Software-defined networking control plane for seamless integration of multiple silicon photonic switches in Datacom networks

Abstract

Silicon photonics based switches offer an effective option for the delivery of dynamic bandwidth for future large-scale Datacom systems while maintaining scalable energy efficiency. The integration of a silicon photonics-based optical switching fabric within electronic Datacom architectures requires novel network topologies and arbitration strategies to effectively manage the active elements in the network. We present a scalable software-defined networking control plane to integrate silicon photonic based switches with conventional Ethernet or InfiniBand networks. Our software-defined control plane manages both electronic packet switches and multiple silicon photonic switches for simultaneous packet and circuit switching. We built an experimental Dragonfly network testbed with 16 electronic packet switches and 2 silicon photonic switches to evaluate our control plane. Observed latencies occupied by each step of the switching procedure demonstrate a total of 344 µs control plane latency for data-center and high performance computing platforms.

PINE: Photonic Integrated Networked Energy efficient datacenters (ENLITENED Program) [Invited]

“…The 32-node PINE HPC/datacenter testbed (Fig. 5) includes four 4 × 4 SiP switches and can be configured in both a dragonfly topology [24] and a fat tree topology [25].…”

Photonic switching in high performance datacenters [Invited]

“…This in turn requires a mandatory modification of the routing tables. As shown by Shen et al [84], updating routing tables in OpenFlow type routers takes milliseconds. Even if equipment optimized for fast routing table update is developed, the fact that routing tables must be ideally all updated at the same time across the interconnects further complicates the operation and leads us to posit that topology reconfiguration time at the packet switch level takes several microseconds.…”

Bandwidth steering in HPC using silicon nanophotonics

“…This EPS needs to contain the appropriate flow rule to allow for the incoming signal to be forwarded to the intended destination. The time required for the SDN controller to remove and add a new flow on each EPS is 78 µs per flow [82]. However, the factor that dominates the time in which the link is unusable is the polling time that current commercial EPSs apply to their ports.…”

“…However, the factor that dominates the time in which the link is unusable is the polling time that current commercial EPSs apply to their ports. On our commercial EPSs, the polling time was measured to be 204 ms [82]. Therefore, the overall time that the link cannot be used during network reconfiguration is dominated by the EPS polling time.…”