OTN Fundamental-3

OTN Standardization Status:- 

Major revision to ITU-T Rec. G.709 reached consent in October 2009, including new features from Amendment 3 and subsequent agreements

Highlights encompassed in October revision

New LO ODU0 rate and format

New ODU4 rate and format (HO or LO)

New LO ODU2e rate and format, originally in G.sup43:

40/100GBASE-R, handling of parallel 66B interfaces

Transcoding for 40GBASE-R into OPU3 and FC-1200 into OPU2e

OTU3/OTU4 striping over parallel lanes allow use of Ethernet modules for IrDI

New delay measurement capability added

OTN Hierarchy:

ODU0 Definition:

Smallest contained defined in G.709 (OTN Standard)
1.25G container size (specifically 1.244160 Gbit/s20ppm)
Established in October 2009 for transport of 1000BASE-X (Gigabit Ethernet)
Sized to fit existing OTN hierarchy
2 into ODU1
8 into ODU2
32 into ODU3
80 into ODU4
ODU0 can carry:
1000Base-X (1GbE)
STM-1
STM-4
FC-100
No OTU0 physical layer
Only a lower order wrapper for 1000BASE X mapped into standardized physical layers OTU1 and above

ODU1 Definition

Original tier of the hierarchy to transport 2.5G signals
ODU1 = 2.498775Gbit/s
OTU1 = 2.666057Gbit/s
Can be used as a higher order ODU to carry lower order ODU0s
Divided into 21.25G tributary slots:
ODU0 maps into 1 tributary slot
OPU1 can carry:
STS-48
STM-16
FC-200

ODU2 Definition:

Original tier of the hierarchy to transport 10G signals
ODU2 = 10.037273Gbit/s
OTU2 = 10.709224Gbit/s
Can be used as a higher order ODU to carry lower order ODUs
Divided into 42.5G or 81.25G tributary slots:
ODU0 maps into 1 tributary slot
ODU1 maps into 1 2.5G or 2 1.25G tributary slot(s)
ODUflex maps into 1-8 1.25G tributary slots
OPU2 can carry:
STS-192
STM-64

ODU3 Definition:

Original tier of the hierarchy to transport 40G signals
ODU3 = 40.319218Gbit/s
OTU3 = 43.018410Gbit/s
Can be used as a higher order ODU to carry lower order ODUs

Divided into 162.5G or 321.25G tributary slots:
ODU0 maps into 1 tributary slot
ODU1 maps into 1 2.5G or 2 1.25G tributary slot(s)
ODU2 maps into 4 2.5G or 8 1.25G tributary slot(s)
ODU2e maps into 9 1.25G tributary slots
ODUflex maps into 1-32 1.25G tributary slots.

OPU3 can carry:
STS-768
STM-256
Transcoded 40GBase-R.

ODU4 Definition:

New tier of the hierarchy (Oct-09)
ODU4 = 104.794445Gbit/s
OTU4 = 111.809973Gbit/s
Can be used as a higher order ODU to carry lower order ODUs

Divided into 801.25G tributary slots:
ODU0 maps into 1 tributary slot
ODU1 maps into 2 tributary slots
ODU2 or ODU2e maps into 8 tributary slots
ODU3 maps into 32 tributary slots
ODUflex maps into 1-80 tributary slots

OPU4 can carry: 100GBase-R