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In the recent years, HTTP Adaptive Bit Rate (ABR) streaming including Dynamic Adaptive Streaming over HTTP (DASH) has become the most popular technology for video streaming over the Internet. The client device requests segments of content using HTTP, with an ABR algorithm selecting the quality at which to request each segment to trade-off video quality with the avoidance of stalling. This introduces high latency compared to traditional broadcast methods, mostly in the client buffer which needs to hold enough data to absorb any changes in network conditions. Clients employ an ABR algorithm which monitors network conditions and adjusts the quality at which segments are requested to maximise the user's Quality of Experience. The size of the client buffer depends on the ABR algorithm's capability to respond to changes in network conditions in a timely manner, hence, low latency live streaming requires an ABR algorithm that can perform well with a small client buffer. In this paper, we present Llama - a new ABR algorithm specifically designed to operate in such scenarios. Our new ABR algorithm employs the novel idea of using two independent throughput measurements made over different timescales. We have evaluated Llama by comparing it against four popular ABR algorithms in terms of multiple QoE metrics, across multiple client settings, and in various network scenarios based on CDN logs of a commercial live TV service. Llama outperforms other ABR algorithms, improving the P.1203 Mean Opinion Score (MOS) as well as reducing rebuffering by 33% when using DASH, and 68% with CMAF in the lowest latency scenario.

Despite the Internet being an apex of human achievement for many years, malicious activity and cyber attacks are becoming more prevalent than ever before. Large scale data collection using threat sources such as honeypots have recently been employed to gather information relating to these attacks. While this data naturally details attack properties, there exists challenges in extracting the relevant information from vast data sets to provide valuable insight and a standard description of the attack. Traditionally, threats are identified through the use of signatures that are crafted manually through the composition of IOCs (Indicators of Compromise) extracted from telemetry captured during an attack process, which is often administered by an experienced engineer. These signatures have been proven effective in their use by IDSs (Intrusion Detection Systems) to detect emerging threats. However, little research has been made in automating the extraction of emerging IOCs and the generation of corresponding signatures which incorporate host artefacts. In this paper we present Citrus: a novel approach to the generation of signatures by incorporating host based telemetry extracted from honeypot endpoints. Leveraging this visibility at an endpoint grants a detailed understanding of bleeding edge attack tactics, techniques, and procedures gathered from host logs.

In Named Data Networking (NDN) architectures, a content object is located according to the content’s identifier and can be retrieved from all nodes that hold a replica of the content. The default forwarding strategy of NDN is to forward an Interest packet along the default path from the requester to the server to find a content object according to its name prefix. However, the best path may not be the default path, since content might also be located nearby. Hence, the default strategy could result in a sub-optimal delivery efficiency. To address this issue we introduce a vicinity-based replica finding scheme. This is based on the observation that content objects might be requested several times. Therefore, replicas can be often cached within a particular neighbourhood and thus it might be efficient to specifically look for them in order to improve the content delivery performance. Within this paper, we evaluate the optimal size of the vicinity within which content should be located (i.e. the distance between the requester and its neighbours that are considered within the content search). We also compare the proposed scheme with the default NDN forwarding strategy with respect to replica finding efficiency and network overhead. Using the proposed scheme, we demonstrate that the replica finding mechanism reduces the delivery time effectively with acceptable overhead costs.

The growth in scale and capacity of networks in recent years leads to challenges of positioning and scalability of Intrusion Detection Systems (IDS). With the flexibility afforded by programmable dataplanes, it is now possible to perform a new level of intrusion detection in switches themselves. We present P4ID, combining a rule parser, stateless and stateful packet processing using P4, and evaluate it using publicly available datasets. We show that using this technique, we can achieve a significant reduction in traffic being processed by an IDS.

We propose an intent-based system where, on top of the user intentions, the system itself generates suitable Quality of Service and resilience parameters and may augment the intent characteristics if it detects any room for improvement. We demonstrate the feasibility and challenges of such a system using mininet and the ONOS controller.

Rural communities are often neglected in the rollout of communication infrastructure, delaying or even preventing the delivery of common digital services that are now ubiquitous in modern society. Addressing this technological gap is of paramount importance. In this paper, we analyze the performance of two new and emerging 5G networking technologies, each capable of overcoming some of the challenges present in rural environments. Our analysis is based around a series of deployments of TV White Space (TVWS) and millimetre wave (mm Wave) technologies across rural parts of the UK. These deployments are enhanced with a custom designed monitoring platform that includes adaptive streaming video clients that enable the accurate assessment of end-user quality of experience. Our findings demonstrate that TVWS solutions, which operate on an unlicensed TV band, have clear potential for providing stable broadband services in those areas. Our results also show that although mmWave-based solutions can provide sub-gigabit-speed, they are vulnerable to excessive rainfall and are limited to short line-of-sight usage, making them less applicable to deployment in irregular terrain.

This paper presents an approach to supporting the development process for large-scale smart city applications that leverage edge computing resources. A smart city testbed called CitiFlow is developed, which uses Distributed Node-RED as the underlying middleware to facilitate the decomposition and communication among sub components of large scale smart city applications. For the evaluation, a lab-based setup and a real world deployment were executed and are presented.

