Socrates Varakliotis

Transport of MPEG—4 over IP/RTP

In this paper we review and discuss some of the current efforts and proposals in the standardization bodies IETF and MPEG for the delivery of MPEG—4 over IP. We address the issues of payload format and media control by describing two architectures that allow for MPEC—4 streaming. Finally, we describe some MPEG—4 over IP streaming experiments in which the RTP MPEG—4 payload format is used in conjunction with per—stream Forward Error Correction support, in presence of packet loss.

IPv6 Addressing Proxy: Mapping Native Addressing from Legacy Technologies and Devices to the Internet of Things (IPv6)

Sensors utilize a large number of heterogeneous technologies for a varied set of application environments. The sheer number of devices involved requires that this Internet be the Future Internet, with a core network based on IPv6 and a higher scalability in order to be able to address all the devices, sensors and things located around us. This capability to connect through IPv6 devices, sensors and things is what is defining the so-called Internet of Things (IoT). IPv6 provides addressing space to reach this ubiquitous set of sensors, but legacy technologies, such as X10, European Installation Bus (EIB), Controller Area Network (CAN) and radio frequency ID (RFID) from the industrial, home automation and logistic application areas, do not support the IPv6 protocol. For that reason, a technique must be devised to map the sensor and identification technologies to IPv6, thus allowing homogeneous access via IPv6 features in the context of the IoT. This paper proposes a mapping between the native addressing of each technology and an IPv6 address following a set of rules that are discussed and proposed in this work. Specifically, the paper presents a technology-dependent IPv6 addressing proxy, which maps each device to the different subnetworks built under the IPv6 prefix addresses provided by the internet service provider for each home, building or user. The IPv6 addressing proxy offers a common addressing environment based on IPv6 for all the devices, regardless of the device technology. Thereby, this offers a scalable and homogeneous solution to interact with devices that do not support IPv6 addressing. The IPv6 addressing proxy has been implemented in a multi-protocol card and evaluated successfully its performance, scalability and interoperability through a protocol built over IPv6.

Extending the Internet of Things to the Future Internet through IPv6 support

Emerging Internet of Things IoT/Machine-to-Machine M2M systems require a transparent access to information and services through a seamless integration into the Future Internet. This integration exploits infrastructure and services found on the Internet by the IoT. On the one hand, the so-called Web of Things aims for direct Web connectivity by pushing its technology down to devices and smart things. On the other hand, the current and Future Internet offer stable, scalable, extensive, and tested protocols for node and service discovery, mobility, security, and auto-configuration, which are also required for the IoT. In order to integrate the IoT into the Internet, this work adapts, extends, and bridges using IPv6 the existing IoT building blocks such as solutions from IEEE 802.15.4, BT-LE, RFID while maintaining backwards compatibility with legacy networked embedded systems from building and industrial automation. Specifically, this work presents an extended Internet stack with a set of adaptation layers from non-IP towards the IPv6-based network layer in order to enable homogeneous access for applications and services.

Coding of animated 3-D wireframe models for internet streaming applications

In this paper we present a coding technique for 3-D animated wireframe models, suitable for Internet streaming. First we present the MPEG-4 like coding scheme with simple RTP packetisation, and provide details of the achieved compression efficiency. Then, we describe a distortion metric for such a signal and we conduct experiments to study the effect of packet loss, following a bursty packet loss model that approximates a simulated IP network. Our experiments examine the performance of the coding scheme for a simple streaming scenario with different sequence configurations. The results show that short-term and short average length burst losses of up to 30% have a logarithmic effect on the decrease of the animation smoothness in the case of simple differential coding. This logarithmic decrease is corrected to linear by inserting I-frames to the sequence at the expense of reduced compression. The result is smoother animation.

Transport of MPEG-4 over IP/RTP

The goal of the article is twofold. First, we overview some of the issues related to the transport of MPEG-4 content over IP/RTP and in particular we discuss the IETF MPEG-4 payload format for SL-packetized streams. We then present the experimental results we obtained with our implementation and additional support of per-stream parity forward error correction.

Optimally smooth error resilient streaming of 3D wireframe animations

Much research has been undertaken in the area of streaming video across computer networks in general and the Internet in particular, but relatively little has been undertaken in the field of streaming 3-D wireframe animation. Despite superficial similarities, both being visual media, the two are significantly different. Different data passes across the network so loss affects signal reconstruction differently. Regrettably, the perceptual effects of such loss have been poorly addressed in the context of animation to date and much of the work that there has been in this field has relied on objective measures such as PSNR in lieu of those that take subjective effects into account. In this paper, we bring together concepts from a number of fields to address the problem of how to achieve optimal resilience to errors in terms of the perceptual effect at the receiver. To achieve this, we partition the animation stream into a number of layers and apply Reed-Solomon (RS) forward error correction (FEC) codes to each layer independently and in such a way as to maintain the same overall bitrate whilst minimizing the perceptual effects of error, as measured by a distortion metric derived from related work in the area of static 3-D mesh compression. Experimental results show the efficacy of our proposed scheme under varying network bandwidth and loss conditions for different layer partitionings. The results indicate that with the proposed Unequal Error Protection (UEP) combined with Error Concealment (EC) and efficient packetization scheme, we can achieve graceful degradation of streamed animations at higher packet loss rates than other approaches that do not cater for the visual importance of the layers and use only objective layering metrics. Our experiments also demonstrate how to tune the packetization parameters in order to achieve efficient layering with respect to the subjective metric of surface smoothness.

