1、CEPT T/CS*b2-02*E U 2326434 0005242 4 Page 1 (3 TJCS62-02 E Recommendation T/CS 62-02 (Brussels 1980, modified in Vienna 1982, Montpellier 1984 and Odense 1986) INTERFACES FOR DIGITAL LOCAL AND COMBINED EXCHANGES Recommendation proposed by Working Group T/WG 11 ?Switching and Signalling? (CS) ?The E
2、uropean Conference of Postal and Telecommunications Administrations, recommends to the members of the CEPT that digital local and combined exchanges provide the interfaces as specified below.? The reader is referred to CCITT Recommendation 4.512 i, to which this Recommendation is identical, except f
3、or the addition and modifications indicated below. The section references (indicated Q) are to 4.512 i. 9 2; delete any reference to 1,544 and 6,312 kbit/s bit rates in Figure 1/Q.512 i. !-j 2.1.1.1; delete any reference to 1,544 kbit/s bit rate. 4 2.1.1.2; delete any reference to 6,312 kbit/s bit r
4、ate. 4 2.2; add at the beginning: Interfaces associated with a digital local or combined exchange are shown in Figure 1/Q.512 i. At present, there is no intention to precisely locate the actuel interfaces between the local or combined exchange and the subscriber-side network. However, it is already
5、understood that a Co-located or remote system-dependent concentrator is part of the local or combined exchange, whereas remote system independent switching units are not part of it. Q 2.2.1.2; add at the end: g) B channels will have access to the 64 kbit/s circuit switching function. Q 2.2.1.3 ; add
6、 at the end: Interface V2 should be identical to the primary multiplex described in CCITT Recommendation G.732 2, or, in the case of very large units, the secondary multiplex described in CCITT Recommendation G.744 3. Q 2.2.1.4; delete any reference to 1,544 and 6,312 kbit/s bit rates and add after
7、the first paragraph: Interface V3 should be identical to the primary multiplex described in CCITT Recommendation G.732 2, or, in the case of very large units, the secondary multiplex described in CCITT Recommendation G.744 3. Q 2.2.1.5; add after the first paragraph: Interface V4 should be identical
8、 to the primary multiplex described in CCITT Recommendation G.732 2, or to the secondary multiplex described in CCITT Recommendation G.744 131. 4 2.2.1.6; add after the first paragraph: Interface V5 should be identical to the primary multiplex described in CCITT Recommendation G.732 2, or to the sec
9、ondary multiplex described in CCITT Recommendation G.744 3. Q 2.2.3; replace the second paragraph by the following: It is recommended that such accesses are not implemented as special interfaces but as a combination of elements of the interfaces Z1 and V1. a O Q 3; add at the end of the first paragr
10、aph: The recommended values for wander do not include the phase deviation caused by plesiochronous operation with an accuracy of 1 part in 10?. 4 3.2; delete any reference to 1,544 and 6,312 kbit/s bit rates. Q 3.2; this paragraph applies to V2, V4 and V5 as well. 4 3.2; in table 1/Q.512, replace th
11、e value of fo (Le. ?12 x IO4?) by ?3 x (provisional value)?. Edition of September 15, 1986 CEPT T/CS*bZ-OZ*E. W 2326434 0005243 b M TICS 62-02 E Page 2 4 5.2; delete any reference to 1,544 and 6,312 kbit/s bit rates. 4 5.2; this paragraph applies to interfaces V2, V4 and V5 as well. REFERENCES i CCITT Recommendation 4.512. Interfaces. 2 3 CCITT Recommendation G. 732. Characteristics ofprimary PCM multiplex equipment operating at 2,048 kbitls. CCITT Recommendation G.744. Second order PCM multiplex equipment operating at 8,448 kbit/s. Edition of September 15, 1986
