Cwdm vs Dwdm
To best describe DWDM (coarse wavelength division multiplexing) and DWDM (dense wavelength division multiplexing), you must first understand how WDM (wavelength division multiplexing) operates. WDM is multiplexing several optical signals on a single fibre by using wavelengths which are essentially colours of the laser light; to transmit different signals ranging from 2.5Gbps to 40Gbps. The device that connects the signals together is a multiplexor, and the one that splits them apart on the other end is called a demultiplexer. The theory behind WDM is that it allows you to transmit and receive information through different optical channels which is called WDM. This includes wavelength division multiplexing and frequency division multiplexing.
Wavelength is essentially the colour of the laser being transmitted; an easy interpretation of this is in the form of a beautiful rainbow (with gold and cotton candy at each end). Each channel is represented as a coloured laser that transmits data across the network. So in theory, each colour of the rainbow (data) is transmitted through the mux (multiplexer) to form one data entity, which in turn comes out of the demux (demultiplexer) and spreads the rainbow out to the receiving side of the network and vice versa or even bidirectional.
Now, there are a number of differences between CWDM and DWDM technologies. Firstly, DWDM is the first choice in regards to fibre applications, but in saying that, the cost of the technology is very steep, and this is when CWDM was brought in through high demand. Also, the channel spacing through CWDM is wider, therefore leaving room for more light in a single fibre, which in turn leads to about 5 or 6 wavelengths. CWDM uses a modulation laser which is an uncooled laser, DWDM uses a cooling laser. A cooling laser tunes by temperature, whilst the uncooled laser adopts electronic tuning. Temperature tuning is difficult to get accurate results because the temperature is in very wide sections
Wavelength is essentially the colour of the laser being transmitted; an easy interpretation of this is in the form of a beautiful rainbow (with gold and cotton candy at each end). Each channel is represented as a coloured laser that transmits data across the network. So in theory, each colour of the rainbow (data) is transmitted through the mux (multiplexer) to form one data entity, which in turn comes out of the demux (demultiplexer) and spreads the rainbow out to the receiving side of the network and vice versa or even bidirectional.
Now, there are a number of differences between CWDM and DWDM technologies. Firstly, DWDM is the first choice in regards to fibre applications, but in saying that, the cost of the technology is very steep, and this is when CWDM was brought in through high demand. Also, the channel spacing through CWDM is wider, therefore leaving room for more light in a single fibre, which in turn leads to about 5 or 6 wavelengths. CWDM uses a modulation laser which is an uncooled laser, DWDM uses a cooling laser. A cooling laser tunes by temperature, whilst the uncooled laser adopts electronic tuning. Temperature tuning is difficult to get accurate results because the temperature is in very wide sections