Forwarding Element Research Articles

A Machine Learning-Based Anomaly Prediction Service for Software-Defined Networks

Software-defined networking (SDN) has gained tremendous growth and can be exploited in different network scenarios, from data centers to wide-area 5G networks. It shifts control logic from the devices to a centralized entity (programmable controller) for efficient traffic monitoring and flow management. A software-based controller enforces rules and policies on the requests sent by forwarding elements; however, it cannot detect anomalous patterns in the network traffic. Due to this, the controller may install the flow rules against the anomalies, reducing the overall network performance. These anomalies may indicate threats to the network and decrease its performance and security. Machine learning (ML) approaches can identify such traffic flow patterns and predict the systems' impending threats. We propose an ML-based service to predict traffic anomalies for software-defined networks in this work. We first create a large dataset for network traffic by modeling a programmable data center with a signature-based intrusion-detection system. The feature vectors are pre-processed and are constructed against each flow request by the forwarding element. Then, we input the feature vector of each request to a machine learning classifier for training to predict anomalies. Finally, we use the holdout cross-validation technique to evaluate the proposed approach. The evaluation results specify that the proposed approach is highly accurate. In contrast to baseline approaches (random prediction and zero rule), the performance improvement of the proposed approach in average accuracy, precision, recall, and f-measure is (54.14%, 65.30%, 81.63%, and 73.70%) and (4.61%, 11.13%, 9.45%, and 10.29%), respectively.

An efficient flow-based multi-level hybrid intrusion detection system for software-defined networks

Software-defined networking (SDN) is a novel networking paradigm that provides enhanced programming abilities, which can be used to solve traditional security challenges on the basis of more efficient approaches. The most important element in the SDN paradigm is the controller, which manages the flows of each correspondence forwarding element (switch or router). Flow statistics provided by the controller are considered to be useful information that can be used to develop a network-based intrusion detection system. Therefore, in this paper, we propose a 5-level hybrid classification system based on flow statistics in order to attain an improvement in the overall accuracy of the system. For the first level, we employ the k-nearest neighbor approach (kNN); for the second level, we use the extreme learning machine (ELM); and for the remaining levels, we utilize the hierarchical extreme learning machine (HELM) approach. In comparison with conventional supervised machine learning algorithms and other state-of-the-art methodologies based on the NSL-KDD benchmark dataset, the experimental study showed that our system achieves a good accuracy (84.29%), with an ability to detect new attacks that reaches 77.18%. Therefore, our approach presents an efficient approach for intrusion detection in SDNs.

Efficient SVC Multicast Streaming for Video Conferencing With SDN Control

Video conferencing consumes a substantial portion of network bandwidth and have strong latency requirements. In traffic engineering, software-defined networking (SDN) optimizes video conferencing performance through flexible controls. SDN switches process packets by leveraging ternary content-addressable memory (TCAM), which is a high-speed hardware-based packet forwarding element. However, TCAM is not cost-effective and limited in space, especially in SDN, as it requires more TCAM space to match more packet fields. Previous studies rely on SDN to handle SVC video streaming; however, none considers TCAM space in SDN switches. In this paper, we propose a novel SVC multicast streaming scheme named adaptive SDN-based SVC multicast (ASCast). Each video layer forms a multicast tree, and we formulate a linear programming problem for the tree construction. To address the problem, we design static and dynamic heuristic algorithms to build multicast trees and maximize overall video quality with limited TCAM space. Moreover, to reduce TCAM space consumption, we carefully consider multicast integer programming address assignment for video layers and forwarding rule installation. Based on our evaluation, ASCast provides a 35% higher video data rate and installs 66% fewer forwarding rules into switches than other SVC video multicast schemes.

Design and Implementation of ForCES Protocol

This paper proposes the design and implementation of the ForCES protocol, specifically FP logical point of the ForCES architecture, which is strictly the communication between the CE (Control Element) and the FE (Forwarding Element). It is a flexible and reprogrammable architecture that is established within the specifications issued and defined by the ForCES working group, and consists of elaboration of a protocol that carries information between both elements. In order to comprobate the correct functioning of the implemented the ForCES protocol, is we provide a network testbed scenario, which consist an application client-server. Each device has equipped with the application which based on Java language, that allows the researcher to be able to compare the typical functionality of a conventional router with a router based in architecture ForCES. It allows taking advantage of the benefits of this architecture to reprogram different and new functionalities.

