Traffic Engineering Requirements Research Articles

Solving Load Balancing Problems in Routing and Limiting Traffic at the Network Edge

This study focuses on creating and investigating models that optimize load balancing in communication networks by managing routing and traffic limitations. The purpose is to use these models to optimize the network’s routing and traffic limitations while ensuring predictable quality of service levels, and adhering to traffic engineering requirements for routing and limiting traffic at the network edge. In order to achieve this aim, a mathematical optimization model was developed based on a chosen optimality criterion. Two modifications of the traffic engineering routing were created, including the linear limitation model (TER-LLM) and traffic engineering limitation (TER-TEL), each considering the main features of packet flow: intensity and priority. The proposed solutions were compared by analyzing various data inputs, including the ratio of flow parameters and the intensity with which packets will be limited at the border router. The study presents recommendations on the optimal use of the proposed solutions based on their respective features and advantages.

A Framework for Classification and Visualization of Elephant Flows in SDN-Based Networks

Long-lived flows termed as elephant flows normally transport large volumes of data in enterprise networks, particularly data center networks. These flows tend to consume a lot of bandwidth and fill up network buffers end-to-end. This causes non-trivial delays for short-lived flows referred to as mice flows which are usually delay-sensitive. Therefore, identifying and handling elephant flows is important for QoS provisioning. In this paper, we present a framework for real-time detection and visualization of elephant flows in SDN-based networks using sFlow. Using our proposed framework, network operators can examine elephant flows through each switch by double-clicking the switch node in the topology visualization UI. Although not in the scope of this paper, but in order to meet traffic engineering requirements, the elephant flows detected and visualized by our proposed framework can be reprioritized, re-scheduled, or routed via dedicated high speed links. We evaluate the proposed framework by using a physical SDN testbed as well as a Mininet-based testbed.

Constrained minimum lightpath affinity routing in multi-layer optical transport networks

In this paper, a new traffic engineering-capable routing and wavelength assignment scheme is proposed to efficiently handle LSP and lightpath setup requests with different QoS requirements on modern multi-layer (fully optical core and time-division multiplexed edge) transport networks. The objectives of the proposed algorithm are to minimize the rejection probability by maximizing the network load balancing and efficiently handling the grooming of several LSPs on the same lightpath while respecting the constraints of the optical node architecture and considering both traffic engineering and QoS requirements. The proposed solution consists of a two-stage RWA algorithm: each time a new request arrives, an on-line dynamic grooming scheme finds a set of feasible lightpaths which fulfill the QoS and traffic engineering requirements; then, the best feasible lightpath is selected, aiming to keep the network unbalancing and blocking probability as low as possible in the medium and long term, according to a novel global path affinity minimization concept. Extensive simulation experiments have been performed in which our on-line dynamic RWA algorithm demonstrated significant performances. Thanks to its optimal network resource usage and to its reasonable computational space and time complexity, the algorithm can be very attractive for the next-generation optical wavelength-switched networks.

The road to carrier-grade Ethernet

Carrier-grade Ethernet is the latest step in the three-decade development of Ethernet. This work describes the evolution of Ethernet technology from LAN toward a carrier-grade operation through an overview of recent enhancements. After reviewing native Ethernet and its transport shortcomings, we introduce the major carrier-grade upgrades. We first discuss the evolution of layer-2 architectures. Then, we detail the service specifications and their QoS and traffic engineering requirements. Finally, we describe the new OAM and resilience mechanisms.