227 research outputs found
Implementation and Performance Evaluation of an NGN prototype using WiMax as an Access Technology
Telecommunications networks have evolved to IP-based networks, commonly known as Next Generation Networks (NGN). The biggest challenge in providing high quality realtime multimedia applications is achieving a Quality of Service (QoS) consistent with user expectations. One of the key additional factors affecting QoS is the existence of different QoS mechanisms on the heterogeneous technologies used on NGN platforms. This research investigates the techniques used to achieve consistent QoS on network technologies that use different QoS techniques. Numerous proposals for solving the end-to-end QoS problem in IP networks have adopted policy-based management, use of signalling protocols for communicating applications QoS requirements across different Network Elements and QoS provisioning in Network Elements. Such solutions are dependent on the use of traffic classification and knowledge of the QoS requirements of applications and services on the networks. This research identifies the practical difficulties involved in meeting the QoS requirements of network traffic between WiMax and an IP core network. In the work, a solution based on the concept of class-of-service mapping is proposed. In the proposed solution, QoS is implemented on the two networks and the concept of class-of-service mapping is used to integrate the two QoS systems. This essentially provides consistent QoS to applications as they traverse the two network domains and hence meet end-user QoS expectations. The work is evaluated through a NGN prototype to determine the capabilities of the networks to deliver real-time media that meets user expectations
Optimized IP-CANs to support best charged IMS scenarios
conference paper Published in Personal, Indoor and Mobile Radio Communications, 2009 IEEE 20th International Symposium by IEEE.The pricing and charging mechanisms used in Next
Generation Network (NGN) deployments will influence the profitability
of network operators. NGNs present an opportunity for
the success of service delivery platforms designed for IP multimedia
communications, like the IP Multimedia Subsystem (IMS).
Moreover, they present a platform for the delivery of a multitude
of applications and services to users with different expectations
and budgets. Although usage-based charging schemes are more
meaningful, some recent successful Internet-based applications
and services have attracted widespread usage due to enforcement
of flat-rate pricing. The choice of a pricing scheme often has
a one-to-one relation to the access network technology and the
quality of service guarantee. Flat-rate pricing may easily be
associated with best effort transport. This implies that some
users opt for services without QoS guarantee when favoured by
the pricing methodology. This paper explores scenarios where
services with different QoS requirements available to users with
varying pricing preferences can be provided over a set of IP
connection access networks (IP-CANs) of the IMS.We explore the
use of different pricing schemes for different IP-CANs of the IMS.
We perform testbed evaluations and present results depicting
the income patterns of networks enforcing different pricing and
charging schemes for VoIP and IPTV services. Moreover, we emphasize
the use of simplified pricing schemes on communication
networks.The pricing and charging mechanisms used in Next
Generation Network (NGN) deployments will influence the profitability
of network operators. NGNs present an opportunity for
the success of service delivery platforms designed for IP multimedia
communications, like the IP Multimedia Subsystem (IMS).
Moreover, they present a platform for the delivery of a multitude
of applications and services to users with different expectations
and budgets. Although usage-based charging schemes are more
meaningful, some recent successful Internet-based applications
and services have attracted widespread usage due to enforcement
of flat-rate pricing. The choice of a pricing scheme often has
a one-to-one relation to the access network technology and the
quality of service guarantee. Flat-rate pricing may easily be
associated with best effort transport. This implies that some
users opt for services without QoS guarantee when favoured by
the pricing methodology. This paper explores scenarios where
services with different QoS requirements available to users with
varying pricing preferences can be provided over a set of IP
connection access networks (IP-CANs) of the IMS.We explore the
use of different pricing schemes for different IP-CANs of the IMS.
We perform testbed evaluations and present results depicting
the income patterns of networks enforcing different pricing and
charging schemes for VoIP and IPTV services. Moreover, we emphasize
the use of simplified pricing schemes on communication
networks
User generated content for IMS-based IPTV
Includes abstract.Includes bibliographical references.Web 2.0 services have been on the rise due to improved bandwidth availability. Users can now connect to the internet with a variety of portable devices which are capable of performing multiple tasks. Due to this, services such as Voice over IP (VoIP), presence, social networks, instant messaging (IM) and Internet Protocol television (IPTV) to mention but a few, started to emerge...This thesis proposed a framework that will offer user-generated content on an IMS-Based IPTV and the framework will include a personalised advertising system..
