Peter Bull

Flow Based Security for IoT Devices Using an SDN Gateway

With near exponential growth predicted in the number of Internet of Things (IoT) based devices within networked systems there is need of a means of providing their flexible and secure integration. Software Defined Networking (SDN) is a concept that allows for the centralised control and configuration of network devices, and also provides opportunities for the dynamic control of network traffic. This paper proposes the use of an SDN gateway as a distributed means of monitoring the traffic originating from and directed to IoT based devices. This gateway can then both detect anomalous behaviour and perform an appropriate response (blocking, forwarding, or applying Quality of Service). Initial results demonstrate that, while the addition of the attack detection functionality has an impact on the number of flow installations possible per second, it can successfully detect and block TCP and ICMP flood based attacks.

Pre-emptive Flow Installation for Internet of Things Devices within Software Defined Networks

The predicted prevalence of both Internet of Things (IoT) based devices and the concept of Software Defined Networking (SDN) as a new paradigm in networking, means that consideration is required for how they will interact. Current SDN implementations operate on the principle that on receiving an unrecognised packet, a switch will query a centralised controller for a corresponding rule. Memory limitations within current switch devices dictate that this rule can only be stored for a short period of time before being removed, thus making it likely that the relatively infrequent data samples sent from IoT devices will have a transmission interval longer than this timeout. This paper proposes a Pre-emptive Flow Installation Mechanism (PFIM) that dynamically learns the transmission intervals of periodic network flows and installs the corresponding rules within a switch, prior to the arrival of a packet. A proof-of-concept implementation shows this to have a significant effect on reducing the delay experienced by these flows.

A quality of service framework for dependability in large-scale distributed systems

As recognition grows within industry for the advantages that can be gained through the exploitation of large-scale dynamic systems, a need emerges for dependable performance. Future systems are being developed with a requirement to support mission critical and safety critical applications. These levels of criticality require predictable performance and as such have traditionally not been associated with adaptive systems. The software architecture proposed for such systems takes its properties from the service-oriented computing paradigm and the communication model follows a publish/subscribe approach. While adaptive, such architectures do not, however, typically support real-time levels of performance. There is scope, however, for dependability within such architectures through the use of Quality of Service (QoS) methods. QoS is used in systems where the distribution of resources cannot be decided at design time. In this paper a QoS based framework is proposed for providing adaptive and dependable behaviour for future large-scale dynamic systems through the flexible allocation of resources. Simulation results are presented to demonstrate the benefits of the QoS framework and the tradeoffs that occur between negotiation algorithms of varying complexities.

A Multi-Class Mobility Model for Dynamic and Dependable Systems

The complex interactions inherent in mobile, dynamic systems require a representative model of node movement properties. Dynamic systems proposed within industry, particularly in the military domain, have a requirement for dependable communication and include heterogeneous nodes (varying from personal devices, to aircraft with complex sensors). Existing node mobility models have been found to not be adequate for capturing the properties of these systems due to their tendency to focus on systems with nodes of a single type, or characteristic. In this paper, a Multi-Class Mobility Model (MCMM) is proposed. This is a hybrid, class-based model operating with both single entity and group mobility patterns. Within this model nodes can be specified in a range of classes, based on their movement properties (including acceleration/deceleration factors and maximum speed). Simulation based experimentation implements MCMM, in conjunction with a previously proposed Quality of Service framework. This provides an opportunity to evaluate the mobility model in terms of its affect on system utilisation and stability. Through simulation, MCMM is compared with existing Random Walk/Random Waypoint and Reference Point Group Models. MCMM is shown to offer a more representative node movement, resulting in a comparable and representative system utilisation. This is achieved while offering a more stable system model with less communication disruption due to lost network connections.

A quality of service framework for adaptive and dependable large scale system-of-systems

There is growing recognition within industry that for system growth to be sustainable, the way in which existing assets are used must be improved. Future systems are being developed with a desire for dynamic behaviour and a requirement for dependability at mission critical and safety critical levels. These levels of criticality require predictable performance and as such have traditionally not been associated with adaptive systems. The software architecture proposed for such systems is based around a publish/subscribe model, an approach that, while adaptive, does not typically support critical levels of performance. There is, however, the scope for dependability within such architectures through the use of Quality of Service (QoS) methods. QoS is used in systems where the distribution of resources cannot be decided at design time. A QoS based framework is proposed for providing adaptive and dependable behaviour for future large-scale system-of-systems. Initial simulation results are presented to demonstrate the benefits of QoS.

