This paper investigated the influence of the waveband parameters on the number of ports of optical cross-connect (OXC) in waveband switching networks. The concept of waveband switching has been studied to decrease size of OXC when the number of wavelength increases, and the waveband parameters influence the size of OXC. We defined two waveband parameters; One is the number of path in a waveband and another is minimum number of the paths to group. The later waveband parameter means to allow several unused wavelength in a waveband. We evaluated the number input ports of OXC and the number of required wavelength with changing the parameters. The routing algorithm takes account of the delay of routes and of equalization of the number of wavelength in a link. Waveband path groups several wavelength paths with the same part of route in this simulation. Numerical experiments show that the wide bandwidth of a waveband saves the number of ports of OXC when the network has large traffic volume. On the other hand, if unused wavelength is allowed in a waveband, the number of port of OXC can be decreased, but the maximum number of wavelength in network is much required.© (2010) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.