Valerija Kamchevska

Reconfigurable SDM switching using novel silicon photonic integrated circuit

Space division multiplexing using multicore fibers is becoming a more and more promising technology. In space-division multiplexing fiber network, the reconfigurable switch is one of the most critical components in network nodes. In this paper we for the first time demonstrate reconfigurable space-division multiplexing switching using silicon photonic integrated circuit, which is fabricated on a novel silicon-on-insulator platform with buried Al mirror. The silicon photonic integrated circuit is composed of a 7 × 7 switch and low loss grating coupler array based multicore fiber couplers. Thanks to the Al mirror, grating couplers with ultra-low coupling loss with optical multicore fibers is achieved. The lowest total insertion loss of the silicon integrated circuit is as low as 4.5 dB, with low crosstalk lower than −30 dB. Excellent performances in terms of low insertion loss and low crosstalk are obtained for the whole C-band. 1 Tb/s/core transmission over a 2-km 7-core fiber and space-division multiplexing switching is demonstrated successfully. Bit error rate performance below 10−9 is obtained for all spatial channels with low power penalty. The proposed design can be easily upgraded to reconfigurable optical add/drop multiplexer capable of switching several multicore fibers.

Experimental Demonstration of Multidimensional Switching Nodes for All-Optical Data Center Networks

This paper reports on a novel ring-based data center architecture composed of multidimensional switching nodes. The nodes are interconnected with multicore fibers and can provide switching in three different physical, hierarchically overlaid dimensions (space, wavelength, and time). The proposed architecture allows for scaling in different dimensions while at the same time providing support for connections with different granularity. The ring topology reduces the number of different physical links required, leading to simplified cabling and easier link management, while optical bypass holds the prospect of low latency and low-power consumption. The performance of the multidimensional switching nodes has been investigated in an experimental demonstration comprising three network nodes connected with multicore fibers. Both high capacity wavelength connections and time-shared subwavelength connections have been established for connecting different nodes by switching indifferent physical dimensions. Error-free performance (BER <; 10-9) has been achieved for all the connections with various granularity in all the investigated switching scenarios. The scalability of the system has been studied by increasing the transmission capacity to 1 Tbit/s/core equivalent to 7 Tbit/s total throughput in a single seven-core multicore fiber. The error-free performance (BER <; 10-9) for all the connections confirms that the proposed architecture can meet the existing

Ring-based all-optical datacenter networks

Ring-based generic network architecture for all-optical datacenters is proposed, offering highly scalable interconnection network with reduced cabling complexity. Simulations show improved performance compared to all-optical fat-tree datacenter architecture with 40%-99% improved connection request blocking and 3%-17% improved resource utilization.

Experimental demonstration of multidimensional switching nodes for all-optical data centre networks

We experimentally demonstrate network nodes that enable SDM/WDM/TDM switching. 1 Tbit/s/core error-free performance is achieved for connections with different granularities being switched between three network nodes interconnected with 7-core multicore fibres.

Synchronization in a Random Length Ring Network for SDN-Controlled Optical TDM Switching

In this paper we focus on optical time division multiplexed (TDM) switching and its main distinguishing characteristics compared with other optical subwavelength switching technologies.We review and discuss in detail the synchronization requirements that allow for proper switching operation. In addition, we propose a novel synchronization algorithm that enables automatic synchronization of software defined networking controlled all-optical TDM switching nodes connected in a ring network. Besides providing synchronization, the algorithmalso can facilitate dynamic slot size change and failure detection. We experimentally validate the algorithm behavior and achieve correct operation for three different ring lengths. Moreover,we experimentally demonstrate data plane connectivity in a ring network composed of three nodes and show successful wavelength division multiplexing space division multiplexing transmission and switching of data bursts when using the proposed algorithm to provide synchronization.

On-Chip SDM Switching for Unicast, Multicast, and Traffic Grooming in Data Center Networks

This letter reports on the use of a novel photonic integrated circuit that facilitates multicast and grooming in an optical data center architecture. The circuit allows for on-chip spatial multiplexing and demultiplexing as well as fiber core switching. Using this device, we experimentally verify that multicast and/or grooming can be successfully performed along the full range of output ports, for different group sizes and different power ratios. Moreover, we experimentally demonstrate SDM transmission and 5 Tb/s switching using the on-chip fiber switch with integrated fan-in/fan-out devices and achieve error-free performance (BER

Silicon photonics for multicore fiber communication

\,\leq \, 10^{\mathrm {\mathbf {-9}}}

The Hi-Ring architecture for datacentre networks

) for a network scenario, including simultaneous unicast/multicast switching and traffic grooming.

COSIGN - developing an optical software controlled data plane for future large-scale datacenter networks

We review our recent work on silicon photonics for multicore fiber communication, including multicore fiber fan-in/fan-out, multicore fiber switches towards reconfigurable optical add/drop multiplexers. We also present multicore fiber based quantum communication using silicon devices.

Experimental demonstration of optical switching of Tbit/s data packets for high capacity short-range networks

This paper summarizes recent work on a hierarchical ring-based network architecture (Hi-Ring) for datacentre and short-range applications. The architecture allows leveraging benefits of optical switching technologies while maintaining a high level of connection granularity. We discuss results of optical switching in the various physical dimensions incorporated in the hierarchical nodes and we discuss recent results on global synchronisation of nodes in a ring topology.