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4f7834675cbb2bc6f0267bc4888c3a84 | 102 311 | 4.3.3.4 Working with antenna spacing below the sub-optimal condition | Figure 4.3.3.4.a illustrates the singular values/SDGs of the two spatial channels in 23 GHz of 5 km hop distance for a 2 × 2 MIMO system. From figure 4.3.3.4.a it can be viewed that moving from optimal antenna spacing may cause only degradation in performance. As an example it can be seen from the diagram that 5,7 m is... |
4f7834675cbb2bc6f0267bc4888c3a84 | 102 311 | 4.3.3.5 Channel matrix considering link propagation | In real link also propagation effects need to be considered. This is important in order to determinate the MIMO link performance, as it will be seen in term of Capacity in clause 4.4. +3 dB (SDG) ETSI ETSI TR 102 311 V1.2.1 (2015-11) 22 In practise even the path loss attenuation and any fading attenuation effects need ... |
4f7834675cbb2bc6f0267bc4888c3a84 | 102 311 | 4.3.3.6 Multi-polarized MIMO | In a MIMO system also the two different polarizations, horizontal and vertical ones, may be used in order to create diversity. Furthermore, Multi-polarized MIMO can help to increase the number of sub-channels without increasing the total number of antenna by using dual polarized antenna. This is also important to save ... |
4f7834675cbb2bc6f0267bc4888c3a84 | 102 311 | 4.4 MIMO Performance | In order to show MIMO Capacity improvement it is necessary to recall SISO Capacity limit. It is the famous Shannon- Hartley Theorem which states that the Capacity is: ( ) [ ] bit/s/Hz 1 log2 ρ + = SISO C Where: B N S ⋅ = 0 ρ = SNR S̅ = Averaged received Power [W] N0 = Noise Power Spectral Density [W/Hz] B = Bandwidth [... |
4f7834675cbb2bc6f0267bc4888c3a84 | 102 311 | 4.5 The spatial frequency reuse canceller | |
4f7834675cbb2bc6f0267bc4888c3a84 | 102 311 | 4.5.1 Open-Loop MIMO | When the channel is unknown as in open-loop MIMO, the spatial frequency reuse canceller try to suppress the mutual- interference that comes from the "M" TX sub-channels from the useful sub-channel at each of the "N" receiver. These kinds of techniques are similar to ones used by "traditional" interference suppression i... |
4f7834675cbb2bc6f0267bc4888c3a84 | 102 311 | 4.5.2 Closed-Loop MIMO | In closed-loop MIMO some information related to the estimated channel is fed back from the RX to the TX. In order to reduce the information volume a quantized version of the channel state information is provided to the transmitter (figure 4.5.2.a). Many different algorithms for closed-loop MIMO were presented which req... |
4f7834675cbb2bc6f0267bc4888c3a84 | 102 311 | 4.5.3 MIMO receiver cancellation technique comparison | Following figure 4.5.3 shows Capacity Gain versus Inter-antenna Distance slope when different receiver cancellation techniques are used: 1) Blue curve: all the four MIMO sub-channels have the same spectrum efficiency and the transmission power is allocated uniformly between the sub-channels. The receiver algorithm is t... |
4f7834675cbb2bc6f0267bc4888c3a84 | 102 311 | 5 Verification by field trial and simulation | |
4f7834675cbb2bc6f0267bc4888c3a84 | 102 311 | 5.1 Overview | In order to verify the above described theoretical claims two field tests are presented: • A 5 GHz field trial. It was implemented by using generic test equipment at 5,8 GHz in urban environment scenario. • An 18 GHz field trial. It was performed by using its own 18 GHz MW equipment with a new MIMO Modem board in LOS p... |
4f7834675cbb2bc6f0267bc4888c3a84 | 102 311 | 5.2 5 GHz field trial | |
4f7834675cbb2bc6f0267bc4888c3a84 | 102 311 | 5.2.1 MIMO channel measurement experiment - Aims | Measurement of the steady state after settling of multipath transient, in single frequency of 5,8 GHz the complex (amplitude and phase) channel transfer function matrix (four inputs, four outputs) of a spatial 4 × 4 MIMO channel. It was decided to select low frequency in order to evaluate the scattered channel model an... |
4f7834675cbb2bc6f0267bc4888c3a84 | 102 311 | 5.2.2 MIMO channel measurement experiment - Configuration and plan | Antenna configurations: • Linear array - four evenly spaced antennas - vertical and horizontal polarizations; • Element spacing - close (30 cm) to wide (greater than 3 m). In order to perform the test a special test setup was built. The test was conducted in four different terrains. As an accessory to the trial a speci... |
