Fibre optic DWDM

Dense Wavelength Division Multiplexing

A newer fiber optic media development for long-range communications is called dense wavelength division multiplexing (DWDM). DWDM multiplies the amount of bandwidth that a single strand of fiber can support.

Specifically, DWDM:

• Enables bidirectional communications over one strand of fiber.
• Can multiplex more than 80 different channels of data (i.e., wavelengths) onto a single fiber.
• Each channel is capable of carrying a 10 Gb/s multiplexed signal.
• Assigns incoming optical signals to specific wavelengths of light (i.e., frequencies).
• Can amplify these wavelengths to boost the signal strength.
• Supports SONET and SDH standards.

Standards:

SONET is an American-based ANSI standard, while SDH is a European-based ETSI and ITU standard. Both are essentially the same and, therefore, often listed as SONET/SDH.

References

• Google DWDM search amazing
• Wavelength-division multiplexing Global Wiki
• ADVA used by BT customer premises equipment