243 research outputs found
Multicast source mobility support for regenerative satellite networks
YesSatellite communications provides an effective solution to the ever increasing demand for mobile and ubiquitous communications especially in areas where terrestrial communication infrastructure is not present. IP multicasting is a bandwidth saving technology which could become an indispensable means of group communication over satellites since it can utilise the scarce and expensive satellite resources in an efficient way. In Source-Specific Multicast (SSM) the data is sent through a multicast tree from the source to all the receivers. However, if a source is a mobile node moving from one network to another, then special mechanisms are required to make sure this multicast tree does not break. Until now, while many research efforts have been made to provide IP multicast for the mobile nodes, they are mainly focused on terrestrial networks. Unfortunately, the terrestrial mobile multicast schemes are not directly applicable in a satellite environment. This paper, proposes a new mechanism to support multicast source mobility in SSM based applications for a mesh multi-beam satellite network with receivers both within the satellite network and in the Internet. In the proposed mechanism, the SSM receivers continue to receive multicast traffic from the mobile source despite the fact that the IP address of the source keeps on changing as it changes its point of attachment from one satellite gateway (GW) to another. The proposed scheme is evaluated and the results compared with the mobile IP home subscription (MIP HS)-based approach. The results show that the proposed scheme outperforms the MIP HS-based approach in terms of signalling cost and packet delivery cost
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
Roaming Real-Time Applications - Mobility Services in IPv6 Networks
Emerging mobility standards within the next generation Internet Protocol,
IPv6, promise to continuously operate devices roaming between IP networks.
Associated with the paradigm of ubiquitous computing and communication, network
technology is on the spot to deliver voice and videoconferencing as a standard
internet solution. However, current roaming procedures are too slow, to remain
seamless for real-time applications. Multicast mobility still waits for a
convincing design. This paper investigates the temporal behaviour of mobile
IPv6 with dedicated focus on topological impacts. Extending the hierarchical
mobile IPv6 approach we suggest protocol improvements for a continuous
handover, which may serve bidirectional multicast communication, as well. Along
this line a multicast mobility concept is introduced as a service for clients
and sources, as they are of dedicated importance in multipoint conferencing
applications. The mechanisms introduced do not rely on assumptions of any
specific multicast routing protocol in use.Comment: 15 pages, 5 figure
Reflections on security options for the real-time transport protocol framework
The Real-time Transport Protocol (RTP) supports a range of video conferencing, telephony, and streaming video ap- plications, but offers few native security features. We discuss the problem of securing RTP, considering the range of applications. We outline why this makes RTP a difficult protocol to secure, and describe the approach we have recently proposed in the IETF to provide security for RTP applications. This approach treats RTP as a framework with a set of extensible security building blocks, and prescribes mandatory-to-implement security at the level of different application classes, rather than at the level of the media transport protocol
Yodel: A Layer 3.5 Name-Based Multicast Network Architecture For The Future Internet
Multicasting refers to the ability of transmitting data to multiple
recipients without data sources needing to provide more than one copy of the
data to the network. The network takes responsibility to route and deliver a
copy of each data to every intended recipient. Multicasting has the potential
to improve the network efficiency and performance (e.g., throughput and
latency) through transferring fewer bits in communicating the same data to
multiple recipients compared with unicast transmissions, reduce the amount of
networking resources needed for communication, lower the network energy
footprint, and alleviate the occurrence of congestion in the network. Over the
past few decades, providing multicast services has been a real challenge for
ISPs, especially to support home users and multi-domain network applications,
leading to the emergence of complex application-level solutions. These
solutions like Content Delivery and Peer-to-Peer networks take advantage of
complex caching, routing, transport, and topology management systems which put
heavy strains on the underlying Internet infrastructures to offer multicasting
services. In reality, the main motivation behind the design of these systems is
rather sharing content than offering efficient multicast services. In this
paper, we propound Yodel, a name-based multicast network architecture that can
provide multi-domain multicast services for current and future Internet
applications. Compared to the wider array of other name-based network
architectures with clean-slate infrastructure requirements, Yodel is designed
to provide multicast services over the current Internet infrastructure. Hence,
Yodel puts forward several design goals that distinguish it from other
name-based network architectures with inherent multicast capabilities. This
paper is prepared to discuss the Yodel architecture, its design goals, and
architectural functions.Comment: Contains animated figure
A Cross-System Approach for Multimedia Services with IP Multicast in 4G Networks
The increased demand for multimedia services by mobile end users in recent years have driven both Broadcast and Wireless Network operators to develop new systems and architectures for the deployment of such services. The proposed solutions are nonetheless limited either in terms of QoS or Capabilities to deliver new interactive services. This paper highlights strengths and drawbacks of the existing technologies in terms of QoS, Security and Mobility. In order to fill the gap between current solutions we propose a new architecture that builds itself on the synergies created by a heterogeneous network made of existing delivering technologies, such as 3GPP/MBMS and DVB, where services can be delivered to end-users in the most appropriate way for end-users and operators alike. A prototype implementation is further described.EU project - IST-2002- 506997 Daidalos I
An approach to enhance aggregated source specific multicast scheme
The Aggregated Source Specific Multicast (ASSM) scheme is proposed to overcome the limitations of Source Specific Multicast (SSM). It aims to handle the scalability issue of SSM. The key idea is that multiple groups are forced to share a single delivery tree. However, the ASSM scheme suffers from routers under utilization problem. In our previous work we have proposed an approach to overcome this problem. In this paper our proposed approach was presented and evaluated. It was shown that our proposed scheme results in achieving higher routers utilization
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