4f7834675cbb2bc6f0267bc4888c3a84 | 102 311 | 5.2.3 MIMO channel measurement setup | |
4f7834675cbb2bc6f0267bc4888c3a84 | 102 311 | 5.2.3.1 Tx setup | Figure 5.2.3.1 describes the TX setup which comprises: sweeper synthesized source, power amplifier RF switch and four horn antennas. A special switch controller commutate between the four antenna such that only one antenna transmitted in a certain instant. Furthermore one of the switch state is "mute - no transmitting"... |
4f7834675cbb2bc6f0267bc4888c3a84 | 102 311 | 5.2.3.2 RX setup | Figure 5.2.3.2 describes the RX setup which comprises: two network analysers that act as four channel complex (amplitude and phase) receivers, synthesizer as local oscillator and quad-channel RF front-end. All four receiver inputs operate in parallel. ETSI ETSI TR 102 311 V1.2.1 (2015-11) 30 N E T W O R K A N A L Y S E... |
4f7834675cbb2bc6f0267bc4888c3a84 | 102 311 | 5.2.3.3 Test results and analysis | |
4f7834675cbb2bc6f0267bc4888c3a84 | 102 311 | 5.2.3.3.1 Results | In order to verify the spatial frequency reuse performance the main figures of merit were the four normalized singular values of the channel. The test was conducted between two windows of two different building with 700 m distance. Table 5.1.3.3.1 holds the singular values results of the different tests. Every test was... |
4f7834675cbb2bc6f0267bc4888c3a84 | 102 311 | 5.2.3.3.2 Analysis | From the values in table 5.2.3.3.1.a it can be concluded that the singular values dependence on the antenna spacing can be evaluated and drawn in figure 5.2.3.3.2.a, which depicts the theoretical dependence comparable to the trial resulted dependence. The channel impulse response, reported in the four charts of figure ... |
4f7834675cbb2bc6f0267bc4888c3a84 | 102 311 | 5.2.3.3.3 MIMO channel measurement experiment - Conclusions | • Geometric separation of antennas always works according to theory. - Line-of-Sight yields low propagation loss. - Line-of-Sight yields "static" channel parameters. • Difficult to find reflections with energies comparable to Line-of-Sight condition. - Moderate singular value spread even with some reflections. - Low si... |
4f7834675cbb2bc6f0267bc4888c3a84 | 102 311 | 5.3 18 GHz field trial | |
4f7834675cbb2bc6f0267bc4888c3a84 | 102 311 | 5.3.1 MIMO channel measurement experiment - Aims | A MIMO trial was set and tested in order to analyze Multi-Polarized 2 × 2 MIMO in LOS channel without any power constraint (the MIMO transmission power is double with respect to the SISO one). The selected carrier frequency is 18 GHz with CS = 55 MHz and the modulation format is 256-QAM. The frequency band was chosen d... |
4f7834675cbb2bc6f0267bc4888c3a84 | 102 311 | 5.3.2 MIMO channel measurement experiment - Configuration and plan | The optimal antenna distance (dopt), over a 6,2 km link hop length, is 7,1 m but for practical installation matter it was only possible to install antennas with 4,3 m of separation. The last value corresponds to the 60 % of the optimal distance and it drives to around 4,5 dB drop in SNR gain. The MIMO configuration is ... |
4f7834675cbb2bc6f0267bc4888c3a84 | 102 311 | 5.3.3 MIMO channel measurement setup | In figure 5.3.3 a sketch of the used MIMO setup is presented. It comprises eight commercial ODUs and two IDUs with a new MIMO modem board, four dual-polarized 60 cm diameter dish antennas, a traffic generator/analyzer instrument, a data logger, a weather station meter and laptop for controlling the link. Site B Site A ... |
4f7834675cbb2bc6f0267bc4888c3a84 | 102 311 | 5.3.4 Test results and analysis | In the three layers of figure 5.3.4 are shown: • The RSL values for the four MIMO sub-channel in one direction. Due to many tolerance sources in the link setup the RSL values are not at the same level, anyway the RSL values for links with the same polarization are kept in a reasonable ± 3 dB spread. • The MSE (SNR) val... |
4f7834675cbb2bc6f0267bc4888c3a84 | 102 311 | 6 Verification by simulation | |
4f7834675cbb2bc6f0267bc4888c3a84 | 102 311 | 6.1 The simulation block diagram | As an additional engine to the trial verification at 5 GHz, in order to verify the spatial frequency reuse theory, to learn about sensitivities and to evaluate the performance a special simulation was developed. Another goal of the simulation was to develop algorithms of SFRC and to assist with the implementation phase... |
