency. O ITU 1996 All rights reserved. No part of this publication may be reproduced or utilized in any form or by any means, electronic or mechanic
6、al, including photocopying and microfilm, without permission in writing from the ITU. . 1 2 5 6 CONTENTS General . Service characteristics 2.1 Services required from the physical medium 2.2 Service provided to layer 2 . 2.2.1 Transmission capability 2.2.2 Activatioddeactivation . 2.2.3 D-channel acc
7、ess . 2.2.4 Maintenance 2.2.5 Status indication 2.3 Primitives between layer 1 and the other entities . Modes of operation 3.1 Point-to-point operation 3.2 Point-to-multipoint operation . Types of wiring configuration 4.1 Point-to-point configuration . 4.2 Point-to-multipoint configuration . 4.3 Wir
8、ing polarity integrity . 4.4 Location of the interfaces . 4.5 NT and TE associated wiring Functional characteristics . 5.1 5.2 5.3 5.4 5.5 5.6 Interface functions 5.1.1 B-channel 5.1.2 Bit timing 5.1.3 Octet timing 5.1.5 D-channel 5.1.6 D-channel access procedure 5.1.7 Power feeding . 5.1.8 Deactiva
9、tion 5.1.9 Activation Interchange circuits . Connecteddisconnected indication 5.3.1 TES powered across the interface 5.3.2 TES not powered across the interface . 5.3.3 Indication of connection status . Frame structure . 5.4.1 Bit rate 5.4.2 Line code 5.1.4 Frame alignment . Binary organization of th
10、e frame Timing considerations Interface procedures . 6.1 D-channel access procedure . 6.1.1 Interframe (layer 2) time fill . 6.1.2 D-echo channel . 6.1.3 D-channel monitoring . 6.1.4 Priority mechanism . 6.1.5 Collision detection 6.1.6 Priority system Recommendation 1.430 (11/95) Page 1 1 1 1 1 2 2
11、2 2 2 3 3 3 3 3 3 3 3 4 4 4 4 5 5 5 5 5 5 5 5 5 5 6 6 6 6 6 6 8 9 9 9 9 9 9 9 10 10 1 48b32591 Ob15350 0T Page 6.2 Activatioddeactivation . 6.2.1 Definitions . 6.2.2 Signals 6.2.3 Activatioddeactivation procedure for TES . 6.2.4 Activatioddeactivation for NTs 6.2.5 Timer values 6.2.6 Activation time
12、s 6.2.7 Deactivation times . 6.3 Frame alignment procedures . 6.3.1 Frame alignment procedure in the direction NT to TE . 6.3.2 Frame alignment in the direction TE to NT 6.3.3 Multiframing . 6.3.4 S-channel structuring algorithm Idle channel code on the B-channels 6.4 10 10 12 13 15 15 17 17 17 17 1
13、8 18 20 20 7 Layer 1 maintenance 20 Provision for operational and maintenace functions between terminal and NT1 . 20 7.1.1 Introduction . 21 7.1.2 Test loopbacks 21 7.1.3 Codes. message durations. and detection algorithms for a . Q-channel and SC1-subchannel 21 7.1.4 Code priorities for Q-channel an
14、d SC1-subchannel 21 7.1.5 TE-to-NT direction messages (Q bits) 21 7.1.6 NT-to-TE direction messages (SC1 bits) 23 7.1.7 B-channel loopback indications (LBlI, LB2I. LB1/21) 24 7.1.8 Loss-of-received-signal indication (LRS) . 24 7.1 7.1.9 Disruptive NT Operation Indication (DOI) 24 8 Electrical charac
15、teristics . 8.1 Bit rate 8.1.1 Nominal rate 8.1.2 Tolerance . Jitter and bit-phase relationship between TE input and output . 8.2.1 Test configurations 8.2.2 Timing extraction jitter . Total phase deviation input to output 8.2 8.2.3 8.3 NT jitter characteristics . 8.4 Termination of the line . 8.5 T
16、ransmitter output characteristics . 8.5.1 Transmitter output impedance 8.5.2 Test load impedance milse shape and amplitude (binary ZERO) . 8.5.4 milse unbalance . 8.5.6 Unbalance about earth . 8.5.3 8.5.5 Voltage on other test loads (TE only) . 8.6 Receiver input characteristics . 8.6.1 Receiver inp
17、ut impedance . 8.6.2 Receiver sensitivity - Noise and distortion immunity 8.6.3 NT receiver input delay characteristics . 8.6.4 Unbalance about earth . 8.7 8.8 Interconnecting media characteristics . 8.9 Standard ISDN basic access TE cord . Isolation from external voltages . : . 8.10 Longitudinal ou
18、tput voltage 8.11 Electromagnetic compatibility (EMC) 25 25 25 25 25 25 27 27 28 28 28 28 29 29 31 31 31 31 31 33 36 37 37 38 38 38 38 ii Recommendation 1.430 (lV95) ITU-T RECMNtI.430 95 4862573 Ob35353 Tob = 9 Power feeding . 9.1.1 Functions specified at the access leads . 9.1.2 Provision of power
19、sources and sinks . 9.1.3 Power feeding voltage . Power available from NT 9.2.1 Power source 1 normal and restricted mode . 9.2.2 Voltage NT from power source 1 . 9.2.3 Voltage of power source 2 9.2.4 Short circuit protection . Power available at TE . 9.3.2 9.3.3 9.1 Reference configuration 9.2 9.3
20、9.3.1 Power consumption unit . Power source 1 - Phantom powering Power source 2 - Optional third pair . 9.4 PSI current transient . 9.5 TE power consumption . 9.5.1 Power source 1 9.5.2 Power source 2 9.6 Galvanic isolation . 9.7 Limitations on power source and sink during transient condition . 9.7.