Performance optimisation of control channel in ForCES‐based software defined network

The traditional network architecture cannot meet the growing needs of increasingly diverse network applications. The new generation network architectures, software defined network (SDN) which have features of high openness, flexibility, scalability and high controllability have widely been studied. However, a series of new problems are also produced in this new architecture, such as security problem resulted from the high openness, and performance problem resulted from the high flexibility. Currently, the researchers are mainly concentrated in the implementation and standardisation of SDN. There is no good approach to evaluate and optimise the system performance. This studies the performance problems unresolved in SDN research area, and proposed an idea and method to analyse the control channel of ForCES (Forwarding and Control Element Separation)-based SDN by using the stochastic network calculus theory. First, the architecture of ForCES-based SDN is introduced. Then, the performance model of the channel is given. Based on the model, an optimisation method to performance is detailed. This study also gives a simulation by using NS-2 (Network Simulator, Version 2) to verify the correctness and reliability of the performance model.

5G‐Crosshaul: An SDN/NFV control and data plane architecture for the 5G integrated Fronthaul/Backhaul

AbstractThis paper presents the control and data plane architecture design for a 5G transport solution (5G‐Crosshaul) with the aim of integrating the fronthaul and backhaul network segments in a common transport stratum. The control plane relies on the Software‐defined networking/Network Functions Virtualization concept to control and orchestrate the different elements of the network (the 5G‐Crosshaul control infrastructure). The data plane is based on an mixed optical/packet‐based forwarding entity (the 5G‐Crosshaul forwarding element) that leverages the benefits of optical passthrough with the statistical multiplexing of packet‐based transmission, working on top of a common frame format for both, fronthaul, and backhaul traffic (the 5G‐Crosshaul common frame). In addition to the main architecture design, this work includes the impact of providing multi‐tenancy support into the architecture of the overall system, in order to share the costs of building and operating the infrastructure among different operators.This architecture opens the 5G transport network as a service for innovative network applications on top (such as multi‐tenancy, and resource management), provisioning the required network and IT resources in a flexible, cost‐effective, and abstract manner. The proposed design supports the concept of network slicing pushed by the industry for realizing a truly flexible, sharable, and cost‐effective future 5G system. Copyright © 2016 John Wiley & Sons, Ltd.

A Method of ForCES Virtualization

Programmability and virtualization have both become the trends of next generation networks. ForCES (Forwarding and Control Element Seperation) is a new programmable framework for network element. We introduce virtualization into ForCES, propose a method of ForCES virtualization, design its framework, implement a prototype system named vForTER, and test its performance in different scenarios. Test results show that we can flexibly build isolated virtual routers in one physical ForCES network element. And the influences to UDP forwarding rate, TCP out of order packets rate, and RTT are very limited. ForCES network elements supporting with both programmability and virtualization can be used as core infrastructure in future networks.

ForSA - A new software defined network architecture based on forCES

In recent years, SDN (Software Defined Network) as a new network architecture has become the hot research point. Meanwhile, the well-known OpenFlow-based SDN got a lot of attention. But it can't provide a flexible and effective network resource description method. As an open programmable technology, ForCES (Forwarding and Control Element Separation) has also been concerned. However, ForCES is confined within a single network node and cannot be applied to the entire network. This paper proposes a new architecture - ForSA (ForCESbased SDN architecture). The architecture is added a configuration layer based on the traditional SDN architecture, which solves the problem that the northbound interface is not clear between the application layer and the control layer in the SDN architecture. ForSA also implements the compatibility within various forwarding devices in the forwarding layer.

FE-brick: Re-definition and Re-design of FE Model in Next-Generation Router Architecture

In traditional router, it usually consists of forwarding element (FE) and control element (CE). However, there is a tight coupling between FE model and logical functions, thus restricting service innovation and user customized ability. In this context, we explore the insightful prospect of functional integration between logical function-based FE model and strategy-driven FE model to propose a new FE model. In this paper, we firstly propose an idea of FE-Brick model for next-generation router architecture, which includes two types of elements: logical function-based FE (LFFE) and strategy-driven FE (SFE). LFFE is a collection of logical functions, which is the same as FE model in traditional routers; and SFE uses flow-strategy to determine forwarding behavior of each packet. FE model can be regarded as a cluster of SFEs and LFFEs, where these elements are optionally interconnected in the similar way as the “building block” game. At last, we establish two demos on FE-Brick model and further evaluate their performance.

An Analysis and Design of the Redirection Schema in ForCES

The idea of Forwarding and Control Element Separation has widely accepted by next generation network researchers, the regain attention of IETF (The Internet Engineering Task Force) ForCES (Forwarding and Control Element Separation) is the best proof. An IP tunnel-based redirection schema was proposed to solve the problem of routing protocol messages interaction between ForCES router and the external merchant routers. The technology of network virtualization is introduced to map network interface from ForCES FE (Forwarding Element) to CE (Control Element) which collaborating with the redirect schema.

