A Survey on OFDM-Based Elastic Core Optical Networking <s> 1) Spectrum-Sliced Elastic Optical Path Network (SLICE) <s> The sustained growth of data traffic volume calls for an introduction of an efficient and scalable transport platform for links of 100 Gb/s and beyond in the future optical network. In this article, after briefly reviewing the existing major technology options, we propose a novel, spectrum- efficient, and scalable optical transport network architecture called SLICE. The SLICE architecture enables sub-wavelength, superwavelength, and multiple-rate data traffic accommodation in a highly spectrum-efficient manner, thereby providing a fractional bandwidth service. Dynamic bandwidth variation of elastic optical paths provides network operators with new business opportunities offering cost-effective and highly available connectivity services through time-dependent bandwidth sharing, energy-efficient network operation, and highly survivable restoration with bandwidth squeezing. We also discuss an optical orthogonal frequency-division multiplexing-based flexible-rate transponder and a bandwidth-variable wavelength cross-connect as the enabling technologies of SLICE concept. Finally, we present the performance evaluation and technical challenges that arise in this new network architecture. <s> BIB001 </s> A Survey on OFDM-Based Elastic Core Optical Networking <s> 1) Spectrum-Sliced Elastic Optical Path Network (SLICE) <s> We investigated the high spectrum efficiency property of the bandwidth-variable optical OFDM (BV-OOFDM) transport networks. In contrast to mixed-line-rate (MLR) networks, BV-OOFDM enables flexible allocation and efficient utilization of the spectral resource. <s> BIB002
An OFDM-based elastic optical network architecture was first proposed in BIB001 [70], referred to as SLICE. Using the sub-carrier multiplexing and flexible spectrum allocation features of O-OFDM technology, a bandwidth-elastic optical path can use just enough spectrum (subcarriers) according to the transmitted data rate. As such, by breaking the fixedgrid wavelength-allocation limitation of WDM, it achieves high spectrum efficiency BIB002 . SLICE supports multiple data rate sub-wavelength or super-wavelength (an optical path that carries traffic at a data rate that is beyond the capacity of a single wavelength/transponder) paths through the introduction of data-rate/bandwidth-variable transponders at the network edge and bandwidth-variable wavelength cross-connects (WXCs) in the network core.