Minimization of Wavelength Conversions

  • Xiaohua Jia
  • Xiao-Dong Hu
  • Ding-Zhu Du
Part of the Network Theory and Applications book series (NETA, volume 9)


In multihop WDM networks where wavelength converters are equipped at some routing nodes, a connection between two communication nodes consists of one or more lightpaths. A wavelength conversion is required at the joint of two lightpaths if they use different wavelengths. Wavelength conversion can be done either electronically or optically. In electronic approach, optic-electronic-optic conversion is required and it causes long delay compared with the transmission of light signals. In all optical approach, the optical signal is allowed in the optical domain throughout the conversion process, however shifting wavelength channels from one to another makes routing/switching complicated. Therefore, in either case, it is desirable to minimize the number of wavelength conversions used to reduce the conversion delay and workload of routing nodes.


Span Tree Maximum Clique Performance Ratio Wavelength Conversion Wavelength Assignment 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer Science+Business Media Dordrecht 2002

Authors and Affiliations

  • Xiaohua Jia
    • 1
  • Xiao-Dong Hu
    • 2
  • Ding-Zhu Du
    • 3
  1. 1.Department of Computer ScienceCity University of Hong KongHong Kong, SAR China
  2. 2.Institute of Applied MathematicsAcademy of Mathematics and System Science, Chinese Academy of SciencesBeijingP.R. China
  3. 3.Department of Computer ScienceUniversity of MinnesotaMinneapolisUSA

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