Network Comparison of C+L-band Transparent versus C-band Translucent Upgrade

We investigate the designs for the capacity upgrade for transparent C-and C+L-band and translucent C-band only; and evaluate them in terms of capacity, energy consumption, cost, and link utilization ratio. Two different transceiver (TRX) implementations, namely Flex and Fix are used in transparent C-and C+L-band and translucent C-band network designs. We investigate networking performance enabled by different upgrade strategies on a reference topology by relying on an accurate optical transport model. We show that lighting the L-band by keeping a transparent approach leads to an increase in network capacity of more than two times. Conversely, applying translucent design to the C-band to improve the spectral efficiency by deploying regenerators results in only modest improvements of capacity. Also, C+L-band transparent design allows to reduce the number of transceivers per bit/sec and to consume almost 4 dB less energy than that required with the C-band translucent design.