4f7834675cbb2bc6f0267bc4888c3a84 | 102 311 | 6.2 The simulation results | Table 6.2 summarizes the results for few variations of multipath scattering and spatial phase noise of TX and RX performances by measuring C/N ratio at the detector. Table 6.2: Resulted singular values in geometrical spatial frequency reuse Digital Modulation: 128 QAM Analog Modulation: Fs/4, SAW filter Self Noise leve... |
4f7834675cbb2bc6f0267bc4888c3a84 | 102 311 | 7 Void | Void. ETSI ETSI TR 102 311 V1.2.1 (2015-11) 38 |
4f7834675cbb2bc6f0267bc4888c3a84 | 102 311 | 8 Practical implementation | |
4f7834675cbb2bc6f0267bc4888c3a84 | 102 311 | 8.1 Overview | Similar to the implementation of the XPIC, the SFRC can be implemented with split-mount architecture with separate ODUs which are tied together with the IDU (see figure 5.3.3). ODUs should be synchronized together in the symbol timing and the reference source to the local oscillators that form the carrier frequency. At... |
4f7834675cbb2bc6f0267bc4888c3a84 | 102 311 | 8.2 Installation Issues | Out of the antenna spacing and orientation, there is no any special requirements for the installation of MIMO system. The installation is very much similar to a conventional PP link; each antenna direction can be adjusted separately according to line of the antenna array. In figure 8.2.a and figure 8.2.b the simulation... |
4f7834675cbb2bc6f0267bc4888c3a84 | 102 311 | 8.3 Availability Calculation | The MIMO link availability can be expressed by the following formula: { } det log 1 ) ( 1 2 ⎪⎭ ⎪⎬ ⎫ ⎪⎩ ⎪⎨ ⎧ < ⎥⎦ ⎤ ⎢⎣ ⎡ ⎟⎠ ⎞ ⎜⎝ ⎛ × + − = < − = R H H M P I P R H C P ty Availabili H f f N f MIMO Where "R" is the MIMO data rate [bit/s/Hz] at which the link is designed to work. The information about the radio channel sta... |
4f7834675cbb2bc6f0267bc4888c3a84 | 102 311 | 9 Summary | Spatial multiplexing is another additional frequency reuse method to the current CCDP one that is suitable for point-to- point application. The present document describes the implementation of the spatial multiplexing in microwave PP equipment which exploits the geometry of the link (i.e. antennas separation) by using ... |
4892bb11effcc41a47b07ac2eca62d3b | 102 070-1 | 1 Scope | The present document provides guidance in assessing the technical difficulties with the application of harmonized EMC standards to combined products, which include a radio and/or a telecommunication function. Examples to be covered include products containing multiple radio technologies, radio in IT equipment, radio in... |
4892bb11effcc41a47b07ac2eca62d3b | 102 070-1 | 2 References | For the purposes of this Technical Report (TR) the following references apply: [1] Directive 1999/5/EC of the European Parliament and of the Council of 9 March 1999 on radio equipment and telecommunications terminal equipment and the mutual recognition of their conformity (R&TTE Directive). [2] Council Directive 89/336... |
4892bb11effcc41a47b07ac2eca62d3b | 102 070-1 | 3 Definitions and abbreviations | |
4892bb11effcc41a47b07ac2eca62d3b | 102 070-1 | 3.1 Definitions | For the purposes of the present document, the following terms and definitions apply: combined equipment: any equipment made of two or more individual products or functions NOTE: At least one of the individual products or functions falls within the scope of the R&TTE Directive [1]. The result of this combination provide... |
4892bb11effcc41a47b07ac2eca62d3b | 102 070-1 | 3.2 Abbreviations | For the purposes of the present document, the following abbreviations apply: AC Alternating Current DC Direct Current EMC ElectroMagnetic Compatibility EU European Union GPRS General Packet Radio Service GSM Global System for Mobile communications ISM Industrial, Scientific and Medical equipment ITE Information Technol... |
4892bb11effcc41a47b07ac2eca62d3b | 102 070-1 | 4 Products considered in the present document | 4.1 Relationship between individual components of a combined product In all of the various scenarios at least one of the products or functions falls within the scope of the R&TTE Directive [1]. Figures 3 to 9 illustrate the various product combinations considered in the present document. ETSI ETSI TR 102 070-1 V1.2.1 (... |