Towards a scalable video interactivity solution over the IMS
Includes bibliographical references (leaves 72-76).Rapid increase in bandwidth and the interactive and scalability features of the Internet provide a precedent for a converged platform that will support interactive television. Next Generation Network platforms such as the IP Multimedia Subsystem (IMS) support Quality of Service (QoS), fair charging and possible integration with other services for the deployment of IPTV services. IMS architecture supports the use of the Session Initiation Protocol (SIP) for session control and the Real Time Streaming Protocol (RTSP) for media control. This study aims to investigate video interactivity designs over the Internet using an evaluation framework to examine the performance of both SIP and RTSP protocols over the IMS over different access networks. It proposes a Three Layered Video Interactivity Framework (TLVIF) to reduce the video processing load on a server
Enabling Layered Video Coding for IMS-Based IPTV Home Services
Nowadays IPTV services are gaining attention from both providers and end users. There is a large effort toward the integration of these services into emerging next-generation network architectures. In particular, one of the most relevant solutions is being proposed by ETSI-TISPAN and is based on the IP multimedia subsystem. This article focuses on introducing layered video coding into TISPAN IMS-based IPTV architecture, allowing cost-effective efficient solutions both for residential users and providers (e.g., flexible support of heterogeneous devices, live mosaics, adaptive video quality based on device and/or network capabilities). The advantages of using layered video coding in the TISPAN IPTV solution are analyzed and illustrated with a set of use cases. Furthermore, this solution has been integrated into a multimedia testbed in order to validate the presented proposal
Options for Securing RTP Sessions
The Real-time Transport Protocol (RTP) is used in a large number of
different application domains and environments. This heterogeneity
implies that different security mechanisms are needed to provide
services such as confidentiality, integrity, and source
authentication of RTP and RTP Control Protocol (RTCP) packets
suitable for the various environments. The range of solutions makes
it difficult for RTP-based application developers to pick the most
suitable mechanism. This document provides an overview of a number
of security solutions for RTP and gives guidance for developers on
how to choose the appropriate security mechanism
Supporting mobility in an IMS-based P2P IPTV service: A proactive context transfer mechanism
In recent years, IPTV has received an increasing amount of interest from the industry, commercial providers and the research community, alike. In this context, standardization bodies, such as ETSI and ITU-T, are specifying the architecture of IPTV systems based on IP multicast. An interesting alternative to support the IPTV service delivery relies on the Peer-to-Peer (P2P) paradigm to distribute and push the streaming effort towards the network edge. However, while P2P IPTV was studied in fixed access technologies, there has been little attention paid to the implications arising in mobile environments. One of these involves the service handover when the user moves to a different network. By analyzing previous work from the perspective of an IPTV service, we concluded that a proactive approach is necessary for the handling of inter-network handovers. In this paper, we propose a new general handover mechanism for the IP Multimedia Subsystem (IMS), while studying its applicability to a P2P IPTV service. Our solution, called proactive context transfer service, incorporates the existing IEEE 802.21 technology in order to minimize the handover delay. The proposal is validated by comparing it against solutions derived from previous work.This article has been partially granted by the Spanish MEC
through the CONPARTE project (TEC2007–67966-C03–03/TCM)
and by the Madrid Community through the MEDIANET project
(S-2009/TIC-1468).Publicad
Route selection impacts on achieving enhanced IMS QoS
ArticleThe different planes in the IMS interact via specific
reference points to deliver multimedia services to the user. QoS
provisioning for IMS communications has been standardized for
access networks only, with the assumption of an over provisioned
IP core. Effective provisioning of multimedia services requires
performance guarantee along the complete path of the sessions.
End-to-end QoS in IP networks is affected by the route traversed
by the user traffic. Moreover QoS guarantees in one ISP domain
are not effective for transit traffic exiting the domain. QoS
extensions to exterior gateway routing protocols have been
proposed to transfer route QoS information beyond one
autonomous system (domain). This paper explores options for
mapping inter-domain QoS information learnt on the media plane
into control plane session information for IMS QoS control.
Through testbed evaluations we show the effect of routing on delays
experienced in IMS communications.The different planes in the IMS interact via specific
reference points to deliver multimedia services to the user. QoS
provisioning for IMS communications has been standardized for
access networks only, with the assumption of an over provisioned
IP core. Effective provisioning of multimedia services requires
performance guarantee along the complete path of the sessions.
End-to-end QoS in IP networks is affected by the route traversed
by the user traffic. Moreover QoS guarantees in one ISP domain
are not effective for transit traffic exiting the domain. QoS
extensions to exterior gateway routing protocols have been
proposed to transfer route QoS information beyond one
autonomous system (domain). This paper explores options for
mapping inter-domain QoS information learnt on the media plane
into control plane session information for IMS QoS control.
Through testbed evaluations we show the effect of routing on delays
experienced in IMS communications
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