Table of Contents - G.798.4 (02/2026) - Characteristics of optical transport network hierarchy equipment functional blocks - FlexO

1	Scope
2	References
3	Definitions
	3.1	Terms defined elsewhere
4	Abbreviations and acronyms
5	Conventions
6	Supervision
	6.1	Alarm reporting control
	6.2	Defects
	6.3	Consequent actions
	6.4	Defect correlations
	6.5	Performance filters
7	Information flow across reference points
8	Generic processes
	8.1	Alignment processes
	8.2	Signal quality supervision
	8.3	Forward error correction (FEC) processing
	8.4	Trail trace identifier (TTI) processing
	8.5	Payload structure
	8.6	Status information (STAT) acceptance process
	8.7	Maintenance signal generation and detection
	8.8	Generic layer fault processing
	8.9	FlexO instance signals interleaving processes
	8.10	FlexOsec processing for encryption and authentication of fixed-length FlexO frame structures
9	Media layer to client layer adaptation functions
	9.1	OTSi to FlexO-x adaptation function (M-AI/FlexO-x_A)
	9.2	OTSiG to FlexO-x adaptation function (OTSiG/FlexO-x_A)
	9.3	OTSi to FlexOxR adaptation function (M-AI/FlexOxR_A)
	9.4	OTSiG to FlexOxR adaptation function (M-AI/FlexOxR_A)
10	FlexOxR (layer) functions
	10.1	Connection functions
	10.2	Termination functions
	10.3	Adaptation functions
11	FlexOnM (layer) functions
	11.1	Connection functions
	11.2	Termination functions
	Page
	11.3	Adaptation functions
	11.4	Layer processor functions
Annex A – FlexO functions
	A.1	Connection functions
	A.2	Termination functions
	A.3	Adaptation functions
	A.4	Compound functions
Annex B – Generic FlexO supervision and processes
	B.1	Supervision
	B.2	Generic processes
Appendix I – Examples of compound adaptation functions