4892bb11effcc41a47b07ac2eca62d3b | 102 070-1 | 4.1.1 Scenario 1 | Product A Product B Product A Product C Product B Product A Product B Product A is placed on the market in accordance with the relevant EU directive(s). Product B is placed on the market in accordance with the relevant EU directive(s). Product C is a new product constructed by combining Product A and B into a single en... |
4892bb11effcc41a47b07ac2eca62d3b | 102 070-1 | 4.1.2 Scenario 2 | Product A Product B Figure 4 Product A is a product in its own right and is placed upon the EU market in accordance with the relevant directives. Product B is dependent upon product A and relies upon product A for control and possibly power. Product B is physically installed within product A according to the manufactur... |
4892bb11effcc41a47b07ac2eca62d3b | 102 070-1 | 4.1.3 Scenario 3 | Product A Product B Figure 5 Product A is a product in its own right and is placed upon the EU market in accordance with the relevant directives. Product B is dependent upon product A and relies upon product A for control and possibly its power supply. Product B is physically connected by either cable or fibre to produ... |
4892bb11effcc41a47b07ac2eca62d3b | 102 070-1 | 4.1.4 Scenario 4 | Product A Product B1 Product B2 Figure 6 This scenario is a combination of the previous two scenarios. Product B1 is physically installed within product A according to the manufacturers instruction, e.g. plug and socket, hard wiring, while product B2 is physically connected by either cable or fibre to product A and may... |
4892bb11effcc41a47b07ac2eca62d3b | 102 070-1 | 4.1.5 Scenario 5 | Product A Function B Figure 7 Product A was a product in its own right and was placed upon the EU market in accordance with the relevant directives. In this scenario an additional function, function B, is incorporated into product A during a design evolution and cannot be identified as a separate part of product A. How... |
4892bb11effcc41a47b07ac2eca62d3b | 102 070-1 | 4.1.6 Scenario 6 | Product A Function B Figure 8 Function B is part of product A which was added during design. Product A cannot be operated without using function B. ETSI ETSI TR 102 070-1 V1.2.1 (2003-12) 13 |
4892bb11effcc41a47b07ac2eca62d3b | 102 070-1 | 4.1.7 Scenario 7 | Product A Product B Figure 9 Products A and B are products in their own right. However, product A relies upon product B for its operation. Product B may work with other products. The link between product A and B may be either a physical link (e.g. cable) or non-physical (e.g. radio). 5 Application of harmonized standar... |
4892bb11effcc41a47b07ac2eca62d3b | 102 070-1 | 5.1 Functional dependencies | The following table takes the above scenarios, from clause 4.1, and places them into a category dependant upon whether the individual products/functions can operate independently of each other. The final column in the table indicates where guidance upon application of harmonized standards can be found. Multi radio prod... |
4892bb11effcc41a47b07ac2eca62d3b | 102 070-1 | 5.2.1 Emissions | It is recognized that the individual products which make up the combined equipment may have been assessed to different harmonized EMC standards with differing emission limits. However, for combined equipment, the limits used to demonstrate compliance should be taken from the harmonized EMC standard for the primary prod... |
4892bb11effcc41a47b07ac2eca62d3b | 102 070-1 | 5.2.2 Immunity | It is recognized that the individual products which make up the combined equipment may have been assessed to different harmonized EMC standards with differing immunity test levels, phenomena and performance criteria. However, for combined equipment, the harmonized EMC standard for the primary product (declared by the m... |
4892bb11effcc41a47b07ac2eca62d3b | 102 070-1 | 5.3.1 Products physically incorporated within another product | When a combined equipment is made up from the incorporation of one or more products into another product, then the assessment of the combined equipment should be on the same basis as that recommended in clauses 5.2.1 and 5.2.2. 5.3.2 Products connected to, but not physically incorporated within, another product When a ... |
