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Multimedia communication in the Internet shows evolution from SIP-based to WebRTC architecture which is also related to migration of QoS solutions from RSVP-based to DiffServ-based, supported also in IEEE 802.11. In order to figure out... more
Multimedia communication in the Internet shows evolution from SIP-based to WebRTC architecture which is also related to migration of QoS solutions from RSVP-based to DiffServ-based, supported also in IEEE 802.11. In order to figure out the efficiency of WEbRTC implementation in mobile network, the QoS parameters were used: throughput of media streams, error rate, delay and jitter. During experiments, 4K video streams were transmitted with the use of WebRTC technology via an IEEE 802.11ac network. The results of the experiments were compared with the ones obtained for non-responsive (not congestion controlled) UDP streams. WebRTC transmissions were live transmissions from a web camera, and UDP transmissions were emulated with the use of the iPerf tool. Results of the comparative analysis show that if the total throughput of simultaneously transmitted video streams exceeds the available throughput of the wireless link, the WebRTC is able to scale down the transmitted stream to preserve the real-time character of the stream and significantly reduce the error rate. As a result, the observed bit error rate achieved by the WebRTC was about three orders of magnitude lower than the bit error rate of non-responsive UDP streams. However, this improvement of the quality of service of the WebRTC media streams is at a cost of quality of experience (lower frame rate).
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WebRTC uses two simulcast schemes: the older, based on the replication of streams encoded to different qualities of the original signal (typically: video), and the newer, fully introduced this year to one of the more popular browsers,... more
WebRTC uses two simulcast schemes: the older, based on the replication of streams encoded to different qualities of the original signal (typically: video), and the newer, fully introduced this year to one of the more popular browsers, based on layered encoding. While the first solution has a well-established position in the WebRTC technology, the layered simulcast still remains in an early stage of development. The goal of this paper was to compare behavior of the two WebRTC simulcast schemes in terms of the key feature of the simulcast, i.e. its adaptability to network conditions. To achieve this goal, we wrote the WebRTC application (a simple videomonitoring software) that act as simulcast sender. The adaptability of the simulcast schemes was investigated for the case of video traffic transmitted in a heterogeneous test network (wired and wireless). As adaptability indicators, such as the throughput and packet error rate were used. Results of the simulcasting of 4K video show that in the case of infrastructural limitations only there are no significant differences between the adaptability of the stream replication simulcast and the layered simulcast. Adaptability for dynamic limitations (introduced by background traffic) was better in the case of the layered simulcast.
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Research Interests: Computer Science, Telecommunications, Broadband, Computer Network, Broadband Networks, and 13 moreEconomic analysis, Wireless, Optical, Wireless Broadband, Technology and Engineering, Wireless Access Network Deployment Strategy, Broadband Access, CapEx, Capital Expenditure, Software Deployment, Optical Wireless, Opex, and Access Network
In this paper we propose a flying IoT system designed to monitor parking lot. The system is composed of a flying mobile station and a terrestrial station. The mobile station consists of visual monitoring camera associated with air quality... more
In this paper we propose a flying IoT system designed to monitor parking lot. The system is composed of a flying mobile station and a terrestrial station. The mobile station consists of visual monitoring camera associated with air quality monitoring sensors, mounted on a Turnigy SK450 quad copter controlled with Pixhawk autopilot hardware. Data gathered from the monitoring system are transmitted to an IoT broker running on a Raspberry Pi 3+ microcontroller, also mounted on a drone, that aggregates data into a common flow and retransmits them to the terrestrial station. The transmission system was build according to WebRTC architecture. In order to assure separation of the production network (for transmission of application data) and the management network (for management and control purposes), two different transmission channels are used: one for the WebRTC transmission and the other for controlling the drone. The paper includes a description of the system and the results of field trials carried out on the parking lot of the AGH University of technology.
