Page 1137 - 5G Basics - Core Network Aspects

Transport aspects 2

IS character # NS character #
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15

CC ICC UAPC
CC ICC UAPC
CC ICC UAPC
CC ICC UAPC
CC ICC UAPC
CC ICC UAPC

Figure 15-8  Access point identifier structure

The international segment field provides a three-character ISO 3166 geographic/political country code
(G/PCC). The country code shall be based on the three-character uppercase alphabetic ISO 3166 country
code (e.g., USA, FRA).
The national segment field consists of two subfields: the ITU carrier code (ICC) followed by a unique access
point code (UAPC).

The ITU carrier code is a code assigned to a network operator/service provider, maintained by the ITU-T
Telecommunication Standardization Bureau (TSB) as per [ITU-T M.1400]. This code shall consist of 1-6 left-
justified characters, alphabetic, or leading alphabetic with trailing numeric.
The unique access point code shall be a matter for the organization to which the country code and ITU
carrier code have been assigned, provided that uniqueness is guaranteed. This code shall consist of 6-11
characters, with trailing NUL, completing the 12-character national segment.

15.3 OTS-O description
The following OTS-O information elements are defined:

 OTS-TTI
 OTS-BDI-P
 OTS-BDI-O
 OTS-PMI

15.3.1 OTS trail trace identifier (TTI)

The OTS-TTI is defined to transport a 64-byte TTI as specified in clause 15.2 for OTSn section monitoring.
15.3.2 OTS backward defect indication – Payload (BDI-P)

For OTS section monitoring, the OTS-BDI-P signal is defined to convey in the upstream direction the OTS-P
signal fail status detected in the OTS-P termination sink function.

15.3.3 OTS backward defect indication – Overhead (BDI-O)
For OTS section monitoring, the OTS-BDI-O signal is defined to convey in the upstream direction the OTS-O
signal fail status detected in the OTS-O termination sink function.

15.3.4 OTS payload missing indication (PMI)
The OTS PMI is a signal sent downstream as an indication that upstream at the source point of the OTS-P
signal no payload is added, in order to suppress the report of the consequential loss of signal condition.

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