Is the set of technique that allow the
simultaneous transmission of multiple
       signals across a single data link.
Multiplexing




      Analog                        Digital


                                     TDM
FDM            WDM

                                              diagram
   a multiplexing technique working in the
    wavelength domain
   An analog multiplexing technique to
    combine optical signal.
   The concept was first published in
    1970, and by 1978 WDM systems were
    being realized in the laboratory. The first
    WDM systems only combined two signals.
    Modern systems can handle up to 160
    signals and can thus expand a basic 10
    Gbit/s fiber system to a theoretical total
    capacity of over 1.6 Tbit/s over a single
    fiber pair.
   In fiber-optic
    communications
    Wavelength –division
    multiplexing (WDM)
    is a technology which
    multiplexes multiple
    optical carrier signals
    on a single optical
    fiber by using
    different (colours) of
    laser light to carry
    different signals.
With the exponential growth in communications,
     caused mainly by the wide acceptance of the
     Internet, many carriers are finding that their
        estimates of fiber needs have been highly
 underestimated. Although most cables included
many spare fibers when installed, this growth has
 used many of them and new capacity is needed.
1)installing more cables,

2) increasing system bit rate to multiplex
   more signals

3) wavelength division multiplexing.
1)CWDM
2)DWDM
   DWDM
   No official or standard definition
   Implies more channels more closely spaced
    that WDM
    DWDM-based networks create a lower cost
    way to quickly respond to customers'
    bandwidth demands and protocol changes.
   A key advantage to DWDM is that it's
    protocol- and bit-rate independent.
   CWDM
   No official or standard definition
   number of channals is fewer than in dense
    wavelength division multiplexing (DWDM) but
    more than in standard wavelength division
    multiplexing (WDM).
   Laser emmission
   CWDM system have channel at wavelengths
    spaced 20 nanometers (nm).
   DWDM 0.4 nm spacing
   Energy
   tolerance
•   WDM technology allows multiple
    connections over one fiber thus reducing
    fiber plant requirement.
    – This is mainly beneficial for long-haul
      applications.
    – Campus applications require a cost benefit
      analysis.
•   WDM technology can also provide fiber
    redundancy.
•   WDM provides a managed fiber service.
Wavelength division multiplexing

Wavelength division multiplexing

  • 4.
    Is the setof technique that allow the simultaneous transmission of multiple signals across a single data link.
  • 5.
    Multiplexing Analog Digital TDM FDM WDM diagram
  • 6.
    a multiplexing technique working in the wavelength domain  An analog multiplexing technique to combine optical signal.
  • 7.
    The concept was first published in 1970, and by 1978 WDM systems were being realized in the laboratory. The first WDM systems only combined two signals. Modern systems can handle up to 160 signals and can thus expand a basic 10 Gbit/s fiber system to a theoretical total capacity of over 1.6 Tbit/s over a single fiber pair.
  • 8.
    In fiber-optic communications Wavelength –division multiplexing (WDM) is a technology which multiplexes multiple optical carrier signals on a single optical fiber by using different (colours) of laser light to carry different signals.
  • 10.
    With the exponentialgrowth in communications, caused mainly by the wide acceptance of the Internet, many carriers are finding that their estimates of fiber needs have been highly underestimated. Although most cables included many spare fibers when installed, this growth has used many of them and new capacity is needed.
  • 11.
    1)installing more cables, 2)increasing system bit rate to multiplex more signals 3) wavelength division multiplexing.
  • 12.
  • 13.
    DWDM  No official or standard definition  Implies more channels more closely spaced that WDM  DWDM-based networks create a lower cost way to quickly respond to customers' bandwidth demands and protocol changes.  A key advantage to DWDM is that it's protocol- and bit-rate independent.
  • 14.
    CWDM  No official or standard definition  number of channals is fewer than in dense wavelength division multiplexing (DWDM) but more than in standard wavelength division multiplexing (WDM).  Laser emmission
  • 15.
    CWDM system have channel at wavelengths spaced 20 nanometers (nm).  DWDM 0.4 nm spacing  Energy  tolerance
  • 16.
    WDM technology allows multiple connections over one fiber thus reducing fiber plant requirement. – This is mainly beneficial for long-haul applications. – Campus applications require a cost benefit analysis. • WDM technology can also provide fiber redundancy. • WDM provides a managed fiber service.