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This paper is devoted to analysis of QoS parameters of WebRTC traffic presented for centralized videoconferencing system used for collaborative work. This system consists of a videoconference application, built according to the WebRTC... more
This paper is devoted to analysis of QoS parameters of WebRTC traffic presented for centralized videoconferencing system used for collaborative work. This system consists of a videoconference application, built according to the WebRTC architecture, and a telemetric system, built as the IoT environment. Tests were carried out for three locations of the conference bridge: in private cloud (the OpenStack cloud), in public cloud (the AWS cloud) and in local network. Results show, that conference bridge in a cloud is a good solution for the WebRTC, and additional transmission of telemetric data do not affect the QoS parameters of WebRTC's media stream
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Research Interests: Physics()
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Deployment of PCE (Path Computation Element) architecture in high-speed MPLS/GMPLS networks is at present widely accepted and helps to run path setup operations for applications with explicitly defined objective functions and also with... more
Deployment of PCE (Path Computation Element) architecture in high-speed MPLS/GMPLS networks is at present widely accepted and helps to run path setup operations for applications with explicitly defined objective functions and also with QoS requirements. The paper reports on recent research investigations with PCE-based path computation employing 3-layer traffic engineering (TE) system: PCE module equipped with IBM Cplex LP solver is used in the highest layer, SDN controller in the intermediate layer responsible for transferring path setup requests towards virtual routers in the lowest layer. Presented results show usefulness of PCE architecture with SDN controller and applicability of bandwidth-oriented optimization with objective functions.
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In this paper we propose a flying IoT system designed to monitor parking lot. The system is composed of a flying mobile station and a terrestrial station. The mobile station consists of visual monitoring camera associated with air quality... more
In this paper we propose a flying IoT system designed to monitor parking lot. The system is composed of a flying mobile station and a terrestrial station. The mobile station consists of visual monitoring camera associated with air quality monitoring sensors, mounted on a Turnigy SK450 quad copter controlled with Pixhawk autopilot hardware. Data gathered from the monitoring system are transmitted to an IoT broker running on a Raspberry Pi 3+ microcontroller, also mounted on a drone, that aggregates data into a common flow and retransmits them to the terrestrial station. The transmission system was build according to WebRTC architecture. In order to assure separation of the production network (for transmission of application data) and the management network (for management and control purposes), two different transmission channels are used: one for the WebRTC transmission and the other for controlling the drone. The paper includes a description of the system and the results of field trials carried out on the parking lot of the AGH University of technology.
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When dynamic service interconnection requests are managed by a centralized system (e.g., a network management system - NMS), the time required for the connections to be fully operational might be heavily impacted by the policy utilized to... more
When dynamic service interconnection requests are managed by a centralized system (e.g., a network management system - NMS), the time required for the connections to be fully operational might be heavily impacted by the policy utilized to serve them. The policies must be devised for mitigating issues that increase this time, such as commercial router irresponsiveness to configuration commands during
Research Interests: Computer Science, Computer Architecture, Distributed Computing, Grid Computing, Computer Networks, and 11 moreTechnology Management, Computer Network, Quality of Service, Experimental Evaluation, Grid, Provisioning, Router, Interconnection, High Performance Switching and Routing, service Business, and Network Management System
In this study the design of reliable network topologies is applied to a typical metro network scenario. Results show that, with an increasing amount of traffic, ring topologies represent a less attractive solution and, on the other hand,... more
In this study the design of reliable network topologies is applied to a typical metro network scenario. Results show that, with an increasing amount of traffic, ring topologies represent a less attractive solution and, on the other hand, highly connected DWDM mesh networks are required to grant the required level of throughput for bandwidth demanding applications and services.