21、1 Currentltime limitations for “Es . 9.7.2 Power source switchover time (PSI or PS2) 9.7.3 Other TE requirements 9.7.4 Other power source requirements . PS1 direct current unbalance 9.8.2 9.9.1 Power available from an APS . 9.9.2 APS switch-on time 9.9.3 APS switch-off time 9.9.4 APS power consumpti
22、on when off . 9.9.5 Dynamic behaviour of APS 9.10.1 PS1 restricted mode back-off 9.10.2 PS1 restricted mode power-up 9.10.3 NTl power consumption from APS normal mode . 9.8 9.8.1 TE requirements NT requirements . : . Additional requirements for an auxiliary power supply (APS) 9.9 9.10 Additional req
23、uirements for NT1 restricted mode source for compatibility with an APS . Page 39 39 41 41 41 41 41 42 42 42 42 42 43 43 43 43 43 45 45 46 46 49 49 50 52 53 54 54 54 55 55 55 55 55 55 55 55 10 Interface connector contact assignments 56 Annex A . Wiring configurations and round trip delay consideratio
24、ns used as a basis for electrical Characteristics . 56 A.l Introduction 56 A.2 Wiring configurations . 57 A.2.1 Point-to-multipoint 57 A.2.2 Point-to-point (Figure A.3) . 58 60 Annex B - SDL representation of a possible implementation of the D-channel access Annex C . 61 Annex D . Test configuration
25、 . 72 Appendix I . Testing methods 73 1.1 Introduction 73 I 1.1 Basic assumptions for test 73 1.2 D-channel tests 73 1.2.1 D-echo channel . 73 1.2.2 D-echo channel response 73 . . Recommendation 1.430 (11/95) iii ITU-T RECflMtI.430 95 W 4862591 Ob15352 942 = 1.3 1.4 1.5 1.6 1.7 1.8 1.9 Interface pro
26、cedure tests . 1.3.1 ActivationDeactivation procedures 1.3.2 Timer for activatioddeactivation TE jitter characteristics . TE jitter measurement characteristics . TE output phase offset 1.4.1 1.4.2 Pulse shape and amplitude 1.5.1 Pulse shape 1.5.2 milse unbalance test Terminal power feeding dynamic r
27、equirements . 1.6.1 Test of TE start-up 1.6.2 Current transient 1.6.3 Currenflime limitations for TES 1.6.4 1.6.5 1.6.6 Protection against short-term interruptions . TE Behaviour at switchover Behaviour at low input voltage . Power source dynamic requirements . 1.7.1 Power source type . Restricted m
28、ode requirements for type a) sources only Normal mode requirements for type a) sources only Restricted mode requirements for both type a) and type b) sources . Normal mode requirements for both type a) and type b) sources . PSI restricted mode power-up APS Dynamic requirements 1.8.1 APS Switch-on ti
29、me 1.8.2 APS switch-off time Testing for current unbaiance . 1.7.2 1.7.3 1.7.4 1.7.5 1.7.6 Power source switchover 1.7.7 Appendix II . Guidelines for implementation . II . 1 n.2 iv Power feeding . II.1.1 Introduction . 11.1.2 Power consumption . II . 1.3 II.1.4 Power source ripple . II.1.5 Dynamic b
30、ehaviour of power sources and sinks . iI.1.6 Power source design for improved performance II.1.7 TE design for improved performance . Information on activation and deactivation tables iI.2.1 Operation of Timer T3 II.2.2 Connection status General assumptions . Recommendation 1.430 (11/95) Page 74 74
31、77 77 77 77 77 77 78 78 78 80 80 81 81 81 82 82 82 82 83 84 85 85 86 86 87 88 90 90 90 91 91 92 92 94 95 96 98 98 SUMMARY This Recommendation defines the layer 1 Characteristics of the user-network interface at S- and T-reference points for basic rate ISDN as defined in Recommendation 1.412. It defi
32、nes service characteristics, mode of operation, wiring configuration and functional characteristics. The transmission characteristics, frame structure, line code and activation procedure at the interface are specified to facilitate the access of user equipment to the 2B- + D-channel at a bit rate of
33、 192 kbit/s. The specification of the electrical transmission characteristics and the power feeding over the interface shall ensure portability of terminal equipment for basic rate ISDN. V Recommendation 1.430 (l95) ITU-T RECMN*I.430 95 48b2593 Ob35354 735 m ITU-T RECMN*I.430 95 W 48b2571 Ob15355 b5
34、1 = TE1 Recommendation 1.430 s- T NT2 NT1 1 1 1 Transmission line BASIC USER-NETWORK INTERFACE - LAYER 1 SPECIFICATION (Malaga-Torremolinos, 1984; amended at Melbourne, 1988 and at Helsinki 1993; revised in 1995) 1 General This Recommendation defines the layer 1 characteristics of the user-network i
35、nterface to be applied at the S- or T-reference points for the basic interface structure defined in Recommendation 1.4 12. The reference configuration for the interface is defined in Recommendation 1.41 1 and is reproduced in Figure 1. U U I t+l TA - T1820540-93/dOl U U + Referemepoint 0 Functional
