Dynamic wavelength assignment mechanism using decision tree ID3/C4.5 algorithm on WDM ring access networks

Wavelength division multiplexing (WDM) is one of techniques applied in optical network. Making use of this technique can divide spectra into many different channels, and deliver the data with the different transmissions speed and wavelengths. It can increase the bandwidth of the networks, and reduce the wasted bandwidth of networks. Because there are many wavelengths that can be used, the problem of the wavelength assignment is coming soon. To use the wavelength more effectively, a good wavelength assignment algorithm ID3 and C4.0 is proposed to avoid the problem of wavelength conflict, blocking, conversion and tuning latency. In this paper the dynamic wavelength assignment mechanism on WDM ring access network is brought up. On the data transmission and wavelength assignment mechanism, we adopt the packet switch routing mode that is different from the circuit switch mode to establish the light-path. This mechanism does not need to establish the connection of both ends of network node before sending data. Each node (access node) of network in advance set up wavelength assignment rules. When the data passes the OADM (optical add/drop multiplexer) of access node, it dynamically assigns a suitable wavelength to the data depending on the rules. This mechanism resolved the problem of wavelength blocking and channel utilization in circuit switch mode. In this thesis we make use of the decision tree algorithm in the artificial intelligence to produce the wavelength assignment rules. The rule can make a decision reducing the number of optical switching and wavelength conversion, so the transmission delay time can be decreased. The simulation proves that using decision tree algorithm to produce the wavelength assignment rule is able to reduce optical switch switching and wavelength conversion occurrence. Therefore, it minimizes the time of the tuning latency and promotes the transmission performance for the networks.