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If dynamic bandwidth-guaranteed connections between distributed services (e.g., grid services) are provisioned through a centralized system, the policy to serve connection requests might heavily impact both the success in and the time... more
If dynamic bandwidth-guaranteed connections between distributed services (e.g., grid services) are provisioned through a centralized system, the policy to serve connection requests might heavily impact both the success in and the time required for setting up user services (e.g., grid-enabled applications). In this paper, the implementation of a batch queue in the centralized system is proposed. By implementing different service
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Context plays a significant role in the generation of motion for dynamic agents in interactive environments. This work proposes a modular method that utilises a model of the environment to aid motion prediction of tracked agents. This... more
Context plays a significant role in the generation of motion for dynamic agents in interactive environments. This work proposes a modular method that utilises a model of the environment to aid motion prediction of tracked agents. This paper shows that modelling the spatial and dynamic aspects of a given environment alongside the local per agent behaviour results in more accurate and informed long-term motion prediction. Further, we observe that this decoupling of dynamics and environment models allows for better generalisation to unseen environments, requiring that only a spatial representation of a new environment be learned. We highlight the model's prediction capability using a benchmark pedestrian tracking problem and by tracking a robot arm performing a tabletop manipulation task. The proposed approach allows for robust and data efficient forward modelling, and relaxes the need for full model re-training in new environments. We evaluate this through an ablation study which ...
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The paper provides an overview of the resilient schemes currently adopted in network architectures based on IP over Automatically Switched Optical Networks (ASONs)/Generalized Multiprotocol Label Switching (GMPLS) based optical networks,... more
The paper provides an overview of the resilient schemes currently adopted in network architectures based on IP over Automatically Switched Optical Networks (ASONs)/Generalized Multiprotocol Label Switching (GMPLS) based optical networks, namely the Optical Internet. In addition it outlooks the raising challenges and possible solutions in implementing advanced resilient schemes capable of satisfying the requirements of the different applications carried by a single multi-layer network infrastructure.
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This paper deals with the fundamentals and current standardization efforts for IEEE 802.17 RPR (Resilient Packet Ring). Its special resilience features make this technology robust against outages of the network infrastructure. The goals... more
This paper deals with the fundamentals and current standardization efforts for IEEE 802.17 RPR (Resilient Packet Ring). Its special resilience features make this technology robust against outages of the network infrastructure. The goals of this paper are threefold. Firstly, the fundamentals of RPR and the standardization process carried out under the auspices of IEEE and ITU are overviewed. Secondly, potentially hazardous situations involving traffic assignments are defined and illustrated. Finally, possible situations where simplicity, enhanced throughput and automatic resilience features of RPR may be advantageous for network operators are identified. 1.
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Multimedia communication in the Internet shows evolution from SIP-based to WebRTC architecture which is also related to migration of QoS solutions from RSVP-based to DiffServ-based, supported also in IEEE 802.11. In order to figure out... more
Multimedia communication in the Internet shows evolution from SIP-based to WebRTC architecture which is also related to migration of QoS solutions from RSVP-based to DiffServ-based, supported also in IEEE 802.11. In order to figure out the efficiency of WEbRTC implementation in mobile network, the QoS parameters were used: throughput of media streams, error rate, delay and jitter. During experiments, 4K video streams were transmitted with the use of WebRTC technology via an IEEE 802.11ac network. The results of the experiments were compared with the ones obtained for non-responsive (not congestion controlled) UDP streams. WebRTC transmissions were live transmissions from a web camera, and UDP transmissions were emulated with the use of the iPerf tool. Results of the comparative analysis show that if the total throughput of simultaneously transmitted video streams exceeds the available throughput of the wireless link, the WebRTC is able to scale down the transmitted stream to preserv...
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The paper describes fundamental features of RPR (Resilient Packet Ring- IEEE 802.17 standard). It focuses on proposals how to improve fairness mechanism and to increase network efficiency in state of congestion. Recovery mechanisms are... more
The paper describes fundamental features of RPR (Resilient Packet Ring- IEEE 802.17 standard). It focuses on proposals how to improve fairness mechanism and to increase network efficiency in state of congestion. Recovery mechanisms are also discussed, with presented analytical and simulation results. The goals of paper are threefold. At first, we show RPR main features and describe its current status. Secondly, we present main recovery and resilience features of RPR and propose solutions for improving both fairness and congestion control. Finally, a new concept, the enhanced hold-off timer (EHOT) is introduced improving recovery actions in multilayer networks. Some simulation results are presented in order to illustrate advantages of proposed solution.
