Page 1116 - 5G Basics - Core Network Aspects

2 Transport aspects

NOTE 1 – The ODTUGk is a logical construct and is not defined further. ODTUjk and ODTUk.ts signals are directly time-
division multiplexed into the tributary slots of an OPUk.
A mixture of p (p  10n) ODU0, q (q 10n) ODU1, r (r  10n) ODU2, s (s  10n) ODU2e, t (t int(10n/4))
ODU3, u (u  n) ODU4 and v (v  10n) ODUflex signals can be multiplexed into an ODTUGCn (PT=22) using
time-division multiplexing. The ODTUGCn (PT=22) is mapped into the OPUCn.
NOTE 2 – The ODTUGk and ODTUGCn are logical constructs and are not defined further. ODTUjk and ODTUk.ts signals
are directly time-division multiplexed into the tributary slots of an OPUk. ODTUCn.ts signals are directly time-division
multiplexed into the tributary slots of an OPUCn.
NOTE 3 – Implementations should support the multiplexing of up to 10n ODUk (k=0,1,2,2e,3,4,flex) signals into an
OPUCn. Support for the multiplexing of up to 20n ODUk (k=0,1,flex) signals into the OPUCn is not required.

Table 7-10 – Overview of ODUj into OPUk and ODUk into OPUCn mapping types

5G tributary slots 2.5G tributary slots 1.25G tributary slots
OPUCn OPU2 OPU3 OPU1 OPU2 OPU3 OPU4
(PT=22) (PT=20) (PT=20) (PT=20) (PT=21) (PT=21) (PT=21)
ODU0 GMP - Note – – AMP GMP GMP GMP
ODU1 GMP - Note AMP AMP – AMP AMP GMP
ODU2 GMP – AMP – – AMP GMP
ODU2e GMP – – – – GMP GMP

ODU3 GMP – – – – – GMP
ODU4 GMP – – – – – –
ODUflex GMP – – – GMP GMP GMP
NOTE – Mapping ODU0 and ODU1 into a 5G tributary slot of the OPUCn does not fully occupy the tributary slot’s bandwidth.

Figures 7-2, 7-3 and 7-4 show how various signals are multiplexed using the ODTUG1/2/3 (PT=20)
multiplexing elements. Figure 7-2 presents the multiplexing of four ODU1 signals into the OPU2 signal via
the ODTUG2 (PT=20). An ODU1 signal is extended with a frame alignment overhead and asynchronously
mapped into the optical data tributary unit 1 into 2 (ODTU12) using the AMP justification overhead (JOH).
The four ODTU12 signals are time-division multiplexed into the optical data tributary unit group 2
(ODTUG2) with payload type 20, after which this signal is mapped into the OPU2.

ODU1 ODU1 payload
OH ODU1

ODTU12 ODU1 ODTU12
JOH

ODTU12 .... ODTU12 ODU1 ...... ODU1 ODTUG2
JOH JOH

ODTUG2

OPU2 OPU2 payload OPU2
OH

ODU2 ODU2 payload
OH ODU2
G.709-Y.1331(12)_F7-2

Figure 7-2  ODU1 into ODU2 multiplexing method via ODTUG2 (PT=20)

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