4892bb11effcc41a47b07ac2eca62d3b | 102 070-1 | 5.4.1 Emissions | The limits and tests used to demonstrate compliance of the combined equipment should be taken from the harmonized EMC standard relevant to the primary function (declared by the manufacturer). Ports not covered in the harmonized EMC standard relevant to the primary function should be assessed against the details set out... |
4892bb11effcc41a47b07ac2eca62d3b | 102 070-1 | 5.4.2 Immunity | The test levels, performance criteria and test methods used to demonstrate compliance of the combined equipment should be taken from the harmonized EMC standard for the primary function (declared by the manufacturer). The following additional immunity tests should be applied to combined equipment if not already include... |
4892bb11effcc41a47b07ac2eca62d3b | 102 070-1 | 6.1 Multi-radio equipment capable of independent transmission | If the individual radio products and their corresponding radio links operate independently in normal usage (as declared by the manufacturer), then separate testing should be used. In this case the individual radio products should be assessed to the appropriate harmonized EMC product standards. ETSI ETSI TR 102 070-1 V1... |
8f4fe51f2c92e0bc31f3d83583a5f46f | 102 156 | 1 Scope | The focus of the present document is satellite-based multicasting, including IP multicasting. The scope of the present document is to: • identify relevant multicast issues, use cases service architectures for satellite multicasting; • identify satellite specific issues and technical requirements for satellite multicast... |
8f4fe51f2c92e0bc31f3d83583a5f46f | 102 156 | 2 References | For the purposes of this Technical Report (TR) the following references apply. Referenced documents which are not found to be publicly available in the expected location might be found at http://docbox.etsi.org/Reference. [1] ETSI TR 101 374-1: "Satellite Earth Stations and Systems (SES); Broadband satellite multimedia... |
8f4fe51f2c92e0bc31f3d83583a5f46f | 102 156 | 3 Definitions and abbreviations | |
8f4fe51f2c92e0bc31f3d83583a5f46f | 102 156 | 3.1 Definitions | For the purposes of the present document, the following terms and definitions apply: gateway: network point that acts as an entrance to another network; often a connection point between a satellite network and the core network NOTE: Traffic exits to the core network via a gateway when it originates in the satellite net... |
8f4fe51f2c92e0bc31f3d83583a5f46f | 102 156 | 3.2 Abbreviations | For the purposes of the present document, the following abbreviations apply: AAL ATM Adaptation Layer ACK ACKnowledgement AFDP Adaptive File Distribution Protocol API Application Programming Interface ARP Address Resolution Protocol ARQ Automatic Repeat reQuest AS Autonomous System ASM Any Source Multicast AVT Audio/Vi... |
8f4fe51f2c92e0bc31f3d83583a5f46f | 102 156 | 4 Multicasting background | The purpose of this clause is to present relevant, but non-satellite specific, multicast standards, procedures and terminology. Readers familiar with these concepts may skip the clause. ETSI ETSI TR 102 156 V1.1.1 (2003-04) 13 |
8f4fe51f2c92e0bc31f3d83583a5f46f | 102 156 | 4.1 Introduction | Multicasting implies that addressed data is transmitted to several recipients with a single communications process. Multicast has a single stream of data for many users, in contrast to unicast technology, which employs a separate stream for each user, and broadcast, where all receivers receive the same non-addressed co... |
8f4fe51f2c92e0bc31f3d83583a5f46f | 102 156 | 4.2 IP multicasting | Multicast is communication between (usually) a single sender and multiple receivers on a network. Internet Protocol (IP) multicast is a bandwidth-conserving technology that reduces traffic by simultaneously delivering a single stream of information to thousands of corporate recipients and homes. Applications that take ... |
8f4fe51f2c92e0bc31f3d83583a5f46f | 102 156 | 4.3 IP broadcasting | Broadcast may be considered a special case of multicast, and in fact in IPv6 it only exists as a part of multicast. So, broadcast is a multicast group whose members include all members in a subnetwork. Subnetworks can be point-to-point or shared. A point-to-point subnet has exactly two endpoint components (hosts or gat... |
