Band

Blu

e B

an

d

L2

192000 20 1561.42

192100 21 1560.61

192200 22 1559.79

192300 23 1558.98

192400 24 Unused

192500 25 1557.36

192600 26 1556.55

192700 27 1555.75

192800 28 1554.94

192900 29 Unused

L1

193000 30 1553.33

193100 31 1552.52

193200 32 1551.72

193300 33 1550.92

193400 34 Unused

193500 35 1549.32

193600 36 1548.51

193700 37 1547.72

193800 38 1546.92

193900 39 Unused

194000 40 Unused

194100 41 Unused

Re

d B

an

d

S1

194200 42 1543.73

194300 43 1542.94

194400 44 1542.14

194500 45 1541.35

194600 46 Unused

194700 47 1539.77

194800 48 1538.98

194900 49 1538.19

195000 50 1537.4

195100 51 Unused

S2

195200 52 1535.82

195300 53 1535.04

195400 54 1534.25

195500 55 1533.47

195600 56 Unused

195700 57 1531.9

195800 58 1531.12

Central Frequency (GHz)

Channel Number

Central Wavelength(nm); Wavelength Deviation:+/- 12 nm (EOL)

Re

d B

an

d

S2

195900 59 1530.33

196000 60 1529.55

ITU GridDWDM Lambda Information

191.7 17 1563.86 193.2 32 1551.72 194.7 47 1539.77191.8 18 1563.05 193.3 33 1550.92 194.8 48 1538.98191.9 19 1562.23 193.4 34 1550.12 194.9 49 1538.19192 20 1561.42 193.5 35 1549.32 195 50 1537.4

192.1 21 1560.61 193.6 36 1548.51 195.1 51 1536.61192.2 22 1559.79 193.7 37 1547.72 195.2 52 1535.82192.3 23 1558.98 193.8 38 1546.92 195.3 53 1535.04192.4 24 1558.17 193.9 39 1546.12 195.4 54 1535.25192.5 25 1557.36 194 40 1545.32 195.5 55 1533.47192.6 26 1556.56 194.1 41 1544.53 195.6 56 1532.68192.7 27 1555.75 194.2 42 1543.73 195.7 57 1531.9192.8 28 1554.94 194.3 43 1542.94 195.8 58 1531.12192.9 29 1554.13 194.4 44 1542.14 195.9 59 1530.33193 30 1553.33 194.5 45 1541.35 196 60 1529.55

193.1 31 1552.52 194.6 46 1540.56 196.1 61 1528.77

While this grid defines a standard, users are free to use the wavelengths in arbitrary ways and to choosefrom any part of the spectrum. In addition, manufacturers can deviate from the grid by extending theupper and lower bounds or by spacing the wavelengths more closely, typically at 50 GHz, to double thenumber of channels. The closer the spacing, the more channel crosstalk results. In addition, the impactof some fiber nonlinearities, such as FWM, increases. Spacing at 50 GHz also limits the maximum datarate per wavelength to 10 Gbps. The implications of the flexibility in implementation are twofold: Thereis no guarantee of compatibility between two end systems from different vendors, and there exists adesign trade-off in the spacing of wavelengths between number of channels and maximum bit rate.

Frequency (THZ)

Channel Number

Wavelength (nm)

Frequency (THZ)

Channel Number

Wavelength (nm)

Frequency (THZ)

Channel Number

Wavelength (nm)