Cost-effective data plane solutions based on OFDM technology for flexi-grid metro networks using sliceable bandwidth variable transponders

In an evolutionary metro network scenario, it is proposed to adopt flexi-grid technologies and centralize the IP functionality, locating the Broadband Remote Access Servers (BRASes) in fewer sites of a regional photonic mesh network, in order to reduce CapEx. Therefore, cost-effective data plane solutions, able to support multiple low bit rate connections, using 12.5 GHz channels, are required for this network segment. In this paper, we present a cost-effective bandwidth variable transponder (BVT) based on OFDM technology suitable for flexi-grid metropolitan area network (MAN), using low-complexity digital signal processing (DSP) and direct detection (DD). The design guidelines are provided for this data plane solution, which has been numerically analyzed and experimentally validated in a photonic mesh network. Furthermore, a sliceable BVT architecture is proposed for enhancing the capacity of the BRAS node in order to serve several Multi-Tenant Units (MTUs).