Developing and Evaluating JIApp: Acceptability and Usability of a Smartphone App System to Improve Self-Management in Young People With Juvenile Idiopathic Arthritis

Background Flare-ups in juvenile idiopathic arthritis (JIA) are characterized by joint pain and swelling and often accompanied with fatigue, negative emotions, and reduced participation in activities. To minimize the impact of JIA on the physical and psychosocial development and well-being of young people (YP), it is essential to regularly monitor disease activity and side effects, as well as to support self-management such as adherence to treatment plans and engagement in general health-promoting behaviors. Smartphone technology has the potential to engage YP with their health care through convenient self-monitoring and easy access to information. In addition, having a more accurate summary of self-reported fluctuations in symptoms, behaviors, and psychosocial problems can help both YP and health care professionals (HCPs) better understand the patient’s condition, identify barriers to self-management, and assess treatment effectiveness and additional health care needs. No comprehensive smartphone app has yet been developed in collaboration with YP with JIA, their parents, and HCPs involved in their care. Objectives The objective of this study was to design, develop, and evaluate the acceptability and usability of JIApp, a self-management smartphone app system for YP with JIA and HCPs. Methods We used a qualitative, user-centered design approach involving YP, parents, and HCPs from the rheumatology team. The study was conducted in three phases: (1) phase I focused on developing consensus on the features, content, and design of the app; (2) phase II was used for further refining and evaluating the app prototype; and (3) phase III focused on usability testing of the app. The interview transcripts were analyzed using qualitative content analysis. Results A total of 29 YP (aged 10-23, median age 17) with JIA, 7 parents, and 21 HCPs were interviewed. Major themes identified as the ones that helped inform app development in phase I were: (1) remote monitoring of symptoms, well-being, and activities; (2) treatment adherence; and (3) education and support. During phase II, three more themes emerged that informed further refinement of the app prototype. These included (4) adapting a reward system to motivate end users for using the app; (5) design of the app interface; and (6) clinical practice integration. The usability testing during phase III demonstrated high rates of overall satisfaction and further affirmed the content validity of the app. Conclusions We present the development and evaluation of a smartphone app to encourage self-management and engagement with health care for YP with JIA. The app was found to have high levels of acceptability and usability among YP and HCPs and has the potential to improve health care and outcomes for this age group. Future feasibility testing in a prospective study will firmly establish the reliability, efficacy, and cost-effectiveness of such an app intervention for patients with arthritis.

Transport Layer Multipath on Wireless Sensor Network Backhaul Links

With the increasing popularity of wireless sensor networks in hostile environments it would be desirable to have more reliable ways of delivering collected information to its destination. With a common scenario involving nodes in a sensor network relaying data back to a gateway or router device, which is connected to a backhaul network, the question arises whether this single point of failure could not be improved, especially in those cases where mobile networks are involved (e.g. Personal or Vehicle Area Networks). This paper demonstrates how this single point of failure can be improved upon in regards to network failures. The suggested novel approach consists of bundling multiple connections at the transport layer on the gateway to improve the reliability by employing redundancy. It also has a number of further advantages such as helping to reduce the delay in sensor network mobility scenarios by cutting back on handover delays and offering alternate paths for retransmissions. In the past, multipath research in wireless sensor networks has largely focused on the data link, or network layer. We endeavour to show that there are also reasons to employ it at the transport layer in certain situations.

Open Multi-Purpose Gateway for Emergency Services Internetworking

Access to a variety of Networks will be a central part of technologies employed by future emergency responders. Incompatibilities are often introduced as a result of widely disparate uses and varying capabilities of devices, which must be resolved through internetworking. This requires devices such as gateways to connect these networks and enable communication to the furthest extent possible.This paper outlines a number of specific cases in which gateways may be used as well as the capabilities different available devices offer and how they can be used for multiple purposes in an Emergency Services context.

The use of Handle to aid IoT security

This paper describes how the use of Identifiers with an appropriate system of identifier storage, registration and identifier resolution can greatly extend the flexibility of a system dealing with IoT. The features of the CNRI Handle system are shown to match well the requirements of such a IoT system. We have validated our thesis, by applying the system to a smart office environment, and shown how the properties of the IoT devices can be stored securely in a Handle repository including the characteristics of the device, network addresses and security attributes. We have concentrated on the security functionality combined with IPv6 infrastructure and the relevant Internet protocols.