The Design and Research of Cluster Router Based on ForCES Protocol

Cluster router is the trend of router development in the future, it enables every router in cluster to cooperate with each other very well. Besides, it greatly expands the capacity of router, and makes the network topology and routing strategies become simple and clear. This paper proposed a architecture based on Forwarding and Control Element Separation (ForCES) cluster, including control module and forwarding module, they are composed of a large number of PCs. The architecture solved the problem of the dynamic service deployment of Logical Function Block (LFB) model and so on, which is an evidence of improving the performance of the existing router by achieving the forwarding model.

ForCES Architecture Router Models in OPNET

Open reconfigurable router (ForCES) is based on the separation of control parts and forwarding parts that can satisfy the open programmable request of the next generation router, and is the next generation router's development direction. At present, the research on ForCES architeture router has completed the system structure and interface standard protocol design, and realized the basic logic function blocks (LFBs) of the control element (CE) and forwarding element (FE), ForCES prototypemachine has also succeeded in operation. However, the performance of any software and protocol must be inspected. Performance evaluation can adopt queuing theory、random Petri nets、 stochastic process algebra and OPNET software, etc. OPNET with user-friendly interface and stratified modeling thought can simplify the process of modeling, clear modeling methodology. The paper adopts OPNET Modeler simulation software to study on ForCES architecture router performance.

Analysis and Implementation of an Open Programmable Router Based on Forwarding and Control Element Separation

A router architecture based upon ForCES (Forwarding and Control Element Separation), which is being standardized by IETF ForCES working group, gains its competitive advantage over traditional router architectures in flexibility, programmability, and cost-effectiveness. In this paper, design and implementation of a ForCES-based router (ForTER) is illustrated. Firstly, the implementation architecture of ForTER is discussed. Then, a layered software model, which well illustrates ForCES features, is proposed. Based on the model, design and implementation of Control Element (CE) and Forwarding Element (FE) in ForTER are introduced in detail. Moreover, security for ForTER is considered and an algorithm to prevent DoS attacks is presented. Lastly, experiments of ForTER are illustrated for routing and running routing protocols, network management, DoS attack prevention, etc. The experimental results show the feasibility of the ForTER design. Consequently, the ForTER implementation basically testifies the feasibility of ForCES architecture and some IETF ForCES specifications.

Dynamic service deployment in a distributed heterogeneous cluster based router (DHCR)

This paper presents the design, implementation and evaluation of an extensible, scalable and distributed heterogeneous cluster based programmable router, called DHCR (Distributed Heterogeneous Cluster based Router), capable of supporting and deploying network services at run time. DHCR is a software IP router relying on heterogeneous cluster composed of separated computers with different hardware and software architecture capabilities, running different operating systems and interconnected through a high speed network connection. The DHCR ensures dynamic deployment of services and distributed control of router components (forwarding and routing elements) over heterogeneous system environments. The DHCR combines the IETF ForCES (Forwarding and Control Element Separation) architecture with software component technologies to meet the requirements of the next generation software routers. To ensure reliable and transparent communication between separated, decentralized and heterogeneous router components, the CORBA based middleware technology is used to support the DHCR internal communication. The paper also explores the use of the CORBA Component Model (CCM) to design and implement a modular, distributed and heterogeneous forwarding path for the DHCR router architecture. The CCM based forwarding plane ensures dynamic reconfiguration of the data path topology needed for low-level service deployment. Results on achievable performance using the proposed DHCR router are reported.

Formalization and Analysis of Routing Loops by Inconsistencies in IP Forwarding Tables

The effect of inconsistencies in forwarding tables on the reachability of IP packets is evaluated. To improve a router's availability, in the architecture of current routers, the control element is separated from the forwarding element. However, a router with the current architecture cannot handle a notification for which the topology of the network system changes when its control element has stopped. In such a case, the router cannot update its own forwarding table, and an inconsistency between the forwarding tables of the router and those of the other routers will occur. To investigate the influence of this inconsistency, we formalize the network system, and derive the conditions under which such an inconsistency leads to unreachable routes. After that, the number of routes that are unreachable is evaluated by simulations. These simulations show that routing loops occur more frequently under the condition that a failed node is close to the restarting node or fewer links exist in the network system.

Functions and operations of CEBus routers

A router is the device in the CEBus network which connects different media. A router intelligently forwards packets onto adjacent media and maintains the tree-structure topology. These functions are provided though the interaction of four elements the communications element, the forwarding element, the directory routing table element, and the network topology protocol element. These elements, combined with the services of the other layers of the router, relieve the nodes of the costly task of network maintenance.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>