This paper surveys various ROADM technologies and network architectures and highlights the ECI Telecom approach to implementing a fully flexible DWDM network.

The introduction of ROADM technologies offers service providers greater flexibility by providing any wavelength to any node connectivity without the need to predefine traffic demands. In addition, unlimited changes can be made to already deployed wavelengths. As a result, service providers now benefit from:

• Simplified network design and implementation with lower operating expenses
• Limitless wavelength deployment for faster setup of wavelength services
• Simple reconfiguration of operating wavelengths to meet changes in traffic demands
• Reduced cost of inventory management