When designing Software Defined Networks (SDNs), there is a risk that the additional abstractions available can result in reduced scalability and performance. One such abstraction, intents, are a way in which network administrators can express policies rather than having to define specific forwarding rules. This provides a benefit to administrators in allowing automatic network reconfiguration and fault tolerance. In this paper, we highlight the performance overheads associated with the intents framework from a popular SDN controller, ONOS. We propose a novel prototype that leverages source-based routing and programmable data planes using P4 in order to reduce the overheads of intent-based forwarding

The burden put on network infrastructures is changing. The increasing number of connected devices, along with growing demand, are creating an unsustainable future for the Internet. The recently introduced concept of Fog computing predicts a future Internet where general compute power is ubiquitous, extending the Cloud right the way to the network edge. In turn, this acts as a catalyst for Network Functions Virtualisation (NFV), increasing the potential infrastructure locations for deploying new services, specifically ones that can cater to the demands of the changing Internet. However, current realisations of NFV typically host network functions in homogeneous, centralised servers in Cloud infrastructures. This is in contrast to the Fog where environments are both distributed and heterogeneous, thus current management and orchestration platforms suffer from suboptimal service deployment. With the use of a multiple use cases, and a novel auctioning orchestration method, this paper presents Siren, which is an orchestrator for network functions in the Cloud to Fog continuum.

The emerging network paradigm of Software Defined Networking (SDN) has been increasingly adopted to improve the Quality of Experiences (QoE) across multiple HTTP adaptive streaming (HAS) instances. However, there is currently a gap between research and reality in this field. QoE models, which offer user-level context to network management processes, are often tested in a simulation environment. Such environments do not consider the effects that network protocols, client programs, and other real world factors may have on the outcomes. Ultimately, this can lead to models not functioning as expected in real networks. On the other hand, setting up an experiment that reflects reality is a time consuming process requiring expert knowledge. This paper shares designs and guidelines of an SDN experimentation framework (SDQ), which offers rapid evaluation of QoE models using real network infrastructures.

Network service composition is becoming increasingly flexible, thanks in part to advances in virtualisation and cloud technologies. As these penetrate further into networks, providers are often looking to leverage this infrastructure to improve their service delivery. This desire poses a number of obstacles, including a diversity in device capabilities and the need for a value exchange mechanism. In this demonstration, we present a platform that seeks to address a selection of these challenges.

Network operators recognise that Content Delivery Networks are essential for meeting user Internet application and content demands. The infrastructure must be tightly integrated to provide request routing, content caching, load balancing, scalability and reliability, whilst minimising deployment time and complexity. A major step towards achieving these goals is to embrace recent Software Defined Network and Network Function Virtualisation objectives and design principles. This paper outlines the OpenCache API; an interface used to define the behaviour and operation of an SDN-based content delivery platform in real-time. We demonstrate the applicability and effectiveness of such an API by implementing load-balancing and fail-over functionalities as part of an experimental deployment.

Online video streaming using HTTP Adaptive Streaming (HAS) is becoming the most popular content delivery mechanism for media services. Network and content providers would like to ensure a high degree of video Quality of Experience (QoE) for their end-users. However, traditional network-level metrics do not necessarily reflect the end-users' true perception of delivered content.We introduce an in-network QoE measurement framework (IQMF) that provides QoE monitoring for HAS streams as a service. The framework leverages Software Defined Networking for its control plane functionality to streamline non-intrusive quality monitoring and to offer a closed control loop for QoE-aware service management. IQMF adopts two specifically designed QoE metrics to capture the user experience of HAS streams with respect to video fidelity and switching impact. Finally, we used a pan-European SDN testbed to demonstrate how IQMF can be used as a foundation for in-network QoE measurement and service optimisation.

High quality online video streaming, both live and on-demand, has become an essential part of consumers’ every-day lives. The popularity of video streaming as placed a heavy burden on the network infrastructure that now has to transfer an enormous amount of data very quickly to the end-user. To further exacerbate the situation, the Video-on-Demand (VoD) distribution paradigm uses a unicast independent flow for each user request. This results in multiple duplicate flows carrying the same video assets many times end-to-end. We present OpenCache: a highly configurable, efficient and transparent in-network caching service that aims to improve the VoD distribution efficiency by caching video assets as close to the end-user as possible. OpenCache leverages Software Defined Networking to benefit last mile environments by improving network utilisation and increasing the Quality of Experience for the end-user. Our evaluation on a pan-European OpenFlow testbed uses adaptive video streaming and demonstrates that with the use of OpenCache, the external link utilisation is reduced by 100%. Furthermore the streaming application receives better quality video and observes higher throughput, lower latency and shorter start up and buffering times.

International cooperation on Software-Defined Networking (SDN), crossing the boundaries of Europe, the Americas and Asia, builds a strong foundation for pursuing experimental research through advanced programmable network testbeds. The EU-Japan jointly-funded project FELIX (FEderated Testbeds for Large-scale Infrastructure eXperiments) considers the definition of a common framework for federated Future Internet (FI) testbeds, which are dispersed across continents. This framework will enable an experimenter to (i) request and obtain resources across different testbed infrastructures dynamically; (ii) manage and control the network paths connecting the federated SDN testbed infrastructures; (iii) monitor the underlying resources; and (iv) use distributed applications executed on the federated infrastructures. This paper details six use cases that will be employed to validate the FELIX architecture and software platforms. We present our analysis and end-user considerations, highlighting the necessity to have a global vision of issues within the testbed network. Resource reachability and coherent use of physical connections are key factors in the use cases. This is particularly important when considering the simultaneous use of different technologies such as OpenFlow and the Network Service Interface (NSI) among others.

Efficient content delivery is a constantly evolving challenge on the modern Internet. Reducing the impact of duplicate deliveries of identical content is a key factor in reducing congestion and transit costs for smaller networks. This work leverages SDN concepts and mechanisms in order to transparently store and deliver content from a local cache to the client, thus lightening the load on the WAN and relieving the necessity for urgent network capacity upgrades. An open interface to the cache presents owners with new possibilities for cache control and maintenance. This demonstration showcases a prototype implementation in action on a large-scale OpenFlow testbed deployed across Europe.