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A Framework for Multiaccess Support for Unreliable Internet Traffic using Multipath DCCP
Mobile nodes are typically equipped with multiple radios and can connect to multiple radio access networks (e.g. WiFi, LTE and 5G). Consequently, it is important to design mechanisms that efficiently manage multiple network interfaces for aggregating the capacity, steering of traffic flows or switching flows among multiple interfaces. While such multi-access solutions have the potential to increase the overall traffic throughput and communication reliability, the variable latencies on different access links introduce packet delay variation which has negative effect on the application quality of service and user quality of experience. In this paper, we present a new IP-compatible multipath framework for heterogeneous access networks. The framework uses Multipath Datagram Congestion Control Protocol (MP-DCCP) - a set of extensions to regular DCCP - to enable a transport connection to operate across multiple access networks, simultaneously. We present the design of the new protocol framework and show simulation and experimental testbed results that (1) demonstrate the operation of the new framework, and (2) demonstrate the ability of our solution to manage significant packet delay variation caused by the asymmetry of network paths, by applying pluggable packet scheduling or reordering algorithms
Reconfigurable media coding: a new specification model for multimedia coders
Multimedia coding technology, after about 20 years of active research, has delivered a rich variety of different and complex coding algorithms. Selecting an appropriate subset of these algorithms would, in principle, enable a designer to produce the codec supporting any desired functionality as well as any desired trade-off between compression performance and implementation complexity. Currently, interoperability demands that this selection process be hard-wired into the normative descriptions of the codec, or at a lower level, into a predefined number of choices, known as profiles, codified within each standard specification. This paper presents an alternative paradigm for codec deployment that is currently under development by MPEG, known as Reconfigurable Media Coding (RMC). Using the RMC framework, arbitrary combinations of fundamental algorithms may be assembled, without predefined standardization, because everything necessary for specifying the decoding process is delivered alongside the content itself. This side-information consists of a description of the bitstream syntax, as well as a description of the decoder configuration. Decoder configuration information is provided as a description of the interconnections between algorithmic blocks. The approach has been validated by development of an RMC format that matches MPEG-4 Video, and then extending the format by adding new chroma-subsampling patterns
Reconfigurable Video Coding on multicore : an overview of its main objectives
International audienceThe current monolithic and lengthy scheme behind the standardization and the design of new video coding standards is becoming inappropriate to satisfy the dynamism and changing needs of the video coding community. Such scheme and specification formalism does not allow the clear commonalities between the different codecs to be shown, at the level of the specification nor at the level of the implementation. Such a problem is one of the main reasons for the typically long interval elapsing between the time a new idea is validated until it is implemented in consumer products as part of a worldwide standard. The analysis of this problem originated a new standard initiative within the International Organization for Standardization (ISO)/ International Electrotechnical Commission (IEC) Moving Pictures Experts Group (MPEG) committee, namely Reconfigurable Video Coding (RVC). The main idea is to develop a video coding standard that overcomes many shortcomings of the current standardization and specification process by updating and progressively incrementing a modular library of components. As the name implies, flexibility and reconfigurability are new attractive features of the RVC standard. Besides allowing for the definition of new codec algorithms, such features, as well as the dataflow-based specification formalism, open the way to define video coding standards that expressly target implementations on platforms with multiple cores. This article provides an overview of the main objectives of the new RVC standard, with an emphasis on the features that enable efficient implementation on platforms with multiple cores. A brief introduction to the methodologies that efficiently map RVC codec specifications to multicore platforms is accompanied with an example of the possible breakthroughs that are expected to occur in the design and deployment of multimedia services on multicore platforms
Ubiquitous Integration and Temporal Synchronisation (UbilTS) framework : a solution for building complex multimodal data capture and interactive systems
Contemporary Data Capture and Interactive Systems (DCIS) systems are tied in with various
technical complexities such as multimodal data types, diverse hardware and software
components, time synchronisation issues and distributed deployment configurations. Building
these systems is inherently difficult and requires addressing of these complexities before the
intended and purposeful functionalities can be attained. The technical issues are often
common and similar among diverse applications.
This thesis presents the Ubiquitous Integration and Temporal Synchronisation (UbiITS)
framework, a generic solution to address the technical complexities in building DCISs. The
proposed solution is an abstract software framework that can be extended and customised to
any application requirements. UbiITS includes all fundamental software components,
techniques, system level layer abstractions and reference architecture as a collection to enable
the systematic construction of complex DCISs.
This work details four case studies to showcase the versatility and extensibility of UbiITS
framework’s functionalities and demonstrate how it was employed to successfully solve a
range of technical requirements. In each case UbiITS operated as the core element of each
application. Additionally, these case studies are novel systems by themselves in each of their
domains. Longstanding technical issues such as flexibly integrating and interoperating
multimodal tools, precise time synchronisation, etc., were resolved in each application by
employing UbiITS. The framework enabled establishing a functional system infrastructure in
these cases, essentially opening up new lines of research in each discipline where these
research approaches would not have been possible without the infrastructure provided by the
framework. The thesis further presents a sample implementation of the framework on a
device firmware exhibiting its capability to be directly implemented on a hardware platform.
Summary metrics are also produced to establish the complexity, reusability, extendibility,
implementation and maintainability characteristics of the framework.Engineering and Physical Sciences Research Council (EPSRC) grants - EP/F02553X/1, 114433 and 11394
Towards a Scalable Hardware/Software Co-Design Platform for Real-time Pedestrian Tracking Based on a ZYNQ-7000 Device
Currently, most designers face a daunting task to
research different design flows and learn the intricacies of
specific software from various manufacturers in
hardware/software co-design. An urgent need of creating a
scalable hardware/software co-design platform has become a key
strategic element for developing hardware/software integrated
systems. In this paper, we propose a new design flow for building
a scalable co-design platform on FPGA-based system-on-chip.
We employ an integrated approach to implement a histogram
oriented gradients (HOG) and a support vector machine (SVM)
classification on a programmable device for pedestrian tracking.
Not only was hardware resource analysis reported, but the
precision and success rates of pedestrian tracking on nine open
access image data sets are also analysed. Finally, our proposed
design flow can be used for any real-time image processingrelated
products on programmable ZYNQ-based embedded
systems, which benefits from a reduced design time and provide a
scalable solution for embedded image processing products
Real‐time interactive social environments: A review of BT's generic learning platform
Online learning in particular and lifelong learning in general require a learning platform that makes sense both pedagogically and commercially. This paper sets out to describe what we mean by generic, learning and platform. The technical requirements are described, and various trials that test the technical, educational and commercial nature of the platform are described Finally, the future developments planned for the Real‐time Interactive Social Environments (RISE) are discusse
Run-time monitoring approach for the shark kernel
Typically common embedded systems are designed with
high resource constraints. Static designs are often chosen
to address very specific use cases. On contrast, a dynamic
design must be used if the system must supply a real-time
service where the input may contain factors of
indeterminism. Thus, adding new functionality on these
systems is often accomplished by higher development
time, tests and costs, since new functionality push the
system complexity and dynamics to a higher level.
Usually, these systems have to adapt themselves to
evolving requirements and changing service requests. In
this perspective, run-time monitoring of the system
behaviour becomes an important requirement, allowing to
dynamically capturing the actual scheduling progress and
resource utilization. For this to succeed, operating
systems need to expose their internal behaviour and state,
making it available to the external applications, usually
using a run-time monitoring mechanism. However, such
mechanism can impose a burden in the system itself if not
wisely used. In this paper we explore this problem and
propose a framework, which is intended to provide this
run-time mechanism whilst achieving code separation,
run-time efficiency and flexibility for the final developer
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