When the Layer 1 Synchronised option is used (i.e. PDH/SDH/SONET links), the following requirements shall be met:
Layer 1 reference configuration shall be according to ITU-T Rec. I.432.1
[6].
The physical layer is divided into:
-
Physical Media Dependent (PMD) sublayer;
-
Transmission Convergence (TC) sublayer defined according to ITU-T Rec. I.432.1 [6].
The PMD shall comply with at least one of the following standards:
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ETSI STM-4 (622 Mb/s) interface according to ITU-T Rec. I.432.2 [1] with optical S-4.1 interface according to ITU-T Rec. G.957 [5].
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SONET STS-12c (622 Mb/s) interface according to ANSI, T1.105-1995 with optical multimode.
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SONET STS-3c (155 Mb/s) interface according to ANSI, T1.105-1995 with optical multimode.
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ETSI STM-1 (155 Mb/s) interface according to ITU-T Rec. I.432.2 [1] with electrical interface (CMI) to ITU-T Rec. G.703 [3].
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ETSI STM-1 (155 Mb/s) interface according to ITU-T Rec. I.432.2 [1] with optical S-1.1 interface according to ITU-T Rec. G.957 [5].
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ITU STS-1 (51 Mb/s) interface according to ANSI, T1.105-1995 with electrical interface.
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ITU STM-0 (51 Mb/s) interface according to ETSI/TTC with electrical interface.
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ITU STM-0 (51 Mb/s) interface according to ETSI/TTC with optical S-1.1 interface according to ITU-T Rec. G.957 [5].
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J2, 6.3 Mb/s interface according to Japanese standard JT-G.703 (ITU-T Rec. G.703 [3]) and JT-G.704 (ITU-T Rec. G.704 [4]) (75 Ohm).
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E2, 8Mb/s according to ETSI/ITU G.703 (ITU-T Rec. G.703 [3]) and G.704 (ITU-T Rec. G.704 [4]) (75 Ohm).
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E3, 34 Mb/s interface according to ETSI/ITU G.751 (ITU-T Rec. G.751 [15]) (75 Ohm).
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T3, 45 Mb/s interface according to ANSI/ITU G.703 (ITU-T Rec. G.703 [3]) and G.704 (ITU-T Rec. G.704 [4]) (75 Ohm).
-
E1, 2Mb/s interface balanced 120 Ohm symmetrical according to ETS 300 420 (Standard ECMA-226 [18]), ITU-T Rec. G.704 [4] and TBR 013 (ITU-T Rec. G.703 [3]), and AF-PHY-0064.000 [13].
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E1, 2Mb/s according to ITU-T Rec. G.703 [3] and ITU-T Rec. G.704 [4] (75 Ohm), and AF-PHY-0064.000 [13].
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J1, 1.5 Mb/s interface according to JT-I.431-a (ITU-T Rec. I.431 [19]) (100 Ohm).
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J1, 1.5 Mb/s interface according to JT-G.703 (ITU-T Rec. G.703 [3]) and JT-G.704 (ITU-T Rec. G.704 [4]) (110 Ohm).
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T1, 1.5 Mb/s interface according to AF-PHY-0016.000 [12] and ITU-T Rec. G.703 [3] and ITU-T Rec. G.704 [4] (100 Ohm).
Services provided to the upper layer shall be independent from the used underlying technology.
The support of intervening transport networks - like PDH or SDH terrestrial links, Point-to-point or Point-to-Multipoint radio links - shall not be prevented.
When using E1, T1, or J1, it shall be possible to use inverse multiplexing of ATM (IMA) (ATM Forum AF-PHY-0086.001
[14]) within suitable subsets of the physical ports on the respective Exchange Termination (ET).
The jitter and wander performance requirements on the interface shall be in accordance with network limits for output wander at traffic interfaces of either Reference ITU-T Rec. G.823
[7], ITU-T Rec. G.824
[8] or network limits for the maximum output jitter and wander at any hierarchical interface of Reference ITU-T Rec. G.825
[9], whichever is applicable.
The synchronisation reference extracted from the Iu may be used as UTRAN synchronisation reference. A general recommendation is to supply a traceable synchronisation reference according to reference ITU-T Rec. G.811
[16].
Transmission quality control shall be provided according to ITU-T Rec. G.826
[10].
When Layer 1 unsynchronised option is used, the following requirements shall be met:
The support of any suitable physical layer - like Ethernet L1 or other suitable point-to-point or point-to-multipoint techniques - shall not be prevented.