PIM SM relies on an explicit joining request before attempting to send multicast data to receivers of a multicast group. The assumption in SM is that relatively few users need the multicast information and therefore PIM SM starts with no flooding of multicast. In short order, router-to-router PIM Join messages cause the multicast stream to be forwarded across links to where it is needed.
It is required only in networks running PIM SM and is needed only to start new sessions with sources and receivers. A Designated Router DR is the router on a subnet that is selected to control multicast routes for the members on its directly attached subnet.
This source tree does not include the RP unless the RP is located within the shortest path between the source and receiver. Auto-RP automates the distribution of group-to-RP mappings. To make auto-RP work, a router must be designated as an RP mapping agent that receives the RP announcement messages from the RPs and arbitrates conflicts.
Each method for configuring an RP has its strengths, weaknesses, and complexity.
Auto-RP is typically used in a conventional IP multicast network given that it is straightforward to configure, well tested, and stable. IGMPv1 defined the basic mechanism. Version 3 adds source awareness allowing the inclusion or exclusion of sources. IGMP allows group membership lists to be dynamically maintained.
MLDv2 is a protocol that allows a host to inform its neighboring routers of its desire to receive IPv6 multicast transmissions; it is similar to and based on IGMPv3 used in the IPv4 context. The protocol announces active sources to MSDP peers. MPBGP is a protocol that defines multiprotocol extensions to the BGP, the unicast interdomain protocol that supports multicast-specific routing information.
It carries multiple instances of routes for unicast routing as well as multicast routing.
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Pragmatic General Multicast PGM is a reliable multicast transport protocol for applications that require ordered, duplicate-free multicast data delivery. The protocol guarantees that a receiver in a multicast group receives all data packets from direct transmissions or via retransmissions of lost packets. PGM can detect unrecoverable data packet loss. Some of these protocols but not all are covered in the chapters. Figure 1. It should be noted that the design and turnup of IP multicast networks is fairly complex. Applications such as datacasting e. Applications such as video are very sensitive to end-to-end delay, jitter, and uncorrectable packet loss; QoS considerations are critical.eqyhacem.cf
IJCA - A Multicast IPTV Bandwidth Saving Method
These networks tend to have fewer hops, and pruning may be somewhat trivially implemented by making use of a simplified network topology. IPTV services enable advanced content viewing and navigation by consumers; the technology is rapidly emerging and becoming commercially available. Traditional phone carriers find themselves challenged in the voice arena by VoIP and other providers ; their Internet services are also challenged in the broadband Internet access arena by cable TV companies ; and their video services are nascent and challenged by a lack of deployed technology.
Multimedia and new media services are a way to improve telco revenues e. As far back as , 9. Table 1. Unfortunately, none of these plans led to actual TV services. The problem was that the emphasis by the telcos for local delivery was totally pivoted on Digital Subscriber Line DSL. DSL had a bandwidth range of around 1. Consequently, the use of MPEG-1 encoding techniques operating at 1. Now a decade later, in the mid-to-late s, the recognition has emerged that an IP infrastructure with IP multicast is the best mechanism for distribution of entertainment video by the telcos, aiming at a —channel pool and typically with up to three simultaneous streams of video traffic per domicile based on efficient, yet high-quality, MPEG-4 standards e.
Figures 1. GTE Florida Inc. GTE California Inc. GTE Hawaiian Tel. Homes Type of Proposal Content aggregation Content encoding [e. DSL can allow voice and high-speed data to be sent simultaneously over the same line. ADSL FullAccess technology that offers differing upload and download speeds Rate and can be configured to deliver up to 6 mbps kbps from the Asymmetric network to the customer. This type of DSL is the most predominant in commercial use for business and residential customers around the world. Good for general Internet access and for applications where downstream speed is most important, such as video on demand.
ITU-T recommendation G. ITU recommendation G. A standard that was specifically developed to meet the plug-and-play G. VDSL A standard for up to 26 Mbps over distances up to 50 m on short loops such as from fiber to the curb. In most cases, VDSL lines are served from neighborhood cabinets that link to a central office via optical fiber.
