Methods and apparatus for a reconfigurable optical add-drop multiplexer (ROADM) cluster node are provided. In some embodiments, the ROADM cluster node includes a set of g line chassis for performing line functionality. In some embodiments, the ROADM cluster node further includes a set of h add-drop chassis for performing add-drop functionality. In some embodiments, each of the g line chassis includes a set of N line cards and a set of M interconnect cards. In some embodiments, the ROADM cluster node further includes a set of M interconnect chassis configured for interconnecting each line chassis to each other line chassis. In some embodiments, the set of M interconnect chassis is further configured for interconnecting each line chassis to each of the h add-drop chassis. In some embodiments, the ROADM cluster node separates the line functionality and add-drop functionality. In some embodiments, 1.15N≤M≤1.5N.