All About DWDM

DWDM has some significant advantages over CWDM. When your project consists of a longer distance than 10 kilometers and you want to future proof or you’re already planning to use more than 18 times 10 Gigabit; DWDM is your preferred technique. If you have any doubts, feel free to contact us for additional information.

The International Telecommunication Unit Telecommunication Standardization Sector (ITU-T) has provided the definition for a frequency grid to support DWDM applications. (ITU-T G.694.1) The most commonly used grid is the 100GHz grid, which consist of a spacing of 0.8nm per channel.

Dense Wavelength Division Multiplexing (DWDM)
ITU Grid: C-Band, 100 GHz Spacing
Channel Wavelength Frequency   Channel Wavelength Frequency
number (nm) (GHz)   number (nm) (GHz)
1 1577.03 190100   37 1547.72 193700
2 1576.20 190200   38 1546.92 193800
3 1575.37 190300   39 1546.12 193900
4 1574.54 190400   40 1545.32 194000
5 1573.71 190500   41 1544.53 194100
6 1572.89 190600   42 1543.73 194200
7 1572.06 190700   43 1542.94 194300
8 1571.24 190800   44 1542.14 194400
9 1570.42 190900   45 1541.35 194500
10 1569.59 191000   46 1540.56 194600
11 1568.11 191100   47 1539.77 194700
12 1567.95 191200   48 1538.98 194800
13 1567.13 191300   49 1538.19 194900
14 1566.31 191400   50 1537.40 195000
15 1565.50 191500   51 1536.61 195100
16 1564.68 191600   52 1535.82 195200
17 1563.86 191700   53 1535.04 195300
18 1563.05 191800   54 1534.25 195400
19 1562.23 191900   55 1533.47 195500
20 1561.42 192000   56 1532.68 195600
21 1560.61 192100   57 1531.90 195700
22 1559.79 192200   58 1531.12 195800
23 1558.98 192300   59 1530.33 195900
24 1558.17 192400   60 1529.55 196000
25 1557.36 192500   61 1528.77 196100
26 1556.56 192600   62 1527.99 196200
27 1555.75 192700   63 1527.22 196300
28 1554.94 192800   64 1526.44 196400
29 1554.13 192900   65 1525.66 196500
30 1553.33 193000   66 1524.89 196600
31 1552.52 193100   67 1524.11 196700
32 1551.72 193200   68 1523.34 196800
33 1550.92 193300   69 1522.56 196900
34 1550.12 193400   70 1521.79 197000
35 1549.32 193500   71 1521.02 197100
36 1548.52 193600   72 1520.25 197200



Next to the 100Ghz grid the 50Ghz grid is also used. Solid Optics is able to provide the optics and MUXes for both grids. The 50Ghz grids consists of the 100Ghz grid plus the channels below:

Dense Wavelength Division Multiplexing (DWDM)
ITU Grid: C-Band, 50 Ghz offset
Channel Wavelength Frequency   Channel Wavelength Frequency
number (nm) (GHz)   number (nm) (GHz)
1.5 1576.61 190150   37.5 1547.32 193750
2.5 1575.78 190250   38.5 1546.52 193850
3.5 1574.95 190350   39.5 1545.72 193950
4.5 1574.13 190450   40.5 1544.92 194050
5.5 1573.30 190550   41.5 1544.13 194150
6.5 1572.48 190650   42.5 1543.33 194250
7.5 1571.65 190750   43.5 1542.54 194350
8.5 1570.83 190850   44.5 1541.75 194450
9.5 1570.01 190950   45.5 1540.95 194550
10.5 1569.18 191050   46.5 1540.16 194650
11.5 1568.36 191150   47.5 1539.37 194750
12.5 1567.54 191250   48.5 1538.58 194850
13.5 1566.72 191350   49.5 1537.79 194950
14.5 1565.90 191450   50.5 1537.00 195050
15.5 1565.09 191550   51.5 1536.22 195150
16.5 1564.27 191650   52.5 1535.43 195250
17.5 1563.45 191750   53.5 1534.64 195350
18.5 1562.64 191850   54.5 1533.86 195450
19.5 1561.83 191950   55.5 1533.07 195550
20.5 1561.01 192050   56.5 1532.29 195650
21.5 1560.20 192150   57.5 1531.51 195750
22.5 1559.39 192250   58.5 1530.72 195850
23.5 1558.58 192350   59.5 1529.94 195950
24.5 1557.77 192450   60.5 1529.16 196050
25.5 1556.96 192550   61.5 1528.38 196150
26.5 1556.15 192650   62.5 1527.60 196250
27.5 1555.34 192750   63.5 1526.83 196350
28.5 1554.54 192850   64.5 1526.05 196450
29.5 1553.73 192950   65.5 1525.27 196550
30.5 1552.93 193050   66.5 1524.50 196650
31.5 1552.12 193150   67.5 1523.72 196750
32.5 1551.32 193250   68.5 1522.95 196850
33.5 1550.52 193350   69.5 1522.18 196950
34.5 1549.72 193450   70.5 1521.40 197050
35.5 1548.91 193550   71.5 1520.63 197150
36.5 1548.11 193650   72.5 1519.86 197250



Be aware that Cisco doesn’t follow the the market in terms of channel numbering. You can use the following table to translate between Cisco and regular channels:

 

ITU channel Cisco channel Wavelength (nm)   ITU channel Cisco channel Wavelength (nm)
19.5 1 1561.83   39.5 41 1545.72
20 2 1561.42   40 42 1545.32
20.5 3 1561.01   40.5 43 1544.92
21 4 1560.61   41 44 1544.53
21.5 5 1560.20   41.5 45 1544.13
22 6 1559.79   42 46 1543.73
22.5 7 1559.39   42.5 47 1543.33
23 8 1558.98   43 48 1542.94
23.5 9 1558.58   43.5 49 1542.54
24 10 1558.17   44 50 1542.14
24.5 11 1557.77   44.5 51 1541.75
25 12 1557.36   45 52 1541.35
25.5 13 1556.96   45.5 53 1540.95
26 14 1556.56   46 54 1540.56
26.5 15 1556.15   46.5 55 1540.16
27 16 1555.75   47 56 1539.77
27.5 17 1555.34   47.5 57 1539.37
28 18 1554.94   48 58 1538.98
28.5 19 1554.54   48.5 59 1538.58
29 20 1554.13   49 60 1538.19
29.5 21 1553.73   49.5 61 1537.79
30 22 1553.33   50 62 1537.40
30.5 23 1552.93   50.5 63 1537.00
31 24 1552.52   51 64 1536.61
31.5 25 1552.12   51.5 65 1536.22
32 26 1551.72   52 66 1535.82
32.5 27 1551.32   52.5 67 1535.43
33 28 1550.92   53 68 1535.04
33.5 29 1550.52   53.5 69 1534.64
34 30 1550.12   54 70 1534.25
34.5 31 1549.72   54.5 71 1533.86
35 32 1549.32   55 72 1533.47
35.5 33 1548.91   55.5 73 1533.07
36 34 1548.52   56 74 1532.68
36.5 35 1548.11   56.5 75 1532.29
37 36 1547.72   57 76 1531.90
37.5 37 1547.32   57.5 77 1531.51
38 38 1546.92   58 78 1531.12
38.5 39 1546.52   58.5 79 1530.72
39 40 1546.12   59 80 1530.33