8f4fe51f2c92e0bc31f3d83583a5f46f | 102 156 | 4.4 IP multicast addresses | In IETF RFC 3170, we find mentioned that one of the first questions facing a multicast application developer is what multicast address to use. Multicast addresses are not assigned to individual hosts, assignments can change dynamically, and addresses sometimes have semantics of their own (e.g. Admin Scoping). Multicast... |
8f4fe51f2c92e0bc31f3d83583a5f46f | 102 156 | 4.4.1 Class D addresses | Multicast addresses specify an arbitrary group of IP hosts that have joined the group and wish to receive traffic sent to this group. The Internet Assigned Numbers Authority (IANA) controls the assignment of IP multicast addresses. IANA has assigned the Class D address space to be used for IP multicast. This means that... |
8f4fe51f2c92e0bc31f3d83583a5f46f | 102 156 | 4.4.2 MAC layer mapping | To support IP multicasting, the Internet authorities have reserved the multicast address range of 01-00-5E-00-00-00 to 01-00-5E-7F-FF-FF for Ethernet and Fiber Distributed Data Interface (FDDI) media access control (MAC) addresses. The high order 25 bits of the 48-bit MAC address are fixed and the low order 23 bits are... |
8f4fe51f2c92e0bc31f3d83583a5f46f | 102 156 | 4.5 IP Multicast Routing Protocols | For multicast, the optimal solution (minimum cost to interconnect N nodes) would impose a (NP-hard) Steiner tree computation. Unfortunately, no multicast routing protocol today is able to maintain such an optimal tree. Different multicast protocols will therefore, in general, generate different trees. Info: Steiner tre... |
8f4fe51f2c92e0bc31f3d83583a5f46f | 102 156 | 4.5.1 Distance Vector Multicast Routing Protocol (DVMRP) | DVMRP (IETF RFC 1075 [23]) is an interior gateway protocol; suitable for use within an autonomous system, but not between different autonomous systems. DVMRP is not for use in routing non-multicast datagrams, so a router that routes both multicast and unicast datagrams must run two separate routing processes. DVMRP is ... |
8f4fe51f2c92e0bc31f3d83583a5f46f | 102 156 | 4.5.2 Protocol Independent Multicast (PIM) | PIM is a router-to-router protocol that supports multicast traffic over existing unicast routing protocols. PIM was designed to avoid the scaling problems and the potential performance problems. PIM operates in either sparse or dense mode. There is now (Q1/2003) an Internet draft that defines a portion of the Managemen... |
8f4fe51f2c92e0bc31f3d83583a5f46f | 102 156 | 4.5.2.1 Dense Mode | Dense Mode (DM) is intended for networks in which most LANs need to receive the multicast (such as LAN TV and corporate and financial information broadcasts). DM uses reverse-path forwarding, where the traffic is initially sent to all routers, and those that do not need a traffic feed will reply with a prune message th... |
8f4fe51f2c92e0bc31f3d83583a5f46f | 102 156 | 4.5.2.2 Sparse Mode | In contrast to Dense Mode, Sparse Mode protocols (e.g. PIM-SM and CBT) do not employ a "Flood and Prune" mode of operation and are much better suited to links with appreciable round trip delay. These protocols are also preferred in an Internet context, and are considered better suited for satellite multicast applicatio... |
8f4fe51f2c92e0bc31f3d83583a5f46f | 102 156 | 4.5.2.2.1 Rendezvous Point (RP) | PIM-SM requires at least one Rendezvous Point, or RP, per domain to function. Initially, receivers do not need to know the location of a source to function, as the address of the RP is distributed throughout the PIM-domain. When a receiver wants to join a group, G, it sends an IGMP member report to its first hop router... |
8f4fe51f2c92e0bc31f3d83583a5f46f | 102 156 | 4.6 Inter-domain multicast | |
8f4fe51f2c92e0bc31f3d83583a5f46f | 102 156 | 4.6.1 General | While intra-domain multicast routing is fairly well established, with Protocol Independent Multicast-Sparse Mode (PIM-SM) accepted as the de facto multicast routing protocol, inter-domain multicast routing presents another set of challenges. The focus is on how services can be shared and distributed between providers. ... |
8f4fe51f2c92e0bc31f3d83583a5f46f | 102 156 | 4.6.2 Multicast Source Discovery Protocol (MSDP) | MSDP is found in draft-ietf-msdp-spec-14.txt as of March 2003 [35], and the below text is taken form there. The Multicast Source Discovery Protocol, MSDP, describes a mechanism to connect multiple PIM-SM domains together. Each PIM-SM domain uses its own independent RP(s) and does not have to depend on RPs in other doma... |
