Page 1180 - 5G Basics - Core Network Aspects

2 Transport aspects

Table 17-6 – Cm (m=16) for supra-1.238 to sub-2.488G clients into OPU1

Nominal Bit-rate
Client signal bit rate tolerance m n CnD
(kbit/s) (ppm)

FC-200 2 125 000 100 16 8 Yes
1.5G SDI 1 485 000 10 16 TBD Yes
1.5G SDI 1 485 000/1.001 10 16 TBD Yes

Table 17-7 – Replacement signal for supra-1.238 to sub-2.488 Gbit/s clients

Client signal Replacement signal Bit-rate tolerance (ppm)

FC-200 NOS 100
1.5G SDI Generic-AIS For further study
17.7.2.1 FC-200

During a signal fail condition of the incoming FC-200 signal (e.g., in the case of a loss of input signal), this
failed incoming FC-200 signal is replaced by an NOS primitive sequence as specified in [b-INCITS 470].
NOTE – The NOS primitive sequence ordered set is defined as /K28.5/D21.2/D31.5/D5.2/.
During a signal fail condition of the incoming ODU1 signal (e.g., in the case of an ODU1-AIS, ODU1-LCK,
ODU1-OCI condition), NOS primitive sequence ordered sets as specified in [b-INCITS 470] are generated as
a replacement signal for the lost FC-200 signal.

17.7.3 Mapping CBR client signals into OPU2

Table 17-8 specifies the clients defined by this Recommendation and their GMP m, n and CnD parameter
values. Table 17-9 specifies the replacement signals for those clients.

The support for 8-bit timing information (C8D) in the OPU2 JC4/JC5/JC6 OH is required.
The support for 1-bit timing information (C1D) in the OPU2 JC4/JC5/JC6 OH is client dependent.

The OPU2 payload for this mapping consists of 4  3808 bytes. The groups of eight bytes in the OPU2
payload area are numbered from 1 to 1904. The OPU2 payload byte numbering for GMP 8-byte (64-bit)
blocks is illustrated in Figure 17-13. In row 1 of the OPU2 frame the first 8-bytes will be labelled 1, the next
8-bytes will be labelled 2, etc.
Groups of sixty-four successive bits of the client signal are mapped into a group of eight successive bytes of
the OPU2 payload area under control of the GMP data/stuff control mechanism. Each group of eight bytes
in the OPU2 payload area may either carry 64 client bits, or carry 64 stuff bits. The stuff bits are set to zero.

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