CEPT T L 03-07 E-1987 Layer 1 of the Basic User-Network Interface《基础用户网络接口第1层》.pdf

上传人:wealthynice100 文档编号:593126 上传时间:2018-12-16 格式:PDF 页数:3 大小:145.39KB
下载 相关 举报
CEPT T L 03-07 E-1987 Layer 1 of the Basic User-Network Interface《基础用户网络接口第1层》.pdf_第1页
第1页 / 共3页
CEPT T L 03-07 E-1987 Layer 1 of the Basic User-Network Interface《基础用户网络接口第1层》.pdf_第2页
第2页 / 共3页
CEPT T L 03-07 E-1987 Layer 1 of the Basic User-Network Interface《基础用户网络接口第1层》.pdf_第3页
第3页 / 共3页
亲,该文档总共3页,全部预览完了,如果喜欢就下载吧!
资源描述

1、CEPT T/L*03-07*E 87 232b414 OOObOO3 2 m Page 1 (old reference: T/TR 03-07 E) Recommendation TIL 03-07 (Copenhagen 1987) LAYER 1 OF THE BASIC USER-NETWORK INTERFACE Recommendation proposed by Working Group T/GT 12 “Transmission and Multiplexing” (TM) Text of the Recommendation revised adopted by “Tel

2、ecommunicafions” Commission : “The European Conference of Postal and Telecommunication Administrations, considering - that the definition of an interface for ISDN basic rate access, and in particular the specification of layer 1, permits the connection of subscriber terminals to the Integrated Servi

3、ces Digital Network (ISDN) to provide two B channels at 64 kbit/s and a D channel at 16 kbit/s, - that the existing CCIIIT Recommendations on the matter allow various national options, - that the CEPT Administrations favour harmonisation of telecommunication equipment and systems in order to O minim

4、ise the costs of development and manufacture of equipment, recommends that the members of the CEPT use for the basic user-network interface the specification contained in this Recom- mendation.” Note. Recommendation T/L 03-07 corresponds to CCITT Recommendation 1.430 (July 1986 edition) submitted fo

5、r approval according to the accelerated procedure, with the following modification. Edition of December 15,1987 i _ - CEPT T/L*03-07*E 7 I 2326434 0006004 4 O . T/L 03-07 E Paga 2 1. 2. 3. 4. 5. MULTIFRAMING - Delete from note 2 of Figure 3/1.430 “in every fifth frame”. - Delete Note 3 of Table 2/1.

6、430. - Figure 3/1.430 and section 5.4.2.2-bit position37, change the text from “S-the use of this bit is for further - Replace the note under 5.4.2.2 with “Note: S, FA and M are set to binary ZERO”. - Replace sections 6.3.3 and 6.3.4 by: “6.3.3 Multiframing The multiframing mechanism is intended to

7、provide extra layer 1 capacity in the TE-to-NT direction (Q chan- nel). The use of multiframing is out of the scope of this recommendation. The NT will not provide multifram- ing, therefore the FA bit in the frame NT-to-TE (see Figure 3/1.430) is set to binary ZERO. However, TES shall provide for id

8、entification of the bit positions which provide this extra capacity, designated Q-bits. The TE shall echo the binary value of the received FA bits in the corresponding FL bit position of the frame transmitted to the NT.” TEST LOOPBACKS - Appendix I/I.430 (and all references to it) is changed to Anne

9、x E. - Delete in Figure 1-1/1.430 (now Figure E-1) the optional loopbacks (A, 4, B1 and C). - Delete Tables 1-2 and 1-3/1.430. study” to “S-reserved for future standardisation”. POWER FEEDING - Replace 9.1.2 with the following text: “9.1.2 Provision of power sources and sinks The provision of Power

10、Source 1 (normal) is optional. Note: Optional in this case refers only to the responsibility of the Administration for the provision of power source 1. The capability of the provision of power source 1 shall always be available, either: - as an integral part of the NT1, and/or - physically separate

11、and connected at any point in the interface wiring. The provision of Power Source 1 (restricted) is mandatory. Note: Mandatory in this case refers only to the responsibility of the Administration for the provision of power source 1 (restricted) in a single basic access configuration. In this case of

12、 a multiple basic access to an NT2 configuration, power source 1 (restricted) shall be mandatory for at least one of the NT1 basic accesses. In some cases the provision of power source 1 (restricted) can be guaranteed only for a limited period of time. The provision of Power Source 2 is optional. Th

13、e provision of Power Source 3 is outside the scope of this Recommendation. Note: “A terminal (non-designated) that is to be portable (for example from network, country to country) cannot rely on power source 2 for its operation.” - Delete the note (and all references to it) under 9.3.1.1 (on the int

14、erim period). - Delete the note (and all references to it) under 9.5.2.1 (on the interim period). - Delete the three notes under Table 6/1.430 (two on interim periods, one on provision of power sources now covered by 9.1.2). INTERFACE CONNECTOR CONTACT ASSIGNmNTS - Replace paragraph 10/1.430 by the

15、following: “10 Interface connector assignments The interface connector and contact assignments are the subject of an IS0 standard (Draft Interna- tional Standard DIS 8877, dated November 1985). - Section 8.5.3.2-Delete “(see Table 7/1.430 for the relationship to connector pins)”. ACTIVATION/DEACTIVA

16、TION FOR NTs - Delete section 6.2.4.2. - Delete sub-paragraph heading “6.2.4.1 Activating/Deactivating NTs”. _- Edition of December 1 5, 1987 CEPT T/L*03-07*E 87 II 236434 0006005 6 1 TIL 03-07 E Page 3 6. EDITORIAL CHANGES - Section 5.1.7-Delete “(In some applications unidirectional power feeding o

17、r no power feeding at all, across - Section 5.1.7-Replace “NT” by “network side” and “TEs” by “terminal”. - Section 5.1.8-Delete “(For some applications it will be appropriate for NTs to remain in the active state - Section 5.1.9-Delete “(For some applications it will be appropriate for NTs to remai

18、n in the active state - Section 6.2.1.2.2-Change in the last sentence “within the NT” to “within the network side”. - Section 6.2.3.2-Replace “annex C” with “annex C/I.430”. - Change in the last sentence of Note 3 to Table 3/1.430 “TE” to “terminal” and “NT” to “network”. - Section 6.3.2-Delete to end of sentence from (and including) “except if the Q channel.”. - Section 8.5.3.1-Replace the rst sentence by “Pulses shall be within the mask of Figure 13/1,430 except the interface, may apply)”. all the time)”. all the time)”. of overshoot”. -l Edition of December 15, 1987 1

展开阅读全文
相关资源
猜你喜欢
相关搜索

当前位置:首页 > 标准规范 > 国际标准 > 其他

copyright@ 2008-2019 麦多课文库(www.mydoc123.com)网站版权所有
备案/许可证编号:苏ICP备17064731号-1