4,843 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
Scalability Improvement Of Multicast Source Movement Over Mobile Ipv6 Using Clustering Technique
Mobile IPv6 (MIPv6) describes how a mobile node can change its point of attachment to the Internet. While MIPv6 focuses on unicast communications, it also proposes two basic mechanisms, known as bi-directional tunnelling and remote subscription, to handle multicast communications with mobile members. In the mean time, the deployment of Source-Specific Multicast (SSM) is of great interest, using the Protocol Independent Multicast-Sparse Mode (PIM-SM) and Multicast Listener Discovery (MLDv2) protocols. In the particular case of mobile IPv6 SSM sources, the mechanism proposed in MIPv6 to support multicast communications introduced a number of problems that need to be addressed. First, in most scenarios the MIPv6 solution leads to suboptimal routing by setting up a tunnel to forward packets between the home agent in its home network and the current location in the foreign network. The use of a third party when roaming which is the home agent leads to suboptimal routing. Second, it introduces a central point of failure (i.e. the Home Agent (HA)) that is not to be neglected. The proposed MIPv6 solution also induces a great traffic concentration around this central point. Third, the processing task of the central point increases with the number of mobile sources it serves, thus reducing the efficiency of multicast delivery. The objective of this thesis is to remove some of the obstacles encountered in the way of multicast deployment in the Internet, thereby making Mobile IPv6 better equipped to support mobile SSM sources.
Recent proposals to provide multicasting over mobile IP focuses mainly on recipient mobility but little attention has been given to the case of source mobility. This thesis attempts to address this problem. The basic essence of the problem is that while the effect of receiver movement on the multicast tree is local, the effect of source movement may be global and it may affect the complete multicast delivery tree. The initial design was motivated by the need to support one-to-many and many-to-many applications in a scalable fashion. Such applications cannot be serviced efficiently with unicast delivery.
As the overall problem statement of âScalability Improvement of Multicast Source Movement over IPv6 Using Clustering Techniqueâ is extremely complex, we divide the problem into the following components: build the multicast delivery tree for source specific multicast which is a routing issue; clustering receivers based on their IPv6 addresses; improve the state scalability of these clusters which is a deployment issue; find an efficient way for service distribution which is a deployment issue as well; and finally, the seamless integration of the work with Mobile IPv6 allowing it to support multicast efficiently for mobile nodes. The combined solution provides a comprehensive procedure for planning and managing a multicast-based IPv6 network.
The outcome of this thesis are: a software to represent an architecture of a multicast delivery tree for one-to-many type of group communication, a group management scheme that could handle the end nodes subscription/un-subscription process with the required updates, an average subscription delay of between 0.255 ms-0.530 ms and un-subscription delay of between 0.0456 ms-0.087 ms for up to 50000 nodes, an approach to multicast forwarding state reduction that could support small-size groups as well as large-size groups, and finally the integration of the work with Mobile IPv6 to handle the multicast source movement
Multicast broadcast services support in OFDMA-based WiMAX systems [Advances in mobile multimedia]
Multimedia stream service provided by broadband wireless networks has emerged as an important technology and has attracted much attention. An all-IP network architecture with reliable high-throughput air interface makes orthogonal frequency division multiplexing access (OFDMA)-based mobile worldwide interoperability for microwave access (mobile WiMAX) a viable technology for wireless multimedia services, such as voice over IP (VoIP), mobile TV, and so on. One of the main features in a WiMAX MAC layer is that it can provide'differentiated services among different traffic categories with individual QoS requirements. In this article, we first give an overview of the key aspects of WiMAX and describe multimedia broadcast multicast service (MBMS) architecture of the 3GPP. Then, we propose a multicast and broadcast service (MBS) architecture for WiMAX that is based on MBMS. Moreover, we enhance the MBS architecture for mobile WiMAX to overcome the shortcoming of limited video broadcast performance over the baseline MBS model. We also give examples to demonstrate that the proposed architecture can support better mobility and offer higher power efficiency
Efficient Micro-Mobility using Intra-domain Multicast-based Mechanisms (M&M)
One of the most important metrics in the design of IP mobility protocols is
the handover performance. The current Mobile IP (MIP) standard has been shown
to exhibit poor handover performance. Most other work attempts to modify MIP to
slightly improve its efficiency, while others propose complex techniques to
replace MIP. Rather than taking these approaches, we instead propose a new
architecture for providing efficient and smooth handover, while being able to
co-exist and inter-operate with other technologies. Specifically, we propose an
intra-domain multicast-based mobility architecture, where a visiting mobile is
assigned a multicast address to use while moving within a domain. Efficient
handover is achieved using standard multicast join/prune mechanisms. Two
approaches are proposed and contrasted. The first introduces the concept
proxy-based mobility, while the other uses algorithmic mapping to obtain the
multicast address of visiting mobiles. We show that the algorithmic mapping
approach has several advantages over the proxy approach, and provide mechanisms
to support it. Network simulation (using NS-2) is used to evaluate our scheme
and compare it to other routing-based micro-mobility schemes - CIP and HAWAII.
The proactive handover results show that both M&M and CIP shows low handoff
delay and packet reordering depth as compared to HAWAII. The reason for M&M's
comparable performance with CIP is that both use bi-cast in proactive handover.
The M&M, however, handles multiple border routers in a domain, where CIP fails.
We also provide a handover algorithm leveraging the proactive path setup
capability of M&M, which is expected to outperform CIP in case of reactive
handover.Comment: 12 pages, 11 figure
Random Linear Network Coding for 5G Mobile Video Delivery
An exponential increase in mobile video delivery will continue with the
demand for higher resolution, multi-view and large-scale multicast video
services. Novel fifth generation (5G) 3GPP New Radio (NR) standard will bring a
number of new opportunities for optimizing video delivery across both 5G core
and radio access networks. One of the promising approaches for video quality
adaptation, throughput enhancement and erasure protection is the use of
packet-level random linear network coding (RLNC). In this review paper, we
discuss the integration of RLNC into the 5G NR standard, building upon the
ideas and opportunities identified in 4G LTE. We explicitly identify and
discuss in detail novel 5G NR features that provide support for RLNC-based
video delivery in 5G, thus pointing out to the promising avenues for future
research.Comment: Invited paper for Special Issue "Network and Rateless Coding for
Video Streaming" - MDPI Informatio
A two-way interactive broadband satellite architecture to break the digital divide barrier
September 24-26, 2007, Turin, Ital
TV-Centric technologies to provide remote areas with two-way satellite broadband access
October 1-2, 2007, Rome, Italy TV-Centric Technologies To Provide Remote Areas With Two-Way Satellite Broadband Acces
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