36、group FIGURE 1A.430 Reference configurations for the ISDN wer-network interfaces In this Recommendation, the term “NT” is used to indicate network terminating layer 1 aspects of NT1 and NT2 functional groups, and the term “TE” is used to indicate terminal terminating layer 1 aspects of TE1, TA and N
37、T2 functional groups, unless otherwise indicated. However, in 6.2 only, the terms “NT” and TE have the following meaning: the term “NT is used to indicate the layer 1 network side of the basic access interface; the term “TE” is used to indicate the layer 1 terminal side of the basic access interface
38、. Terms used in this Recommendation, together with their definitions, are contained in Recommendation I. 1 12. 2 Service characteristics 2.1 Services required from the physical medium Layer 1 of this interface requires a balanced metallic transmission medium, for each direction of transmission, capa
39、ble of supporting 192 kbit/s. 2.2 Layer 1 provides the following services to layer 2 and the management entity. Service provided to layer 2 2.2.1 Transmission capability Layer 1 provides the transmission capability, by means of appropriately encoded bit streams, for the B- and D-channels and the rel
40、ated timing and synchronization functions. Recommendation 1.430 (1Y95) 1 2.2.2 Activatioddeactivation PH-DATA PH-ACTIVATE PH-DEACTIVATE Layer 1 provides the signalling capability and the necessary procedures to enable customer TES and/or NTs to be deactivated when required and reactivated when requi
41、red. The activation and deactivation procedures are defined in 6.2. X X X X Layer 2 peer-to-peer message X X - X - - (Note 1) (Note 2) - - 2.2.3 D-channel access MPH-ERROR MPH-ACTIVATE MPH-DEACTIVATE MPH-INFORM AVON Layer 1 provides the signalling capability and the necessary procedures to allow TES
42、 to gain access to the common resource of the D-channel in an orderly fashion while meeting the performance requirements of the D-channel signalling system. These D-channel access control procedures are defined in 6.1. - X - X Type of error or recovery from a previously reported error - - X - X X -
43、- - X - X Connecteddisconnected 2.2.4 Maintenance Layer 1 provides the signalling capability, procedures and necessary functions at layer 1 to enable maintenance functions to be performed. 2.2.5- Status indication Layer 1 provides an indication to the higher layers of the status of layer 1. 2.3 Prim
44、itives between layer 1 and the other entities Primitives represent, in an abstract way, the logical exchange of information and control between layer 1 and other entities. They neither specify nor constrain the implementation of entities or interfaces. The primitives to be passed across the layer 1/
45、2 boundary or to the management entity and parameter values associated with these primitives are defined and summarized in Table 1. For description of the syntax and use of the primitives, refer to Recommendation X.211 and relevant detailed descriptions in clause 6. TABLE 1A.430 Primitives associate
46、d with layer 1 Generic I Specific name I Parameter I Priority Message I Request 1 Indication I indicator I unit I Message unit content I Ll+L2 1 2 Recommendation 1.430 (11195) 3 Modes of operation Both point-to-point and point-to-multipoint modes of operation, as described below, are intended to be
47、accommodated by the layer 1 characteristics of the user-network interface. In this Recommendation, the modes of operation apply only to the layer 1 procedural characteristics of the interface and do not imply any constraints on modes of operation at higher layers. 3.1 Point-to-point operation Point-
48、to-point operation at layer 1 implies that only one source (transmitter) and one sink (receiver) are active at any one time in each direction of transmission at an S- or T-reference point. (Such operation is independent of the number of interfaces which may be provided on a particular wiring configu
49、ration - see clause 4.) 3.2 Point-to-multipoint operation Point-to-multipoint operation at layer 1 allows more than one TE (source and sink pair) to be simultaneously active at an S- or T-reference point. (The multipoint mode of operation may be accommodated, as discussed in clause4, with point-to-point or point-to-multipoint wiring configurations.) 4 Types of wiring configuration The electrical characteristics of the user-network interface are determined on the basis of certain assumptions about the various wiring configurations which may exist in the user premises.