8f4fe51f2c92e0bc31f3d83583a5f46f | 102 156 | 4.7 Internet Group Management | |
8f4fe51f2c92e0bc31f3d83583a5f46f | 102 156 | 4.7.1 IGMP | The Internet Group Management Protocol (IGMP) is used to provide information about membership of multicast groups on a network. Hosts that wish to join a multicast group instruct their network adapter cards to listen for network frames specifying a special MAC address that corresponds to the multicast class D IPv4 addr... |
8f4fe51f2c92e0bc31f3d83583a5f46f | 102 156 | 4.7.2 PIM-SM/IGMPv3 interaction | A PIM-SM/IGMPv3 interaction takes place when a PM-SM router receives an IGMP message regarding a group address that is in the Any Source Multicast (ASM) range. This range is defined as the entire Class D multicast space excluding the global SSM range and any locally defined Source Specific space. PIM-SM join messages a... |
8f4fe51f2c92e0bc31f3d83583a5f46f | 102 156 | 4.8 Source Specific Multicast | Source Specific Multicasting (SSM) involves using the capabilities of IGMP v3 to tune PIM-SM to the needs of large scale, one-to-many, multi-casting, such as in web casting. IGMP v3 allows a source to explicitly request traffic from a particular (S,G) pair without using a Rendezvous Point at all. Edge routers must be s... |
8f4fe51f2c92e0bc31f3d83583a5f46f | 102 156 | 4.9 Time To Live (TTL) for multicast packets | The IP multicast routing protocol uses the Time to Live (TTL) field of IP datagrams to decide how far from a sending host a given multicast packet should be forwarded. The default TTL for multicast datagrams is 1, which will result in multicast packets going only to other hosts on the local network. A setsockopt(2) cal... |
8f4fe51f2c92e0bc31f3d83583a5f46f | 102 156 | 4.10 Multicast scoping | Not all groups need or should have a global scope. Scoping can be used to limit the region in which data is forwarded, which is useful for performance reasons with flood and prune multicast routing protocols. It also useful for application security reasons or because multicast addresses are a scarce resource. Scoping a... |
8f4fe51f2c92e0bc31f3d83583a5f46f | 102 156 | 4.10.1 TTL scoping | When an IP packet is sent, the IP header field Time to Live (TTL) is set to a value between zero and 255. Every time a router forwards the packet, it decrements the TTL field in the packet header, and if the value reaches zero, the packet is dropped. (TTL should in principle also be decremented if a packet is queued fo... |
8f4fe51f2c92e0bc31f3d83583a5f46f | 102 156 | 4.10.2 Administrative scoping | Administrative scoping is much more flexible than TTL scoping, but suffers from a number of disadvantages. In particular, it is not possible to tell from the address of a packet where it will go unless all the scope zones that the sender is within are known. Also, as administrative boundaries are bi-directional, one sc... |
8f4fe51f2c92e0bc31f3d83583a5f46f | 102 156 | 4.11 Reliable multicast protocols and architectures | The following classifications are based on [21] (M.Koyabe and G. Fairhurst. "Reliable Multicast Via Satellite: A Comparison Survey and Taxonomy", International Journal for Satellite Communications (IJSC), Vol:24(1), 21-26, 2001). |
8f4fe51f2c92e0bc31f3d83583a5f46f | 102 156 | 4.11.1 One-to-many (star-based) | One-to-many (Star-based) reliable multicast protocols, Reliable Multicast Transport Protocols are suited for data delivery from a single sender to multiple receivers, with minimal dependency on network elements. Most protocols use a receiver- or sender- initiation approach to achieve reliability. In a number of star-ba... |
8f4fe51f2c92e0bc31f3d83583a5f46f | 102 156 | 4.11.2 One-to-many (tree-based) | One-to-many (tree-based) protocols are reliable multicast protocols, which aggregate receivers into a tree-based structure. A set of multicast groups are used to establish a hierarchy of logical areas (one address per area) and retransmission responsibility is distributed over the acknowledgement tree (ACK tree) struct... |
8f4fe51f2c92e0bc31f3d83583a5f46f | 102 156 | 4.11.3 One-to-many (ring-based) | Ring-based protocols, Reliable Multicast Protocol (RMP) organize nodes into a ring. Each receiver in a ring maintains global session membership information. A token is based among all receivers to synchronies data transmissions and feedback of acknowledgements. It may also be used to synchronies the order of transmissi... |
