Software-Defined Networking (SDN) is an innovative approach to network architecture that separates the control plane from the data plane, enabling centralized network management through software applications. Unlike traditional networking, where control functions are embedded in physical devices such as routers and switches, SDN shifts network intelligence to a software-based controller. This centralized controller dynamically manages network traffic, optimizes performance, and enhances security by allowing administrators to configure and automate network behavior using programmable interfaces. By abstracting the underlying hardware, SDN provides greater flexibility, scalability, and adaptability to meet evolving business and technological demands.

The benefits of SDN extend across various industries, particularly in cloud computing, telecommunications, and enterprise networks. It simplifies network provisioning, reduces operational costs, and improves security by enforcing consistent policies across the infrastructure. SDN also facilitates the deployment of advanced networking technologies, such as network function virtualization (NFV), intent-based networking, and zero-trust security frameworks. As organizations increasingly adopt SDN to enhance agility and resilience, it plays a crucial role in supporting modern applications, data centers, and emerging technologies like 5G and the Internet of Things (IoT).

Posts

5GLoR: 5G LAN Orchestration for Enterprise IoT Applications

5G-LAN is an enterprise local area network (LAN) that leverages 5G technology for wireless connectivity instead of WiFi. 5G technology is unique: it uses network slicing to distinguish customers in the same traffic class using new QoS technologies in the RF domain. This unique ability is not supported by most enterprise LANs, which rely primarily on DiffServ-like technologies that distinguish among traffic classes rather than customers. We first show that this mismatch in QoS between the 5G network and the LAN affects the accuracy of insights from the LAN-resident analytics applications. We systematically analyze the root causes of the QoS mismatch and propose a first-of-a-kind 5G-LAN orchestrator (5GLoR). 5GLoR is a middleware that applications can use to preserve the QoS of their 5G data streams through the enterprise LAN. In most cases, the loss of QoS is not due to the oversubscription of LAN switches but primarily due to the inefficient assignment of 5G data to queues at ingress and egress ports. 5GLoR periodically analyzes the status of these queues, provides suitable DSCP identifiers to the application, and installs relevant switch re-write rules (to change DSCP identifiers between switches) to continuously preserve the QoS of the 5G data through the LAN. 5GLoR improves the RTP frame level delay and inter-frame delay by 212% and 122%, respectively, for the WebRTC application. Additionally, with 5GLoR, the accuracy of two example applications (face detection and recognition) improved by 33%, while the latency was reduced by about 25%. Our experiments show that the performance (accuracy and latency) of applications on a 5G-LAN performs well with the proposed 5GLoR compared to the same applications on MEC. This is significant because 5G-LAN offers an order of magnitude more computing, networking, and storage resources to the applications than the resource-constrained MEC, and mature enterprise technologies can be used to deploy, manage, and update IoT applications.

Clairvoyant Networks

We use the term clairvoyant to refer to networks that provide on-demand visibility for any flow at any time. Traditionally, network visibility is achieved by instrumenting and passively monitoring all flows in a network. SDN networks, by design endowed with full visibility, offer another alternative to network-wide flow monitoring. Both approaches incur significant capital and operational costs to make networks clairvoyant. In this paper, we argue that we can make any existing network clairvoyant by installing one or more SDN-enabled switches and a specialized controller to support on-demand visibility. We analyze the benefits and costs of such clairvoyant networks and provide a basic design by integrating two existing mechanisms for updating paths through legacy switches with SDN, telekinesis and magnet MACs. Our evaluation on a lab testbed and through extensive simulations show that, even with a single SDN-enabled switch, operators can make any flow visible for monitoring within milliseconds, albeit at 38% average increase in path length. With as many as 2% strategically chosen legacy switches replaced with SDN switches, clairvoyant networks achieve on-demand flow visibility with negligible overhead.