VDSL is currently being introduced in market trials to deliver video services over existing phone lines. VDSL can also be configured in symmetric mode. A vendor-proprietary version of symmetric DSL that may include bit rates to and from the customer ranging from kbps to 2. SDSL is an umbrella term for a number of supplier-specific implementations over a single copper pair providing variable rates of symmetric service.
SHDSL systems may operate at many bit rates, from kbps to 5.
For example, with two pairs of wire, 1. SHDSL is best suited to data-only applications that need high upstream bit rates. SHDSL is being deployed primarily for business customers. A DSL variety created in the late s that delivers symmetric service at speeds up to 2. Available at 1. Seen as an economical replacement for T1 or E1, it uses one, two, or three twisted copper pairs.
A variant of DSL that delivers 1. HDSL2 does not provide standard voice telephone service on the same wire pair. Has the ability to deliver services through a DLC Services Digital Digital Loop Carrier: a remote device often placed in newer neighborhoods Network DSL to simplify the distribution of cable and wiring from the phone company. While DLCs provide a means of simplifying the delivery of traditional voice services to newer neighborhoods, they also provide a unique challenge in delivering DSL into those same neighborhoods.
Pdf Ip Multicast With Applications To Iptv And Mobile Dvb H
Courtesy: DSL Forum. DVB system providers develop their proprietary conditional access systems within these specifications DVB transports include metadata called Service Information DVB-SI that links the various elementary streams into coherent programs and provides human-readable descriptions for electronic program guides This topic will be reexamined in Chapter Next, we briefly discuss DVB-H applications. It addresses the requirements for reliable, high-speed, high-data-rate reception for a number of mobile applications, including real-time video to handheld devices.
DVB-H is generating significant interest in the broadcast and telecommunications worlds, and DVB-H services are expected to start at this time. Industry proponents expect to see million DVB-H-capable handsets to be deployed by Digital Video Broadcasting DVB is a consortium of over companies in the fields of broadcasting and manufacturing that work cooperatively to establish common international standards for digital broadcasting.
When DVB-T was first published in , it was not designed to target mobile receivers. However, DVB-T mobile services have been launched in a number of countries. Indeed, with the advent of diversity antenna receivers, services that target fixed reception can now largely be received on the move as well. DVB-T is deployed in more than 50 countries. Yet, a new standard was sought, namely DVB-H. Despite the success of mobile DVB-T reception, the major concern with any handheld device is that of battery life.
The current and projected power consumption of DVB-T front ends is too high to support handheld receivers that are expected to last from one to several days on a single charge. These requirements were drawn up after much debate and with an eye on emerging convergence devices providing video services and other broadcast data services to second- and not quite third-generation 2. Furthermore, all this should be possible while maintaining maximum compatibility with existing DVB-T networks and systems.
In order to meet these requirements, the newly developed DVB-H specification includes the capabilities discussed next. Time Slicing. In addition, with the aid of enhanced in-depth interleavers in the 2K and 4K modes, DVB-H has even better immunity to ignition interference.
The addition of an optional, multiplexer-level, forward error correction scheme means that DVB-H IP Multicast Content acquisition Content aggregation Content encoding low bit rate Provisioning of service Operation of network Provisioning of cellular Operation of cellular network Transmitter Buy content rights Figure 1. A 21 transmissions can be even more robust. This is advantageous when considering the hostile environments and poor but fashionable antenna designs typical of handheld receivers.
However, a 5-MHz option is also specified for use in nonbroadcast environments. Broadcasting is an efficient way of reaching many users with a single configurable service. DVB-H combines broadcasting with a set of measures to ensure that the target receivers can operate from a battery and on the move and is thus an ideal companion to 3G telecommunications, offering symmetric and asymmetric bidirectional multimedia services.
Such trials help frequency planning and improve understanding of the complex issue of interoperability with telecommunications networks and services. This topic will be reexamined in Chapter Chapter 4 covers the important topic of dynamic host registration using the IGMP.
Chapter 9 covers IP multicasting in IPv6 environments. Chapter 10 looks at MLD snooping switches. Deering, July Waitzman, C. Partridge, S.
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Deering, November Pusateri, June status: historic. Moy, March Farinacci, A. Helmy, et al. Ballardie, September Fenner, November status: standard. Farinacci, D. Meyer, Y.