8f4fe51f2c92e0bc31f3d83583a5f46f | 102 156 | 4.11.4 Many-to-many | The following are many-to-many protocol designs: • Scalable Reliable Multicast (SRM); • Pragmatic General Multicast (PGM); • Transport Protocol for Reliable Multicast (TRM); • Reliable Concurrent Multicast from Bursty Sources (RCMBS). Most many-to-many protocol designs are based on the SRM protocol. Both SRM and TRM su... |
8f4fe51f2c92e0bc31f3d83583a5f46f | 102 156 | 4.12 Multicast security | If the multicast transmission is of a sensitive nature, it should be encrypted. This means that the all members of the group must share the same encryption key to take benefit of the multicast transmission. There are many factors that must be taken into account when developing the desired key management architecture. I... |
8f4fe51f2c92e0bc31f3d83583a5f46f | 102 156 | 4.13 IPv6 and IPv4 multicast issues | Multicast applications have been developed for both IPv4 and IPv6. However IPv6 extends the IP multicasting capabilities by defining a much larger multicast address space. All of the IPv6 hosts and routers are required to support multicast. IPv6 also has no broadcast address as such; it obtains various multicast addres... |
8f4fe51f2c92e0bc31f3d83583a5f46f | 102 156 | 4.14 Streaming and streaming protocols | |
8f4fe51f2c92e0bc31f3d83583a5f46f | 102 156 | 4.14.1 Real Time Streaming Protocol (RTSP) | The Real Time Streaming Protocol (RTSP) is an application-level protocol for control over the delivery of data with real-time properties. RTSP provides an extensible framework for controlled, on-demand delivery of real-time data, which can be both live data feeds and stored clips. RTSP is intended to control multiple d... |
8f4fe51f2c92e0bc31f3d83583a5f46f | 102 156 | 4.14.2 The Real-time Transport Protocol (RTP) | IETF RFC 1889 [11] specifies the Real-time Transport Protocol (RTP), which provides end-to-end delivery services for data with real-time characteristics, such as interactive audio and video. Those services include payload type identification, sequence numbering, time-stamping and delivery monitoring. Applications typic... |
8f4fe51f2c92e0bc31f3d83583a5f46f | 102 156 | 5 Applications and use cases | |
8f4fe51f2c92e0bc31f3d83583a5f46f | 102 156 | 5.1 Introduction | Multicast applications such as caching, streaming, and reliable transfer are not specific to satellite - but there may be satellite specific design considerations such as placement of caches (and other multicast agents), the effect of delay, the effect of subnetwork outages, and potential interactions with bandwidth-on... |
8f4fe51f2c92e0bc31f3d83583a5f46f | 102 156 | 5.2 Multicast Backbone (MBone) | The Multicast Backbone, MBone was created in 1992 as an interconnected set of subnetworks with routers capable of forwarding multicast packets for experimenting with multicasting. The MBone consists of servers equipped to handle the multicast protocol. An MBone router that is sending a packet to another MBone router th... |
8f4fe51f2c92e0bc31f3d83583a5f46f | 102 156 | 5.3 Use scenarios | |
8f4fe51f2c92e0bc31f3d83583a5f46f | 102 156 | 5.3.1 Framework | Multicast over satellite is not limited to broadband Ka/Ku - band satellite systems. Multicast services can also be delivered over L/S/C bands, as well as V/Q band in the future. However, multicast solutions favour the always-connected type of systems. Only a portion of all broadband Internet connections could be via s... |
8f4fe51f2c92e0bc31f3d83583a5f46f | 102 156 | 5.3.2 Open and closed groups | The following use scenarios are considered: • Open multicast group that can be joined from any Internet connected terminal, including satellite connections. - Caching of multicast content may be done at the gateways or at the terminals. • Closed multicast groups that are limited to the satellite network in question. - ... |
8f4fe51f2c92e0bc31f3d83583a5f46f | 102 156 | 5.3.3 Categories | Two main categories for broadband services have been specified from the network perspective: interactive services and distribution services. The interactive services are subdivided into three classes of services: • Conversational services: Typical examples are video telephony, video-conferences, video/audio information... |
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