A protection arrangement for an optical switching system includes protection switching for switch planes in the optical core and for ports in the tributary cards. For a multiple layer switch core protection is also provided between layers. A first layer is for switching optical channels. The protection switches used may be 1N, 2N or 3N MEMS optical switches. The 1N MEMS provides for protection switching. The 2N MEMS provides protection switching and testing capability. The 3N MEMS provides for protection switching, testing and backup of the protection switching. Application of these protection switches is shown in lambda plane switch cores, multiple layer switch cores and combined switch cores.