Difference between WDM and DWDM

The main comparison between WDM and DWDM is one of degree only. DWDM has a greater overall capacity so DWDM spaces the wavelength more closely than WDM. Here this post gives the information about WDM vs DWDM to better understand this topic.

Difference between WDM and DWDM:
  • WDM stands for wavelength division multiplexing while DWDM stands for dense wavelength division multiplexing.
  • In WDM the number of the light source are used each emits the light of different wavelength but in DWDM utilized closely spaces channels.
  • In WDM channel spacing reduces to 1.6 nm or less while in DWDM channel spacing is small 200 GHz and small.
  • In WDM optical multiplexer is used as the input side to multiplex these signal while in DWDM assign the incoming optical signal to specific frequency multiplex them for transport over a single fiber.
  • In the WDM method, all signal arrives at the same time instead of being distributed across time slots while in DWDM multiple channels of information carried over the same fiber each using individual wavelength.
  • In DWDM cost per channel is high compared to WDM.
  • In WDM number of channel delivered only two while in DWDM number of channel delivered around a hundred.
  • 1310 nm laser used in conjunction with 1550 nm lasers while in DWDM is qualified only for system Z only.