Hybrid SDN Performance: Switching between Centralized and Distributed Modes under Unreliable Control Communication Channels

Software-defined networking generally assumes ideal control channels between controller and network nodes. This may not be the case in challenged environments that are becoming more common due to dense and reduced-coverage 5G deployments and use cases requiring cost-effective wireless transport networks. In this paper, we evaluate the impact on network performance of unreliable controller-to-node communication channels, propose a hybrid SDN (hSDN) solution that switches between centralized and distributed operational modes depending on network conditions, and evaluate this solution under a variety of network scenarios (e.g., link impairments or packet loss ratios) designed to assess its operational limits. The results show that the proposed solution substantially improved the aggregated throughput, particularly when control channel packet loss ratios increased, while only showing a slight increase in average latency (e.g., 28% throughput improvement for 20% control packet losses). This enables network operation in hard conditions under which a canonical centralized SDN control would result in a nonoperational network.

On Telecommunications Thorn Path to the IP World: From Cybersecurity to Artificial Intelligence

The chapter is devoted to the discussion of the telecommunications development strategy. Communication specialists all around the world are facing the problem: how to shift from circuit switching to packet switching. The same problem is the main challenge for the US Department of Defense. We discuss the Defense Information System Network move from circuits to packets, namely, “Joint Vision 2010” doctrine - the implementation of signaling protocol #7 and Advanced Intelligent Network, and “Joint Vision 2020” - the network transformation by the transition to Assured Services Session Initiation Protocol and Multifunctional SoftSwiches. We describe some packet switching shortcomings during the implementation of Joint Vision 2020, namely, the failed GSM-O contract and Joint regional security stacks failures. The Defense Department’s newly released cloud strategy positions the general-purpose Joint Enterprise Defense Infrastructure (JEDI) cloud initiative as the foundation. The strategy emphasizes a cloud hierarchy at DoD, but JEDI cloud strategy leaves a series of unanswered questions relating to the interoperability of clouds. The JEDI cloud strategy has based on Artificial Intelligence Initiative. We conclude that the long-term channel - packet coexistence seems inevitable, especially in the face of growing cyber threats.

A Beacon-less Multi-channel Packet Forwarding Scheme in Vehicular Networks

The ad-hoc vehicular network is a sub stream of an ad-hoc mobile network where the nodes can converse and know each other by their periodic control packet dissemination. In vehicular network communication, the available bandwidth is limited. The parallel and multi-vehicle channel access will create an unwanted delay during the packet dissemination. The node may compete with each other to access the channel during parallel communication. The simultaneous channel access will increase network overload. The proposed approach will minimize the channel access collision through the variable time slots. Before any data dissemination, the node will send a Channel Booking Request (CBR) message to a correspondent node. The spectrum allocation is based on the type of vehicle and message_code. The concept has experimented with traditional routing protocols for overtaking assistance. The proposed approach is compared with the packet delivery rate, jitter, and packet loss rate.