A novel forwarding and routing mechanism design in SDN-based NDN architecture

Combining named data networking（NDN） and software-defined networking（SDN） has been considered as an important trend and attracted a lot of attention in recent years. Although much work has been carried out on the integration of NDN and SDN, the forwarding mechanism to solve the inherent problems caused by the flooding scheme and discard of interest packets in traditional NDN is not well considered. To fill this gap, by taking advantage of SDN, we design a novel forwarding mechanism in NDN architecture with distributed controllers, where routing decisions are made globally. Then we show how the forwarding mechanism is operated for interest and data packets. In addition, we propose a novel routing algorithm considering quality of service（QoS） applied in the proposed forwarding mechanism and carried out in controllers. We take both resource consumption and network load balancing into consideration and introduce a genetic algorithm（GA） to solve the QoS constrained routing problem using global network information. Simulation results are presented to demonstrate the performance of the proposed routing scheme.

Optimization Framework for Minimizing Rule Update Latency in SDN Switches

Benefited from the design of separating control plane and data plane,software defined networking(SDN)is widely concerned and applied.Its quick response capability to network events with changes in network policies enables more dynamic management of data center networks.Although the SDN controller architecture is increasingly optimized for swift policy updates,the data plane,especially the prevailing ternary content-addressable memory(TCAM)based flow tables on physical SDN switches,remains unoptimized for fast rule updates,and is gradually becoming the primary bottleneck along the policy update pipeline.In this paper,we present RuleTris,the first SDN update optimization framework that minimizes rule update latency for TCAM-based switches.RuleTris employs the dependency graph(DAG)as the key abstraction to minimize the update latency.RuleTris efficiently obtains the DAGs with novel dependency preserving algorithms that incrementally build rule dependency along with the compilation process.Then,in the guidance of the DAG,RuleTris calculates the TCAM update schedules that minimize TCAM entry moves,which are themain cause of TCAM update inefficiency.In evaluation,RuleTris achieves a median of<12 ms and 90-percentile of<15ms the end-to-end perrule update latency on our hardware prototype,outperforming the state-of-the-art composition compiler CoVisor by～20 times.