Constraint-aware software-defined network for routing real-time multimedia

Traditional Ethernet-based IP networks do not have the capability to provide the Quality of Service (QoS) required for professional real-time multimedia applications. This is because they operate on a best-effort network service model that does not provide service guarantee. Network operators and service providers require a novel network architecture to efficiently handle the increasing demands of this changing network domain. Software-Defined Networking has emerged as an effective network architecture that decouples the control plane and data plane, which makes it capable of handling the dynamic nature of future network functions and intelligent applications while reducing cost through simplified hardware, software, and management. This paper presents an SDN architecture for real-time low latency applications that offer adaptive path provisioning based on the calculated end-to-end delay, available bandwidth, and traditional shortest path first algorithm. The SDN architecture utilises the Ryu OpenFlow application programming interface (API) to perform real-time monitoring to collect network statistics and computes the appropriate paths by using this information. The experiment to ascertain the feasibility and evaluate the effectiveness of this approach is carried out in an emulated network environment using Mininet.

A Raspberry Pi Based Scalable Software Defined Network Infrastructure for Disaster Relief Communication

Disasters, both natural and man-made, can occur at any time or place in the world; aid is then required to support the victims of the disaster and to provide humanitarian support within the disaster zone. The first 24-48 hours after a disaster are a critical time for first responders in administering aid to the victims. This is known as the golden 24 hours [1] where 85% to 95% of live rescues are made. To support this effort, a rapidly deployable, scalable, and low cost communication infrastructure is required. This paper proposes the use of low-cost Single Board Computers, in combination with scalable containerised network services (e.g. VOIP, Web Services, etc.), utilising Software Defined Network based control to allow the centralised management of devices. A Raspberry Pi based prototype setup is detailed, and initial performance tests are presented as a means of confirming the technological viability of the concept under a number of different topology configurations.

Performance Evaluation of a New Flexible Time Division Multiplexing Protocol on Mixed Traffic Types

The broadcasting industry has recently begun to adopt statistical multiplexing based network platform in their workflow to support professional live audio/video (AV) transmission instead of the Time Division Multiplexing (TDM) based system. These audio-over-packet switched systems require a carefully designed and managed network to ensure key quality measures of the real-time (RT) media, such as low jitter and low latency. Often the best effort traffic or different types of media are still physically or logically segregated from these dedicated systems, or require large redundant links. The proposed Flexilink architecture is an alternative that combines both circuit switched and best effort features. However, there is no research evaluation that shows the actual performance of this proposed architecture. In this paper, we give a simulation based study and critical evaluation of the performance of the Flexilink network. The simulation results show that Flexilink has a better and more stable RT performance when compared with both Ethernet and priority queueing networks, especially when given a burst of traffic and/or multiple RT traffic sources. In addition, Unlike other networking protocols, jitter in Flexilink is below the audible threshold.

Performance Implication and Analysis of the OpenFlow SDN Protocol

Software Defined Networks provide the ability to manage networks from a centralised point through separating control plane from the data plane. This brings opportunities in terms of manageability, flexibility and cost savings in network operations. This centralisation, however, also brings about a potentially serious performance bottleneck and poses a scalability issue in high performance networks. This paper investigates performance of Software Defined Networks in general, and the OpenFlow protocol, to provide insight into the components of control path delay incurred by packets and ways to optimise flow forwarding. Two Openflow controllers (Floodlight and Pox) were used to validate performance measurements in relation to their theoretical composition. Secondly, the packet processing dynamics of switches, in particular OpenVSwitch are examined, looking at the control packet forwarding behaviour in the kernel module to meet high performance network and traffic engineering demand.

A Trust Management Framework for Network Applications within an SDN Environment

Software Defined Networking (SDN) is an emerging paradigm that changes the way networks are managed by separating the control plane from data plane and making networks programmable. The separation brings about flexibility, automation, orchestration and offers savings in both capital and operational expenditure. Despite all the advantages offered by SDN it introduces new threats that did not exist before or were harder to exploit in traditional networks, making network penetration potentially easier. One of the key threat to SDN is the authentication and authorisation of network applications that control network behaviour (unlike the traditional network where network devices like routers and switches are autonomous and run proprietary software and protocols to control the network). This paper proposes a mechanism that helps the control layer authenticate network applications and set authorisation permissions that constrict manipulation of network resources.