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In this paper the authors intend to report results for performance evaluation of Xen-based node providing both transport and computational functionalities. This node design is proposed as the implementation platform developed for the... more
In this paper the authors intend to report results for performance evaluation of Xen-based node providing both transport and computational functionalities. This node design is proposed as the implementation platform developed for the Polish Initiative of Future Internet called System IIP. In particular, we search for mutual dependence among transport and computational performance parameters of the node. Our investigations show that there is significant dependence among performance indices, such as virtual link bandwidth and node’s processing power, strongly depending on frame size. The tests and measurements were done according to fundamental methodology designed for network devices, described in RFC 2544. The goal of those investigations is to design a provisioning module allocating both transport and computational resources. Keywords—benchmarking, Future Internet, measurements, virtualization, Xen.
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The paper describes fundamental features of RPR (Resilient Packet Ring - IEEE 802.17 standard). It focuses on proposals how to improve fairness mechanism and to increase network efficiency in state of congestion. Recovery mechanisms are... more
The paper describes fundamental features of RPR (Resilient Packet Ring - IEEE 802.17 standard). It focuses on proposals how to improve fairness mechanism and to increase network efficiency in state of congestion. Recovery mechanisms are also discussed, with presented analytical and simulation results. The goals of paper are threefold. At first, we show RPR main features and describe its current status. Secondly, we present main recovery and resilience features of RPR and propose solutions for improving both fairness and congestion control. Finally, a new concept, the enhanced hold-off timer (EHOT) is introduced improving recovery actions in multilayer networks. Some simulation results are presented in order to illustrate advantages of proposed solution.
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We demonstrate tests of a flow-based router enhanced with the additional mechanisms: Emergency Connections, Efficient Congestion Control, Global Protected Flow List and Per-User Fairness. The tests were conducted in the Click environment.... more
We demonstrate tests of a flow-based router enhanced with the additional mechanisms: Emergency Connections, Efficient Congestion Control, Global Protected Flow List and Per-User Fairness. The tests were conducted in the Click environment. The analyzed mechanisms allow for immediate acceptance of high priority traffic, protection of streaming flows in congestion, and ensure high reliability and fairness. In this paper, we show that these mechanisms work successfully in a laboratory network. Moreover, they all work at the same time providing high-level coordinated performance. Test results show significant advantages of the cross-protect router architecture over standard IP routers in several areas.
ATM network is a flexible environment to provide efficient transport of multimedia traffic. MPEG-encoded video information constitutes significant amount of transmitted data in broadband network. The paper investigates a gain which can be... more
ATM network is a flexible environment to provide efficient transport of multimedia traffic. MPEG-encoded video information constitutes significant amount of transmitted data in broadband network. The paper investigates a gain which can be obtained when using results of statistical studies on stored MPEG files. Performance of transfer of MPEG information via CBR and rt-VBR links is studied.
Overlay applications are generating the most of the traffic in today's Internet. Therefore, ISPs have to consider the optimization of this traffic and its associated operational costs. This paper presents the approach of the SmoothIT... more
Overlay applications are generating the most of the traffic in today's Internet. Therefore, ISPs have to consider the optimization of this traffic and its associated operational costs. This paper presents the approach of the SmoothIT project to improve the end users' QoE and to reduce the ISPs costs. This approach is based on the specification of Economic Traffic Management mechanisms that are implemented in the “SmoothIT Information Service” architecture. This architecture can take advantage of the usage of NGN transport control functionalities, providing improved QoE to the end users of the overlay applications.